Preparation and characterization of chitosan/sepiolite bionanocomposites for tetracycline release

Chitosan/sepiolite (CS/SEP) bionanocomposite films have been prepared and characterized with Fourier transform infrared spectroscopy, thermogravimetric analysis (TGA), X‐ray diffraction, and scanning electron microscopic analysis. The results indicated the formation of a phase separated microcomposite structure at low and high content of SEP. The point of zero charge was determined as neutral pH. The thermal behavior of the samples was examined by TGA/derivative thermogravimetric (DTG) analysis. The dispersed clay improved the thermal stability of the matrix systematically with the increase of clay loading. The release of Tetracycline (TC) was also studied in a batch system as function of pH, clay content, and contact time at 37°C. Increase in the clay content of the composite resulted decrease in the release of TC due to the interaction of the silanol groups ( SiOH) of the clay and the  OH groups of the drug by the formation of the hydrogen bonding. Diffusion rate of TC to aqueous medium decreased by increasing SEP content. POLYM. COMPOS., 38:1810–1818, 2017. © 2015 Society of Plastics Engineers