Sensors

Chemical sensors based on metal oxides have been widely explored and used in the literature and have found different application fields as a function of their operating characteristics like selectivity, sensitivity, stability over time etc. Recently, some papers started to diffuse the idea that innovative chemical sensors could be obtained using two different metal oxides combined together providing enhanced sensing capabilities. In this paper the authors propose a new sensor based on perovskite support modified by a TiO2 based compound in order to test enhanced sensing performance. Moreover, the present work aims to show that nanocomposites obtained introducing in a matrix of a given metal oxide a second nano-structured metal oxide, which can act either as a catalyst or as a structure modifier, can provide improved sensitivity, selectivity and stability.

In this work, we investigate the effect of humidity variations on the sensing performance of Pd-graphene (GR) based devices. Palladium nanoparticles are directly synthetized onto GR sheets by microwave irradiation; the optimal palladium coverage results into a sensitive and fast hydrogen device. The dynamic conductance changes exposed to different hydrogen concentrations from 2.5 to 0.2% are displayed at room temperature, using humidified air as carrier gas at different Relative Humidity (RH) levels. The results show how the sensing curves in low humidity conditions have higher sensitivity with respect to humid environment. On the other hand, dry conditions negatively affect the sensing layer stability over time while humid conditions preserve the material.

The present contribution illustrates the early stage activities of the project CONVERGENCE FLAG-ERA H2020. The project is aimed at improving the quality of healthcare during active life by preventing the development of diseases through earlier diagnosis of cardiovascular and/or neurodegenerative diseases, and meets the growing desire of consumers for a deeper awareness of their conditions; indeed, the extensive availability of smartphones and tablets and the technology therein incorporated enable the monitoring and transmission of vital parameters from the body of a patient to medical professionals. CONVERGENCE extends this concept, aiming to create a wireless and multifunctional wearable system, able to monitor, in addition to key parameters related to the individual physical condition (activity, core body temperature, electrolytes and biomarkers), even the chemical composition of the ambient air (NOx, COx, particles). Herein is summarized the project activity, which involves ENEA group together with CEA (Commissariat à l’Energie Atomique, France) and UCL (Université catholique de Louvain, Belgium).

In this study, ternary ɣ-Fe2O3/Al-ZnO nanocomposites (NC) ware prepared using the solvothermal sol-gel process and a successive supercritical drying in ethanol. SEM analysis of the ternary NC samples showed clearly that they are formed by very small nanoparticles in the nanometer range. XRD highlighted the presence of the characteristic diffraction peaks of ɣ-Fe2O3 and ZnO phases in all samples. Conductometric sensors were fabricated and tested for the monitoring of acetone in air. Results obtained have demonstrated that the ternary composite-based sensors display higher response to acetone and ethanol compared to that obtained with Al-ZnO and ɣ-Fe2O3 ones.

Water nanocolloids of molybdenum oxide were synthesized by using a laser writing of a solid molybdenum target by a focused picosecond pulsed laser beam. The molybdenum oxide nanoparticles are then used to fabricate modified screen-printed carbon paste electrode. Morphology and compositional-structural properties of the samples were investigated by Scanning Transmission Electron Microscopy and X-ray diffraction spectroscopy. The sensors tested show enhanced electro-catalytic behavior for dopamine detection (also in presence of KCl, NaCl, glucose, uric acid, ascorbic acid and folic acid), in phosphate buffered saline (pH = 7). Under the optimal conditions, the peak current of dopamine increases linearly with the concentration in the 10–500 μM range, with the lowest detection limit of 43 nM. All these data indicate an excellent selectivity of this type of sensor towards main interferents, made it as a potential candidate for the detection of dopamine in pharmaceutical and clinical preparations.

The properties of ZnO, In2O3, and SnO2 have been investigated as possible sensing layer in resistive sensors for monitoring hexanal in food applications. Sensors performances were tested at different temperatures (100–350 °C) and analyte concentrations (50–100 ppm). Results showed the ability of the analyzed metal oxides sensors, each one characterized by its own features and operating conditions, to detect hexanal. Moreover, the different oxides response has been also related to their Gibbs free energy of formation. According to preliminary results both indium and zinc oxides show promising sensing characteristics compared to tin oxide.

This paperD., Caputo reports the development of a miniaturized lab-on-glass,suitable for the on-chip detection of living cell bioluminescenceN., Lovecchio and their on-chip thermal treatments. The glass substrate hosts, on one side, hydrogenated amorphousM., Nardecchia silicon diodes, working as both temperature sensors and photosensors, and, on the other side, transparentL., Cevenini thin films acting as heatingE., Michelini sources. The main challenge of the work is the determination of the correct fabrication recipes in orderM., Mirasoli to satisfy the compatibility of different microelectronic steps. The measured uniformity of temperature distribution, sensitivity of the temperature sensors, reverse darkA., Roda current and spectral response of the photosensors demonstrate the successful technological integration andA., Buzzin the suitability ofF., Costantini the developedA., Nascetti lab-on-glass to control theG., de Cesare cell temperature and detect the BL emission with high sensitivity.

We carried out a preliminary study, using a Direct Catalytic Methanol (or Ethanol) Fuel Cell (DMFC) in association with yeast cells (Saccharomices Cerevisiae), both to evaluate the possibility of analytically determining glucose solutions of unknown concentration, and to determine the power (in μW) obtainable from a solution with a fixed glucose concentration. In this first research, after having experimentally verified the actual functioning of the system, we optimized the operating conditions, working at room temperature, such as the current intensity as a function of the yeast concentration in solution and the contact time between cells and glucose, carrying out the measurement in potentiostatic mode. It was therefore possible both to identify a short linearity range of the method for analytical applications and to evaluate the performance of this system from an energy perspective, using the experimental power curve. We lastly have also tried to obtain a short calibration curve, to be used for analytical purposes. Finally we also measured the current intensity obtainable using a weighed amount of glucose as fuel and estimated the power achieved from the system.

In this paper the unconventional measurement technique, ‘resistance controlled mode’, which consists in driving the sensor heater in order to maintain constant the sensing-film resistance, and reading as a sensor output the temperature of the film, is applied to the detection of NO2 gas with YCoO3 based resistive gas sensors. The technique is discussed and its results are compared to those obtained with conventional measurements of resistance at constant temperature, showing that it has similar performance in terms of resolution and better in terms of speed.

Monitoring and control of vegetable ripeness is a necessary and challenging issue in the food industry; in fact, the state of ripeness during harvest, storage, and market distribution defines the quality of the final product which is approved by customer preferences. Conventional methods used to determine the shelf life of vegetable are based on chemical, microbiological, physical and sensory indices. The majority of the classical methods are time-consuming and require skilled personnel. The aim of this work was to demonstrate that a methodology based on ZnO-peptide based QCMs array of gas sensors are useful to predict the shelf life of carrots. Samples of blanched carrots were stored at different temperatures (4, 25 °C and −18 ℃) and analyzed after one month in gas-chromatography and with the sensor array. The results, analysed using principal component analysis (PCA) indicated that the sensors are able to clearly discriminate the different temperatures of storage.

