Cephalosporin release from functionalized MCM-41 supports interpreted by various models

Few systematic studies on cephalosporin (CFS) antibiotic release from functionalized porous supports have been reported. The present work is focused on developing kinetic release experimental investigations of three CFS (cefotaxime, cefalotin, cefuroxime) in a synthetic intestinal fluid by using a mesoporous silica MCM-41 carrier, unfunctionalized or functionalized with hydrophilic (3-aminopropyl triethoxysilane, APTES) or hydrophobic (triethoxyvinylsilane, VTES) linker groups. An extended kinetic model, including complex adsorption-desorption and diffusion steps, has been used to correlate the drug-linker-carrier characteristics to the release rate under various release conditions. The extended model parameters and predictions have been interpreted for significance and compared with those of simplified diffusional models in terms of quality, by pointing out the loss of information when the reduced models are used for designing controlled release systems. (C) 2012 Elsevier Inc. All rights reserved.