One-pot synthesis of hollow mesoporous carbon materials and their drug release properties

In this study, a simple route for the synthesis of hollow mesoporous carbon materials (HMCMs) with adjustable shell thicknesses via a one-pot strategy for direct carbonization and etching was developed. HMCMs were examined as a carrier matrix for the delivery of tetracycline hydrochloride (TH). The thickness of the mesoporous shell could be tuned between 7 and 90 nm by changing the amount of cetyltrimethylammonium bromide and composition of the polymer precursor. The obtained materials were characterized by transmission electron microscopy, scanning electron microscopy, X-ray diffraction, thermogravimetric analysis, and N₂ adsorption–desorption isotherms. The optimum conditions for the synthesis of the HMCM spheres were systematically investigated. The synthesized materials possessed specific surface areas of 710–954 m² g⁻¹ and average pore diameters of 3.8 nm. The performance of the HMCMs towards the delivery of TH was tested in vitro in an aqueous bath at 37 °C; the release of TH from these drug delivery systems was monitored by UV–Vis spectroscopy. Results demonstrated that by adjusting the mesoporous carbon shell thickness of the HMCMs, high TH adsorption capacities (722–850 mg g⁻¹) and tunable higher drug releases ranging from 15 to 25 h and sustained lower drug releases over the subsequent ~30 h were achieved.