The monitoring of pollutants such as sulfide anion species S2− and HS− is receiving a growing interest since they can cause acute and chronic toxicity including neurological effects and at high concentrations, even death. This study describes a new approach for optical detection of sulfide species in water samples. The method uses a silicon microchip with reagent-on-board and an integrated silicon photomultiplier (SiPM) device. The sulfide species are detected by the fluorescence signal emitted upon the reaction with N,N-dimethyl-phenylenediamine sulfate in the presence of iron(3+), leading to the formation of the fluorescent methylene blue (MB) species. A comparison with conventional fluorimetric detection method has been also carried out. Data show a very good linear correlation, proving the effectiveness of the method.

Self-assembly structured Sm2O3 nanomaterials were prepared by a simple and cost effective hydrothermal method and subsequent annealing at 800 °C in air. The size, shape and phase composition of the structures synthesized by changing the hydrothermal processing time were characterized by SEM-EDX, XRD, micro-Raman and photoluminescence (PL) analysis. Differences in particle aggregation and coalescence were reported upon varying the timing of hydrothermal process (from 24 to 36 h). Sensors performances of the synthesized Sm2O3 nanostructures have been investigated for the monitoring of two important volatile organic compounds (VOCs) such as ethanol and acetone.

This work presents the results of the crowdfunding campaign devised for MONICA, an air quality monitoring portable device. The initiative is strongly focused on the increased awareness and involvement of citizens in the air pollution issue solution. Specifically, MONICA is an architecture composed by a portable device based on an array of commercial electrochemical sensors calibrated in lab, an Android App for smartphone, a web portal (MENA) and a NOSQL backend. This infrastructure is able to manage data communication/storage and map visualization of personal exposure to air pollutants. Two associated calibration procedures are depicted, one based on in-lab recordings while the second, based on the emerging on field calibration paradigm, will refine the performance of the node. The successful, both in financial and participatory terms, campaign has reached a crowdfunded contribution of 8000 € (145% of expected 6000 €) by 102 supporters. Among them, 44 users, have opted to become part of a small fleet of human-sensors able to produce air quality data during their daily mobility routine.

A novel electrochemical device based on Nickel oxide sensing species is described. The miniaturized device contains three integrated metal microelectrodes with the working active electrode made of Ni zero-valence. It has been proved to be sensitive and versatile in the detection of glucose on saliva. The findings here reported pay the way to future development of versatile portable sensors addressing easy-to-use and low-cost system.

In this work, we propose an electrochemical DNA-based sensor for sensitive detection of organophosphorus pesticides. To improve the sensitivity of the DNA-based sensor, polyaniline film and gold nanoparticles were progressively electrodeposited on the graphite screen-printed electrode surface by cyclic voltammetry. Gold nanoparticles were then employed as platform for the immobilization of thiol-tethered DNA oligonucleotide sequence complementary to the selected biotinylated DNA aptamer for profenofos detection. Streptavidin-alkaline phosphatase enzyme conjugate was then added to trace the affinity reaction through the hydrolysis of 1-naphthyl phosphate to 1-naphthol, which was then detected by differential pulse voltammetry. A decrease of the signal was obtained when the pesticide concentration was increased, making the sensor work as signal off sensor.

The miniaturization of Real Time PCR (qPCR) systems is a crucial point towards the development of “genetic point-of-care” (PoC) that are able to offer sample-in-answer-out diagnostic analysis. Centralized laboratories and specialized staffs are needed for conventional DNA analysis. To solve this issue, we propose an innovative easy-to-use PoC technology based on a Lab-on-Disk miniaturized system, integrating nucleic acids extraction process based on Mags-Beads technology and detection based on qPCR. Lab-on-Disk system is composed by a polycarbonate disk with reagent-on-board for DNA extraction and a qPCR silicon-chip. A customized reader integrating electronic and optical modules was developed for driving the polycarbonate disk. Here we present results in the detection of Hepatitis B Virus (HBV) genome.

In the present work,Giulia, Tomagra we report on theAlfio, Battiato fabrication of a diamond-basedEttore, Bernardi device targeted to theAlberto, Pasquarelli detection of quantal neurotransmitter release. We haveEmilio, Carbone developed Multi-electrode ArraysPaolo, Olivero with 16 independent graphitic channelsValentina, Carabelli fabricated by means of Deep Ion Beam Lithography (DIBL). These devices are capable of detectingFederico, Picollo the in vitro exocytotic event from neurosecretory cells, while overcoming several critical limitations of standard amperometric techniques.

Quantification of glucose is critical in healthcare applications. Herein, in order to take advantage of both catalytic activity of NiO for glucose oxidation and high conductivity of CNTs, NiO films with different thicknesses were deposited on the surface of stacked-cup carbon nano tube (SCCNT) using atomic layer deposition (ALD) technique. Using the NiO/SCCNT composites, we demonstrated the fabrication of an electrochemical sensor with high sensitivity of 1252.3 μA cm−2 mM−1 and an ultrafast response (<2 s) for glucose determination in alkaline solution (0.1 M KOH). Additionally, exploiting ALD technique provided us with an opportunity to deposit NiO on the SCCNT surface with different thicknesses, which in turn, enabled us to evaluate thoroughly the effect of different thicknesses of NiO on glucose measurement.

The miniaturization of integrated nucleic acid testing devices represents a critical step toward the development of portable systems able to offer sample-in-answer-out diagnostic analysis. The conventional molecular testing workflow involves laboratory infrastructures and well-trained staff. Here we present a versatile, user-friendly miniaturized Lab-on-Chip device for the molecular diagnostics of infectious diseases. It is composed of a polycarbonate ring and a silicon chip; a customized reader integrating electronic and optical modules was developed for driving the thermal and optical processes. We report the results obtained using our device for the sample processing and detection of gram-negative opportunistic pathogenic bacteria.

New recognition probes sensible, specific and robust is one of the major problems of biosensor assay. Detection biosensors has utilized antibodies or enzymes as bioreceptors; however, these have numerous disadvantages of limited binding sites and physico-chemical instabilities, can negatively affect capture and detection of target in diagnostic device. In this contest, Phage-Display provides a valuable technique for obtaining large amounts of specific and robustness bio-probes in a relatively short time. This technique relies on the ability of M13 bacteriophages (or phages) to display specific and selective target-binding peptides on major coat protein pVIII of their surface. In this work, we used P9b phage clone, displaying a foreign peptide QRKLAAKLT to selectively recognize Pseudomonas aeruginosa like bioreceptor. We describe different methods of functionalization to realize a selective bacteria biosensor surfaces. Several surfaces, such as latex and magnetic beads and polymeric surfaces such as mica, APTES and PEI, were functionalized by covalent bonds or physisorption with P9b. The efficiency of the surface functionalization procedures was evaluated by ELISA and AFM, while capture efficiency of the anchored phages has been assessed by plate count and Fluorescence microscopy. The results of this work pave the way to the use of phages as bioreceptor.

Optical biosensors are powerful alternatives to the conventional analytical techniques, due to their particular high specificity, sensitivity, small size, and cost effectiveness. Although promising developments of optical biosensors are reported, new bioprobes of cheap and easy synthesis are required, for detection of eukaryotic cells or dangerous infectious agents. In this regard, silicon nanoparticles (SiNPs) can be used as nanoplatform owing to their high specific surface area, optical properties and biocompatibility. They can also be functionalized with bio-probes and used in diagnostic applications. Different methods are described to obtain a stable bond between SiNPs and probes such as nucleotides, antibodies or peptides; however, the latter show many disadvantages about folding instability and sensitivity during the functionalization. Phage Display is a technique for the screening and selection of peptide ligands, that uses an engineered filamentous bacteriophage, mostly made up of 2700 copies of a major coat protein (pVIII) displaying a foreign peptide specific for a target. The bacteriophage or its coat proteins alone can be used as probes to functionalize nanomaterials such as SiNPs. In this work, we propose a new approach to obtain fluorescent bio-probes that can be used for the realization of an optical biosensor. By pulsed laser ablation in liquid (PLAL), SiNPs are functionalized in a “one step” process with phages or isolated pVIII-engineered proteins, selective for Pseudomonas aeruginosa. This process led to complexation of SiNPs with both bioprobes proposed. The PLAL did not alter the biological function of phage probes, maintaining their binding capacity to the bacterial target.

