Synthesis, characterization and evaluation of pegylated-citric acid based dendrimers as drug delivery agents

In the present study, four different types of fourth-generation pegylated citric acid based dendrimers namely PE/TMP-MC-PEG-CA-PEG and PE/TMP-MS-PEG-CA-PEG were synthesized. The dendrimers were further conjugated with cefotaxime (CFTX) sodium drug. The structures of these dendrimers and drug-dendrimer conjugates were confirmed by using ¹H-NMR, ¹³C-NMR, and FTIR spectroscopy. The confirmation of particle size, surface topography and structure of drug-dendrimer conjugates was done using Zeta sizer, AFM, and HR-TEM techniques. Cytotoxicity investigation revealed that the CFTX-encapsulated dendrimers are safe against normal epithelial cells and showed 20–22% anticancer activity against A549 Lung carcinoma cells; besides that, the synthesized dendrimers and drug-dendrimer conjugates also showed 15–28% and 2–3% hemolytic toxicity, respectively, against red blood cells (RBC). The antibacterial activity of all synthesized third and fourth generation drug-dendrimer conjugates were investigated on Gram-positive and Gram-negative bacteria. The results show that drug conjugate with third generation dendrimers depicted a greater effective zone of inhibition (ZOI) as compared to fourth generation drug-dendrimer conjugates against these pathogenic bacteria.