the effect of cryoprotectant on chitosan nanoparticles

nowadays, some novel drug delivery systems such as polymeric nanoparticles are designed to control drug release. chitosan as a polysaccharide and its biocompatibility, biodegradation and antibacterial properties, has been a carrier for delivery of different peptide. due to the controlled and sustained release of drug, chitosan nanoparticles cause to decrease dosage drug with less side effects. one of the problems in preparation of chitosan nanoparticles is aggregation of them with dimension of micro and film formation that result undesirable release profile. the aim of this study was inhabitation of nanoparticles aggregation by addition of different cryoprotectant to the medium after particles formation. in this study chitosan vancomycin loaded were prepared by ionic gelation method. to prevent aggregation of vancomycin loaded nanoparticles, glycerol, sucrose and trehalose were added to the medium. the effect of these cryoprotectants on size, shape and drug release profile of nanoparticles was investigated. the size and shape of nanoparticles were analyzed by dynamic light scattering (dls) and scanning electron microscope (sem). addition of cryoprotectants to the medium after preparation of vancomycin loaded chitosan nanoparticles resulted in less aggregation of nanoparticles with consequent improvement of drug release profile among different studied surfactants. trehalose was more effective for preventation particles aggregation and the size of nanoparticles changed from 134 to 159 ηm in the presence of this cryoprotectant.