Discovery of new markers for the identification and discrimination of cell types is one of the principal objectives in cancer diagnostics. In the last years, many researchers used phage-display technology in vitro and in vivo to obtain random peptide probes able to bind towards cancer targets to be used in diagnostic systems and new targeted drug. In this work, we proposed a Single Drop Biosensor based on phage-labelled probes to detect leukaemia cells in blood from patients affected by chronic lymphocytic leukaemia (CLL). Results show that phage-labelled probes were able to recognize lymphocytes and lymphoblastic cells both in leukemic peripheral blood mononuclear cells and in whole blood from patients affected by CLL. The “proof of concept” proposed, using the phage labelled as bio-probe, could be an alternative way to produce new biosensor for monitoring of chronic pathology. Furthermore the results may have translational relevance for identification and exploring of new ligands directed against cancer hematological cells.

This work is focused on optimizing adhesion and distribution of colloidal gold nanoparticles on silanized glass substrates intended as nanostructured plasmonic transducer for sensing applications. This system will be used as platform for subsequent functionalization and/or enzyme immobilization. All preparation steps have been monitored by UV-Vis absorption spectroscopy and X-ray photoelectron spectroscopy (XPS).

The small intestine is the central component of the gastrointestinal (GI) tract (gut) where nutrients are absorbed into the body. Its functional structure is mainly based on its extremely extended surface area, further increased by a specific carpet of villi, responsible for the translocation of nutrients from the GI lumen into the bloodstream. Also, in the small intestine, the absorption processes of the orally administered drugs are basically related to the pharmacokinetics [1]. The deficit of cell culture methods to maintain in vivo–like functions forces researchers to optimize and apply methods in which cells are seeded and cultured under controlled and dynamic fluid flow [2]. Moreover, the lack of predictive human organ models has increased the necessity of approaches for proper mimicking of organ function in vitro, studying physiological parameters that regard mechanical, chemical and physical stimuli crucial for differentiation, morphology and function of the epithelia [3]. In this work we present a Gut-On-Chip (GOC) device, equipped with ITO (Indium tin Oxide) electrodes patterned by wet etching techniques, as a multifunctional microsystem for monitoring epithelial parameters. The potential to support cells adhesion, growth and polarization of a functional monolayer is also investigated in the Caco-2 epithelial-like cell line by in-device seeding and culture. In a perspective, this first prototype has established the basis for several technology integrations to study complex cellular phenomena targeted in key physiological topics (e.g. the tight interplay of different physical effects during mechanotransduction processes) and in pharmacological open issues such as drug absorption and metabolism.

This workF., Costantini presents a portable lab-on-chip system, basedR. M., Tiggelaar on thin film electronic devicesR., Salvio and an all-glass microfluidic network, forM., Nardecchia the real-time monitoring of enzymatic chemiluminescent reactions. The microfluidic networkS., Schlautmann is patterned, through wet etching, in a 1.1 mm-thick glass substrate that is subsequently bonded to a 0.5 mm-thick glass substrate. The electronic devices are amorphousC., Manetti silicon p-i-n photosensors, deposited on the outer side of the thinner glass substrate. The photosensorsH. J. G. E., Gardeniers, the microfluidic network and the electronic boards reading out the photodiodes’ currentD., Caputo are enclosed in a small metallic box ( $$10 \times 8 \times 15\,\mathrm{cm}^3$$ ) in order to ensure shielding from electromagnetic interferences. Preliminary tests haveA., Nascetti been performed immobilizing horseradish peroxidase on the inner wall of the microchannel as model enzyme for detecting hydrogen peroxide. Limits of detection and quantificationG., de Cesare equal to 18 and 60 $$\upmu $$ M, respectively, have been found. These values are comparable to the best performances reported in literature for chemiluminescent-based optofluidic sensors.

A novel paper-based biosensors for the measurement of urinary phenylalanine (Phe) was developed and the experimental results here reported. The proposed biosensor is featured by a silicon part integrating temperature sensors and heaters and a polycarbonate ring to form a microchamber. The reagent-on-board format allows a fast and easy self-testing directly from patients. The biosensors is thermally driven by a customized instrument and software. The detection strategy employed is based on the specific reaction of Phenylalanine Ammonia Lyase enzyme to produce ammonia and trans-cinnamic acid from Phenylalanine. The increase of pH value is proportional to the Phe amount and can be monitored by the color changes of a dye solution. The proposed system is suitable to detect the phenylalanine levels in a linear dynamic range concentration from 20 to 3000 μM.

In this paper, we present the magnetoencephalography system developed by the Institute of Applied Sciences and Intelligent Systems of the National Research Council and recently installed in a clinical environment. The system employ ultra high sensitive magnetic sensors based on superconducting quantum interference devices (SQUIDs). SQUID sensors have been realized using a standard trilayer technology that ensures good performances over time and a good signal-to-noise ratio, even at low frequencies. They exhibit a spectral density of magnetic field noise as low as 2 fT/Hz1/2. Our system consists of 163 fully-integrated SQUID magnetometers, 154 channels and 9 references, and all of the operations are performed inside a magnetically-shielded room having a shielding factor of 56 dB at 1 Hz. Preliminary measurement have demonstrated the effectiveness of the MEG system to perform useful measurements for clinical and neuroscience investigations. Such a magnetoencephalography is the first system working in a clinical environment in Italy.

In recent years, the multi acoustic sensors systems have had a major development thanks to their versatility in different fields. These systems, also called acoustic antennas, consist of a set of microphones distributed according to linear, planar or three-dimensional geometries. The acoustic signals detected by the microphones are processed in order to define the location of an acoustic source. The acoustic antennas find large applications in different fields. In automotive they are used to highlight the noise propagation path; in the multimedia, these sensors allow localizing a speaker without portable microphones. Also the civil safety and military fields benefit from these systems: gunshots detection in city areas, fire prevention in wooded zones (Blaabjerg et al. in IV International Conference on Forest Fire Research, 2010), soldiers protection from enemy attacks are just some possible applications (ShotSpotter Gunshot Location System® (GLS). http://www.shotspotter.com ). Even in the aerospace field, there are interesting applications such as the monitoring of the air traffic zones (ATZ), locating a plane and tracing its trajectory (Quaranta et al. in ESAV 2011-Tyrrhenian International Workshop on Digital Communications-Enhanced Surveillance of Aircraft and Vehicles, 2011 and Petrella et al. in ICSV19, 2012). The identification of the position of the source requires the knowledge of right acoustic locations of the microphones in the array, generally different from the geometric locations, to this scope a suitable calibration procedure. The proposed method was tuned in a simulation environment to predict signal produced by each microphone. An optimization process was adopted to identify layout configuration guaranteeing the right calibration. The proposed solution was experimentally validated on a two-dimensional acoustic antenna.

Nowadays, cell characterization represents a fundamental task widely diffused in different fields. The main purpose of this paper is the design and development of a device for cellular characterization based on a pyroelectric sensor. After a brief introduction dedicated to the methods actually employed for cell counting, the pyroelectric sensor, the electronic readout unit, and the prototype will be introduced. Different cell concentration samples have been analyzed in order to highlight how the induced pyroelectric response is related to the cell properties. Experimental results shown that sensor output is strongly affected by cell type, concentration and viability. Particularly, it has been observed an increase in output signal related to an increase in cell concentration, mainly due to a lower thermal conductivity. No significant variation has been observed by the drastic reduction of cell viability also by varying cell concentration. The aforementioned results are probably due to the induction of a decrease in mitochondrial activity. Obtained results are very promising for the realization of a low cost laboratory device with all the characteristics listed above.

Non-destructive tests based on eddy currents (EC-NDT) are one of the inspection techniques used to detect and characterize defects in conductive structures. The EC-NDT technique is based on the induction of eddy currents in the material under test and on the analysis of the reaction magnetic field that is generated. In this way, it is possible to detect the presence of a defect and evaluate its geometric characteristics. Generally, magnetic sensors such as AMR or GMR can be used to detect the reaction magnetic field. Recently, magnetic field sensors based on the Tunnel effect (TMR) have been introduced, which seem to have better performances than previous solutions. In this context, the article illustrates the metrological characterization of a TMR sensor for EC-NDT applications, as the information provided by the manufacturer is not complete and sufficient for this type of use. The results obtained show that the TMR sensor is able to provide a higher sensitivity than the AMR and GMR sensors, with a limited measurement uncertainty. This makes it possible to assume that the TMR sensors can be usefully used in EC-NDT applications.

Polymeric composites, where polymeric matrices are purposefully added with suitable fillers, have raised the interest of the scientific community, since materials with characteristics that depend on the nature of both the polymeric matrix and the filler can be obtained. The paper deals with the investigation of composites based on an insulating polymeric matrix, realized by using polydimethylsiloxane (PDMS) and carbon black (CB), as the filler, for realizing nanocomposites. The PDMS is an insulating matter, while the CB has conducting properties. If a suitable concentration of the CB is used, it is possible, therefore, changing the electrical properties of the composite from insulating to conducting. Such a possibility is, e.g. described in the framework of the percolation theory. Since a deformation of the composite causes a corresponding change in the concentration of the filler, it is possible using the described nanocomposites as piezoresistive elements. Based on the considerations reported above, composites were realized by using different concentrations of the filler, in order to obtain a reasonable value of the composite resistivity. The corresponding thermal, mechanical and electrical properties where, therefore, investigated in typical laboratory conditions.

In this work we want to compare performances of different plasmonic sensors, obtained by different polishing processes of D-shaped Plastic optical fibers (POFs). Three D-shaped POF plasmonic sensor configurations, obtained by three different polishing processes, have been created and experimentally tested. The proposed devices are based on the excitation of surface plasmons at the interface between the under test medium and a thin gold layer directly deposited on plastic fiber core (D-shaped area). The experimental results have shown that the performances are influenced by surface roughness variations in the D-shaped POF region.

As a proof of principle, we have developed a novel surface plasmon resonance (SPR) sensor used to monitor the interaction between a molecularly imprinted polymer (MIP) and a small molecule as the substrate. This plasmonic platform is based on a removable polymethyl methacrylate (PMMA) chip with a thin gold film on the top, two PMMA plastic optical fibers (POFs) and a special holder, designed to obtain the plasmonic phenomenon. We have experimentally tested whether the optical sensitivity is sufficient for monitoring an MIP receptor. The advantage of MIPs is that they can be directly deposited on a flat gold surface by a spin coater machine, without modifying the surface, as needed for the bio-receptors. With this new sensor, it is possible to achieve remote sensing capabilities, by POFs, and also to realize an engineered platform with a removable chip sensor.

A multi-analyte biosensing platform for the selective label-free detection of protein biomarkers has been designed through a three-dimensional model based on the finite element method. The sensing element of the platform is a planar plasmonic nanocavity, consisting of a one-dimensional periodic structure (Bragg grating) in gold, with a defect, placed on the buried oxide of a silicon-on-insulator substrate. The footprint of this sensing element, which has a good chemical stability, is only 1.57 μm2. The sensor has a detection limit of 128 pg/mm2 and a surface sensitivity of 1.8 nm/nm.

In the present investigation a new intensity-based sensor platform for refractive index sensing is presented. It is based on a special holder, a slab waveguide and two Plastic optical fibers (POFs). In particular, we present a comparison between two different configurations: the slab waveguide with and without a buffer layer. Advantages of this new approach are the possibility of sensing with a removable chip, the easy production of an engineered platform and the use of a special holder, which is also suitable for thermo-stabilized flow cells implementation.

Atmospheric particulateLuca, Lombardo is one of the main responsible for the environmental pollution of highly populated cities. The particulate matter can be considered an aerosol of many particles,Marco, Parvis with different shapes, morphologies and sizes down to few micrometersEmma, Angelini. These small particlesNicola, Donato are responsible for climate changes and, when inhaled, can reach the lungs causing respiratorySabrina, Grassini and cardiovascular diseases. Usually commercial sensors are based on passive filters and are designed to measure only particles whose size is below a certain value. Therefore, a measuring system capable of assessing the quality of air and evaluating not only the amount of particles, but also the size distribution of the particulate matter in urban atmospheres could be extremely helpful. This paper describes a simple and cheap optical solution, which is able to detect the total amount of solid pollution particles and classify them according to their average size, giving a fast response to the users.

Radioactive dust mobilization is a risk that can occur in many nuclear plants and, in order to reduce the risk related to this event, it is necessary map the velocity vectors of dust during its mobilization. The authors have designed and used a chain of measurements for air pressure and velocity, temperature, and dust velocity used on the experimental facility STARDUST-Upgrade that can replicate the thermos-fluidodynamic conditions of the loss of vacuum accidents with a pressurization rate in a range of 10–1000 Pa/s and a temperature in a range of 20–140 ℃. In this work, the authors present the optical experimental setups and software used to track dust velocities. These techniques are based on the particle tracking velocimetry and flow motion algorithms. Two different experimental setups are used to take into account the different optical properties of dust, each image obtained during the experiments has been analysed with customized software. Three different of algorithms are analysed and criticaly compared in this work: Lucas-Kanade, feature matching and Horn-Schunck. The authors will evaluate the performances of these optical techniques developed and used to map the velocities vectors of radioactive dust.

Compared to traditional silicon electronics, printed sensors are cheap and suitable for many low cost and disposable devices. Main printing techniques used are screen printing and inkjet printing. In particular we focus on inkjet printing for the rapid prototyping of sensors. Inkjet is a direct, contactless, printing process, with high spatial resolution and compatibility with many substrates. Successful examples of sensors developed by low cost inkjet printers and metal-based inks are reported by authors. In this paper two examples of low cost inkjet printed sensors are given. The first device is an accelerometer aimed to address typical applications in the field of human and seismic monitoring. Main outcomes of the proposed solution are the low frequency operation and the high sensitivity. The realization of a CO2 gas sensor is also presented. The device makes use of a PEDOT/PSS and Graphene stack and exploits resistive readout.

Dip-pen lithography (DPL) technique has been employed to develop a new flexible biosensor realized on nylon with the aim to detect the activity of human topoisomerase. The sensor is constituted by an ordered array of a DNA substrate on flexible nylon supports that can be exploited as a drug screening platform for anticancer molecules. Here, we demonstrate a rapid protocol that permits to immobilize minute quantities of DNA oligonucleotides by DPL on nylon surfaces. Theoretical and experimental aspects have been investigated to successfully print DNA oligonucleotides by DPL on such a porous and irregular substrate.

The possibility to implement engineered devices to obtain feedbacks from biological samples is taking diagnostics and biotechnological research to a new level. Aerosol Jet Printing (AJP) represents a promising technique for this kind of applications. The benefits are related to manufacturing of customized, complex geometries with a high resolution even on irregular surfaces without masks. In this paper, we present the realization of an Aerosol Jet Printed microdevice addressed to protein detection and quantification in biological samples. The sensor was realized with particular attention to materials and geometry choices. The thickness of printed layers was measured thanks to a profilometer, while an electrical evaluation was performed thanks to a multimeter, in order to measure the electrical resistance offered by the printed elements. Finally, the possibility to immobilize antibodies on sensor surface for electrochemical protein quantification was assessed with fluorescence imaging. Final results obtained stated the possibility to print with AJP high resolution lines, with proper values of resistivity. Imaging findings showed a good adhesion of antibodies on the electrodes, Ag-based Anodic stripping voltammetry confirmed sensors’ capability to quantify proteins, proposing the designed sensors as promising for the analysis of real biological samples.

Nowadays the world of sensors is gaining a primary importance in the electronics field, thanks to the boom of the smartphones and IoT market. Capacitive sensors are widely involved in the most of applications, from the biomedical to the gaming industry, and they can sense a wide variety of physical quantities. In this work we focused on force sensing capacitive sensors, trying to mix two of the most in-fashion markets, sensors and polymers. Polymers industry is constantly growing and, by the constant synthesis of new bio-based molecules, it will quickly enter the most of the technology markets. We made a soft capacitive force sensor, by inserting a coplanar capacitor in a polymeric wafer structure. The involved technology is derived from the touch-sensing technique, usually involved in appliances’ user interfaces. This sensor is easy to make and cheap, and it was tested with a force of 1 N. It is waterproof and non-sensitive to moisture variation in the outer environment. It shown a sensitivity of 172 fF/N, with a resolution of 80 mN. As it is only a preliminary study, more investigations are needed in order to obtain a deeper characterization versus different environment conditions and with higher force stimuli. It will be also relevant to evaluate the behavior of the sensor by using different polymers.

In this work, the possibility of manufacturing chemiresistive volatile organic compounds sensing devices by inkjet printing an aqueous suspension of graphene-like layers on paper substrates has been studied. The electrical responses of the devices have been analyzed upon exposure to ethanol at room temperature in dry ambient and analyzed in terms of the conductance variation. Additionally, a reproducibility analysis on the device performances has been investigated.

Carbon Black Nanoparticles (CBNPs) onto Screen-Printed electrodes (SPE) are proposed as an electrode modifier for assisting electrodeposition of PB for non-enzymatic hydrogen peroxide electrochemical sensing. CBNPs allows an effective PB electrodeposition on SPE modified electrodes and enhance the electrochemical rate constant for the reduction of hydrogen peroxide (H2O2) compared to bare SPE.

Two versions of a PPG/ECG combined system have been realized and tested. In a first version a multisite system has been equipped by integrating 3 PPG optodes and 3 ECG leads, whereas in another setup a portable version has been carried out. Both versions have been realized by equipping the optical probes with SiPM detectors. SiPM technology is expected to bring relevant advantages in PPG systems and overcome the limitations of physiological information extracted by state of the art PPG, such as poor sensitivity of detectors used for backscattered light detection and motion artifacts seriously affecting the measurements repeatability and pulse waveform stability. This contribution presents the intermediate results of development in the frame of the European H2020-ECSEL Project ASTONISH (n. 692470), including SiPM based PPG optodes, and the acquisition electronic components used for simultaneous recording of both PPG/ECG signals. The accurate monitoring of dynamic changes of physiological data through a non-invasive integrated system, including hemodynamic parameters (e.g. heart rate, tissue perfusion etc.) and heart electrical activity can play an important role in a wide variety of applications (e.g. healthcare, fitness and cardiovascular disease). In this work we describe also a method to process PPG waveform according to a PPG process pipeline for pattern recognition. Some examples of PPG waveform signal analysis and the preliminary results of acquisitions obtained through the intermediate demonstrator systems have been reported.

Structural Health MonitoringFederica, Zonzini functionalities are aimed at constantly assessing the health of a building in order to preventLuca, De Marchi dramatic consequence of a damage. This work describes a well-defined wireless sensor network system installed over a steel beam capable to perform modal parameters estimation, such as naturalNicola, Testoni vibration frequencies and modal shapes. Signal Processing Techniques were aimed at computing Power Spectral Density of the acceleration signals acquired, dealing with parametric and non parametric approaches. Algorithms in frequency domain, together with the Second Order Blind Identification method were implemented for modal shapes reconstruction. Beside a satisfactory agreement between the theoretical model and the output response of the algorithms implemented, versatility, easiness of reconfiguration, scalability and compatibility with long term installation are among the most powerful advantages of the architecture proposed. Light weight, low power consumption also enhance the capabilities of the system to provide real-time information in a relatively cheap way.

Control and monitoring systems base their decisions on the information provided by transducers. These signals must be acquired, processed and transmitted. There is an exchange between sensor signal processing and data rate, more signal processing inside the transducer implies lower data rate over the networks. This paper presents the standard IEEE 21451-001 whose main purpose is to extract knowledge of transducer signals that can be shared with others to increase system reliability, infer shapes, normal/abnormal states and to provide a normalized building structure for extracting knowledge. This standard extracts information directly from sampling based on a more complete structure. The standard is described highlighting the purpose and the main algorithms.

The aim of this paper is to study the state of the art about the metrological characteristics and the accuracy of wearable devices, tested in comparison to a gold standard instrument. A bibliographic research has been made on the main scientific databases (e.g. Scopus and Web of Science). Papers have been included on the basis of established criteria (e.g. the wearable device has to be commercial). At present, neither a standard protocol nor fixed metrological characteristics can be identified in the literature. Among the most discussed wearable devices, there are certainly Fitbit, Jawbone, Garmin and Polar ones. Chest-strap monitors generally result to be more accurate than wrist-worn devices, which, on the other hand, are cheaper and more comfortable. Given the lack of standards in the validation process, the data appear to be very irregular (even among studies conducted on the same device) and consequently barely comparable. It would be extremely important to conduct a pilot study on a few devices, validating them according to an established test protocol and comparing the results to a gold reference instrument (e.g. ECG for Heart Rate assessment). In this way, it would be possible to start building a database of the accuracy and the metrological characteristics of wearable devices.

In this paper, a positioning technique based on measuring the Time Difference of Arrival (TDoA) of ultrasonic chirp pulses is proposed. The implementation issues of the proposed method are discussed and the development of two versions of low-complexity prototype is presented. Experimental results from a measurement campaign using the realized prototype are presented, demonstrating sub-centimeter position measurement accuracy in the short range, thus validating the proposed technique.

The original proposal of Advanced Metering Infrastructure based on short-range communication (wM-Bus) is suggested for the continuous monitoring of Particulate Matter within Smart Cities. A prototype of water meter equipped with a low cost off-the shelf PM sensor has been developed as remote node to be adopted in the radio Local Area network. Result of the metrological characterization against the quality requirements of the PM measurement according to European regulations as well as the simulation of a typical Smart Metering scenario in terms of communication performance confirm the feasibility of the proposed AMI for an effective adoption within urban areas.

The first step of this research has been to discriminate, by means of a commercial electronic nose (e-nose), the maturity evolution of seven types of fruits stored in refrigerated cells, from the post-harvest period till the beginning of the marcescence. The final aim was to determine a procedure to select a reduced set of sensors that can be efficiently used to monitor the same class of fruits by a low cost system with few, suitable sensors without loss in accuracy and generalization. To define the best subset we have compared the use of a projection technique (the Principal Component Analysis, PCA) with the sequential feature selection technique (Sequential Forward Selection, SFS) and the Genetic Algorithm (GA) technique by using classification schemes like Linear Discriminant Analysis (LDA) and k-Nearest Neighbor (kNN) and applying two data pre-processing methods. We have determined a subset of only three sensors which gives a classification accuracy near 100%. This procedure can be generalized to other experimental situations to select a minimal and optimal set of sensors to be used in consumer applications for the design of ad hoc sensory systems.

This work presents a multi-sensor platform integrating one or more commercial low-cost ambient sensors and one wearable device for the automatic assessment of the physical activity and sedentary time of an aged person. Each sensor node could operate in a stand-alone way or in a multi-sensor approach; in the last case, fuzzy logic data fusion techniques are implemented in a gateway in order to improve the robustness of the estimation of a physiological measure characterizing the level of physical activity and specific parameters for the quantification of a sedentary lifestyle. The automatic assessment was conducted through two main algorithmic steps: (1) recognition of well-defined set of human activities, detected by ambient and wearable sensor nodes, and (2) estimation of a physiological measure, that is (MET)-minutes. The overall accuracy for activity recognition, obtained using simultaneously ambient and wearable sensors data, is about 5% higher of single sub-system and about 2% higher of that obtained with more than one ambient sensor. The effectiveness of the platform is demonstrated by the relative error between IPAQ-SF score (used as ground-truth, in which a low score corresponds to a sedentary lifestyle whereas a high score refers to moderate-to-vigorous activity level) and average measured (MET)-minutes obtained by both sensor technologies (after data fusion step), which never exceeds 7%, thus confirming the advantage of data fusion procedure for different aged people used for validation.

This paper focuses on failure modes and mechanisms of the main sensors used in Oil&Gas field, especially for Safety application, in the Safety Instrumented System design. Moreover, the role of the on-board diagnostic will be also discuss and how it improves the capability to detect a failure mode in the sensors used in safety critical applications.

Colorectal cancer (CRC) is one of the most common cancers worldwide. In the United States is currently the third deadliest cancer with more than 1 million patients diagnosed annually of which 50% will develop metastatic disease. In some subtypes of CRC, the KRAS mutation status has emerged as an important diagnostic/prognostic marker for the response to treatment with anti-EGFR drugs in patients with metastatic CRC. Currently, the direct sequencing remains the gold standard technique for the diagnosis of DNA mutations, but the low sensitivity, time-consuming and the need for operating in rooms with dedicated instrumentation makes this method disadvantageous in daily practice. In recent years, new technologies characterized by different sensitivities, specificities and complexities are starting to be used in research and clinical studies for the detection of DNA genotyping. In this work, we propose a novel portable Lab-on-Disk platform developed by STMicroelectronics as a competitive device able to perform TaqMan-based real-time PCR for the rapid and simultaneous detection and identification of KRAS gene mutations.

As bacterial infection diseases represent a relevant threat for human health worldwide, many efforts are spent in accelerating the diagnostic process of biological specimens. The WASPLab automated platform, by COPAN Italia S.p.A., detects bacterial growth by processing the images of the Petri dishes containing a sample to analyze. This work presents a study performed on a developed system that exploits impedance measurement to monitor bacterial growth in Petri dishes in real time. It is part of an activity aiming at system integration in the WASPLab, to enhance its monitoring capabilities and flexibility. Through repeated 24-h tests executed with the system, we successfully detected S. aureus growth in Petri dishes that were inside one of the WASPLab incubators, starting from impedance measurements performed at 50–150 Hz. In particular, depending on the parameter being observed, detection time was between four and six hours, for an initial bacterial concentration in the order of 4.5 · 107 CFU/ml. These preliminary results represent the first step for evaluating system integration in the WASPLab.

In the context of automotive and two-wheeled vehicles, the comfort and safety of drivers and passengers is even more entrusted to electronic systems which are closed-loop systems generally implementing suitable control strategies on the basis of measurements provided by a set of sensors. Therefore, the development of proper instrument fault detection schemes able to identify faults occurring on the sensors involved in the closed-loop are crucial for warranting the effectiveness and the reliability of such strategies. In this framework, the paper describes a virtual sensor based on a Nonlinear Auto-Regressive with eXogenous inputs (NARX) artificial neural network for instrument fault diagnosis of the linear potentiometer sensor employed in motorcycle semi-active suspension systems. The use of such a model has been suggested by the particular ability of NARX in effectively take into account for the system nonlinearities. The proposed soft sensor has been designed, trained and tuned on the basis of real samples acquired on the field in different operating conditions of a real motorcycle. The achieved results, show that the proposed diagnostic scheme is characterized by very interesting features in terms of promptness and sensitivity in detecting also “small faults”.

In this work we developed a Smart Breath Analyzer device devoted to the tele-monitoring of exhaled air in patients suffering Chronic Obstructive Pulmonary disease (COPD) and home-assisted by mechanical ventilation. The device based on sensors allows remote monitoring of a patient during a ventilotherapy session, and transmit the monitored signals to health service unit by TCP/IP communication through a cloud remote platform. The aim is to check continuously the effectiveness of therapy and/or any state of exacerbation of the disease requiring healthcare. By preliminary experimental tests, the prototype was validated on a volunteer subject.

In this contribution, an innovative platform for ECG assessment from PPG signals for automotive applications is presented. The platform we propose is based on an optical miniaturized probe coupling a LED emitter with a silicon photomultipliers (SiPM) detector. The optical probe is able to measure PPG signal from the palm of hands. The new nonlinear Pattern Recognition Pipeline we developed associate the “Diastolic phase” of the heart to a “Reaction” physical dynamic while the “Systolic phase” can be mathematically modelled having a “Diffusion” physical proprieties. Results show there is specific cross-correlation between ECG signal and first-derivative of processed PPG waveform for the same person.

In this work, we present an innovative sensing and monitoring system of indoor environment parameters and structural elements of a building. The system has been conceived and optimized for modern wooden structures; it is organized with a control unit and sensing nodes that can be arranged freely. This architecture allows to provide continuous information about inside and outside ambient temperatures, moisture conditions and tri-axis inclination of structural elements. The data, continuously monitored, are collected on a web server able to check the overall status of the building and to generate automatic warnings and alerts for any criticisms. A web-application has been also developed for system monitoring, giving the possibility to create summary report and to analyse the data profiles. The system is currently working on a novel public construction fabricated in XLAM and designated for school activities in Lucca (Italy). All measurement results will be shown in the full paper.

A temperature control loop for capacitive humidity sensors has been developed in 0.35 µm CMOS technology and characterized with experimental lab measurements. The proposed circuit is employed for self-diagnostics of the humidity sensor as well as for auto-calibration, thanks to correlation between relative humidity and temperature. An input Switched-Capacitor (SC) thermometer read-out circuit compares the measured temperature value with a setpoint while a SC PWM PI circuit drives a power n-MOS to deliver heat to the sensor. Measurements results summary is reported. The temperature loop accuracy is ±0.25 ℃ in a range from room temperature to 50 ℃, while consuming 0.9 mA from a single 3.3 V supply for the control and about 43 mW for delivering heating power.

Air quality is a source of increasing concern in several cities, due to the adverse health effects of significant pollution levels. For this reason, the need to assess the concentration of pollutants at high temporal and spatial resolution is perceived as very urgent. As such, there is a growing interest in building pervasive networks integrating different sensing technologies to achieve this capability. In this view, low cost smart sensors data could be fused together with fixed but more accurate multisensor devices and certified analyzers data to build hi-res maps (<100 m) of pollutant concentrations. Low cost UAVs are versatile platforms capable to host playloads integrating multi sensor technologies for short term, mobile monitoring tasks. The recently proposed tethered UAV platforms can be deemed as interesting solutions to build and rapidly deploy impromptu networks of air quality analyzers for mid-term environmental monitoring actions. In this work, we propose the integration of the ENEA MONICA multisensor platform as a measurement payload for the TopView SAV-ES UAV. The prototype has been flow on board of the SAV-ES platform for test flight targeting the measurement of a plume generated with a brushwood controlled fire. The functional proof of concept flight have confirmed the possibility to use MONICA as a measurement payload for the targeted platform.

It has been observed that patients with some neurodegenerative diseases (such as Alzheimer, Parkinson etc.) accumulate metals in their nervous system, in particular the area of interest is the basal ganglia region. Several solutions can be considered such as Magnetic Resonance Imaging (MRI), Positron Emission Tomography (PET), and SQUID magnetometers. It should be noted that the first approach works without radioactive tracers, however in presence of patients with implanted devices the MRI cannot be used. The PET is an invasive technique which requires use of radioactive tracers and the SQUID is a solution that can be pursued but it is expensive and it is a sophisticated method of measurement with a complex set-up and it is an expensive cryogenic instrumentation. In this paper, the possibility to use the Flexible RTD-Fluxgate magnetometer as alternative low cost solution, able to detect weak magnetic fields or field perturbations with low dimensions, high sensitivity, low power consumption and an intrinsic digital form of the output signal as respect the classical second harmonic fluxgate, will be addressed. Experimental results are shown that encourage to pursue this approach in order to obtain simple devices that can measure several quantities of known ferromagnetic compounds accumulated in a localized area in order to be used as diagnosis method.

Among the olderSusanna, Spinsante adults population, falls represent a serious health problem, and a considerable economic issue for the society as a whole, due to their many consequencesMatteo, Pepa. In order to design reliable systems for automatic fall detection, ableStefano, Pirani to distinguish falls from activitiesEnnio, Gambi of daily living, the sensor fusion approach may be exploited. In this paper, the quite innovative fusion of Micro Doppler Radar and Kinect sensors to achieve acceptable accuracy and sensitivity in fall detection is investigatedFrancesco, Fioranelli. The results show that by fusion, it is possible to provide a 100% fall detection sensitivity, over a dataset collected by taking into account ten different actions, with proper configuration of the acquisition setup and algorithmic parameters.

Infertility is one of principal health and social problems of this century. Male factors are involved in half of the cases and often the alteration concerns sperm motility. Seminogram is the gold standard technique for semen analysis, but it presents several limits. For this reason, we propose a new method for discriminating asthenozoospermic samples (low sperm motility) from normozoospermic ones (progressive motility > 32%) based on the never explored analysis of the volatile metabolites in the headspace of human semen sample by Gas Chromatograph (GC) equipped with two detectors: a Mass Spectrometer (MS) and a metal oxide based gas sensor sensitive (MOX) to Volatile Organic Compounds (VOCs). VOC sensor signal profiles (resistance vs. time) showed a higher sensitivity to specific organic classes such as aldehydes and ketones. The sensorgrams were preprocessed and analysed by PLS-DA. The results showed that sensorgrams analysis by suitable bioinformatics techniques has a good discrimination power and could support physiological parameters in human semen assessment. The analysis of the human semen Volatilome may be a proof-of-concept for the development of a novel micro-GC device with a sensor array detector, a potential candidate for infertility assessment in clinical practice.

As the technology is advancing, biotechnologist and pharmacologist seems more interested and focused towards the development of innovative sensing solution/technology capable of evaluating proteins without any limitations of time and cost which were encountered/offered by conventional/traditional methods such as ELISA used for protein quantification. To allow continuous monitoring and attain protein sample information in a non-invasive way, spectrophotometry might be considered as an alternate method which analyzes different conformational states of proteins by closely observing the variation in optical properties of the sample. The work presented studies p53 protein conformational dynamics and their involvement in various pathophysiological and neurodegenerative disease/disorders using the spectrophotometer-based method. By utilizing the technique of spectrophotometry, investigations were carried out on three samples containing varied molecular state of p53 (Wild p53, Denatured p53, and Oxidized p53), to detect the difference in light absorption. Overall, this proposes the possibility of a simple, non-invasive and optical based method capable of detecting and identifying different structural states of p53 while overcoming the complexities offered by the conventional procedures.

In recent years, energy harvesting studies have grown significantly. Energy recovery for low power applications is assuming considerable importance for powering non-essential auxiliary circuits. Among the various sources of energy that can be found in nature, in this paper we consider the Plant-Microbial Fuel Cell (P-MFC), fed by bacteria present in the roots of plants. We show a preliminary study for the optimization of P-MFC energy harvesting. The system considered is a collection of series and parallel connected pot plants. The main principle of operation is the one of a microbial cell. Plants through photosynthesis produce sugars that are subsequently released into the soil through the roots. Bacteria present near the roots consume these sugars and produce ions. Therefore, thanks to an redox process, by introducing two electrodes into the ground (anode and cathode) it is possible to obtain a potential difference that can be exploited as an energy source for indefinitely feeding electronic devices, even where it is not possible to have a direct connection to an outlet.

Devices that track the human body movement are heavily used in numerous and various fields like medicine, automation and entertainment. The work proposed is focused on the design of a modular device able track the flection of human hand phalanxes. The overall system composed by two parts: a computer program interface and a modular wearable system applied to the finger whose motion is to be monitored. The wearable device is equipped with an Inertial Motion Unit (IMU) with the purpose to detect the first phalanx orientation and a stretch sensor applied between the first and the second phalanx to recognize the flection angle. The configuration is completed with a microcontroller unit (ATmega328P) and a Bluetooth Low Power Module (RN4871) to ensure a reliable and easy to implement communication channel. We conduct two main set of tests to verify the global functionalities. In the first set the device is used to track the full flexion of a single finger while in the second we test the device capability to recognize different grabbed objects starting from the data retrieved from two fingers. The preliminary results open the possibility of a future development focused on a modular device composed by five elements, one for each hand finger and able to detect complex gesture like pinch, spread or tap.

Recent technological advancementsAmedeo, Cesta in Internet of Things and Cyber-Physical systems are fostering the diffusion of smart environments relying on sensor networksLuca, Coraci. Indeed, large and heterogeneous amount of data can beGabriella, Cortellessa provided by sensors deployed in user environments providing valuable knowledge to addressRiccardo, De Benedictis different user needs and enabling more effective and reliable solutionsAndrea, Orlandini as well as ensuring personalizationAlessandra, Sorrentino and dynamic adaptation. This paper presents a recent research initiative whose aim isAlessandro, Umbrico to realize autonomous and socially interacting robots by integrating sensor data representation and knowledge reasoning with decision making functionalities within a cognitive control architecture, called Knowledge-based cOntinuous Loop (KOaLa).

Foot ulcer is a severe complication affecting about 25% of diabetes mellitus patients due to a lower blood supply and loss of foot sensitivity (neuropathy). A fast and reliable identification of foot pressure loads and temperature distributions changes on the plantar surface allows to prevent and reduce the consequences of ulceration such as foot or leg amputation. Several wearable technologies have been developed and tested by the scientific community, addressing the “diabetic foot” topic. However, the dimensions of the devices and the combined pressure/temperature monitoring capabilities don’t accommodate the requirements from both the end-users and caregivers: normally just one information—pressure loads or temperature map—is acquired, moreover the amount of thermal reading points is lower than 5 and the accuracy of thermal sensors is greater than 0.5 °C. This work presents a smart insole in which both temperature and pressure data in 8 reading points are monitored in remote way for the assessment of the health foot conditions by a caregiver. Minimally invasive and low power temperature and force sensors have been chosen and integrated into two antibacterial polyurethane-based layers architecture, designed in accordance with the typical requirements of diabetic foot. Based on the results, the developed system shows high performance in terms of temperature and pressure detection.

In this paper, the authors have investigated the possibility of evaluating the well-being of the user, in relation to external stimuli, by means of continuous monitoring of physiological quantities. This preliminary analysis has interested the extraction of features from Electro-Dermal Activity (EDA) signal and their correlation with different emotional states (i.e., Arousal). A low-cost system for continuous monitoring of EDA has been described, together with the experimental setup and the processing techniques applied. A unique indicator, which combines the features extracted from the raw waveform, has been discussed in the paper and applied in post-processing. The implementation of the processing algorithms and the computation of the novel indicator allow to discriminate, with a statistical significance, the user perception, in case of high emotion events (i.e., from low level Arousal < 3 to high level one, > 6). More investigation is needed to improve the processing technique and validate the preliminary results obtained.

The possibility to scavenge energy from vibration and to measure, at the same time, additional information, such as physical characteristics of the incoming source of energy, is of great interest in the modern research. This includes autonomous sensing elements, smart transducers and innovative methods of measurements also in the context of “industry 4.0”. The pursued approach concerns an electromagnetic transducer able to harvest energy coming from the environment (kinetic source of energy), as consequence, charges will be accumulated inside a storage capacitor. It is also capable to measure the mechanical power and transmits the information by using an optical method. It is worth noting that the proposed architecture works without conditioning circuits or active elements. The smart transducer for energy scavenging is designed and experiments are performed showing the suitability of the proposed device.

The demand for harvesting energy from ambient has increased due to the advancement in the field of smart autonomous systems where a self-power source is needed. Kinetic vibration presents one of the main interesting and available source in the environment. However, to store energy from such source, different design requirements should be achieved considering the environmental vibration properties (hundreds of Hz and at low vibration levels, less than few m/s2). It should be also noted that only hundreds of mV can be generated from vibration converters. In this work, an energy harvester system based on an electromagnetic converter and a passive energy management circuit based on the Random Mechanical Switching Harvester on Inductor (RMSHI) architecture are developed. Results show that also in presence of a generated voltage less than 100 mV, it is possible to store the energy inside a load capacitor. Further, the use of the proposed approach, based on mechanical and passive switch, enables to improve significantly the voltage outcome.

Conductive scaffolds are highly used in tissue engineering for bone defect, nerve regeneration, cardiac tissue constructs and many others. Currently, most methods for monitoring cell activities on scaffolds are destructive and invasive such as histological analysis. The research aimed at sensorizing and characterizing a porous gelatin/chitosan scaffold, hence this “Intelligent Scaffold” can behave as a biosensor for evaluating cell behaviour (cell adhesion, proliferation) along with directing cellular growth. Thus, in this research, three-dimensional (3D) gelatin based scaffold has been transformed into conductive scaffold and both the scaffolds are characterized and compared in terms of their electrical conductivity. Carbon black has been used as a doping material to fabricate a Carbon-Gelatin composite conductive scaffold. The scaffolds are prepared by Freeze drying method and carbon black has been homogeneously embedded throughout the gelatin matrix. The scaffold behaviour was characterized by Bio-impedance Spectroscopy method. The preliminary experimental results showed that the conductivity of carbon-gelatin/chitosan scaffold increases around 10 times as compared to simple gelatin scaffold. Thus, these results elucidated the importance of carbon black clustering for development of a conductive network. This shows that carbon black provides conducting path and hence in future, even a small change of cellular activity can be determined by impedance fluctuation within the scaffold.

The knowledge of material properties like Young’s modulus and residual stress is crucial for a reliable design of devices with optimized performance. Several works discussed on the determination of the mechanical properties of thin/thick films and microstructures from deflection measurements by a profiler. This work provides an approximate solution for the load-deflection response of perforated membranes clamped on two opposite edges subjected to quasi-point pressure loads applied by a profilometer. SixNy/a-Si/SixNy thin film membranes of different sizes and porosities were fabricated by unconventional 100 °C PECVD process using surface micromachining approach. Tri-layer thin films were mechanically characterized by nanoindentation tests and residual stress measurements based on the wafer curvature method. Load-deflection measurements were done by applying quasi-point loads in the range 4.9–9.8 μN. Finite Element Analysis was used to model the mechanical behavior of the membrane, in agreement with the deflection data measured by profilometer. The elastic modulus measured by nanoindentation was used as reference for the perforated membranes load-deflection analytical function identification. An approximate analytical law was developed, which explicates the maximum deflection amplitude as a function of geometric features (sizes and thickness) and mechanical properties (Young’s modulus and residual stress). It was validated numerically and experimentally; it was able to provide an estimation of the residual stress of CCFF perforated membranes, starting from measured data of deflection, for single or multiple loads; also, it can be used in a complementary way to calculate the Young’s modulus from deflection data and residual stress information.

The non-destructive testing based on eddy currents (EC-NDT) is an in-field inspection technique mainly used to detect and characterize defects in conductive materials. This technique is adopted in many industrial, manufacturing and aerospace applications. Today, in aeronautical and industrial applications, new thin carbon fiber materials often substitute metallic materials as aluminum, copper and so on. Therefore, the actual trend of EC-NDT is the in-field inspection of these very thin materials. Considering the skin depth of induced eddy current, the thinness of these materials imposes the use of higher frequencies than those typically adopted in traditional tests. Due to the inductive load of the excitation coil, the voltage required to obtain the desired current values could reach very high values. The use of resonant excitation circuits could mitigate this problem. The article describes the effect of some real resonant circuits on the improvement of feeding high-frequency EC-NDT probes in terms of required voltage and power.