The present study describes the facile preparation of acid/CO2 stimuliresponsive sheddable nanoparticles based on carboxymethylated chitosan(CMCS).Commercially available CMCS was grafted with monomethoxy polyethylene ...The present study describes the facile preparation of acid/CO2 stimuliresponsive sheddable nanoparticles based on carboxymethylated chitosan(CMCS).Commercially available CMCS was grafted with monomethoxy polyethylene glycol(mPEG)chains via an acid/CO2 responsive linker,i.e.,benzoic-imine,and then was used for the cross-linking with CaCI2.With a high CMCS concentration up to 7 mg/mL,stable nanoparticles were successfully prepared.The particle size grew slightly with increasing the molecular weight of mPEG.When the concentration of CaCI2 and the feed ratio of CMCS to mPEG increased,the particle size decreased at first and then increased after reaching a minimum size.When the particles were stimulated by CO2 or acid,benzoic.imine cleaved quickly,and mPEG fell off the nanoparticles simultaneously,and then flocculation and precipitation occurred.These sheddable nanoparticles might have potential application in the biomedical field in eluding the intelligent drug delivery system.展开更多
基金This work was supported by the Natural Science Foundation of Hubei Province(2016CFB329)the Science and Technology Research Program of Hubei Provincial Department of Education(B2016260)the Scientific Research and Technological Development Program of Jingmen City(YFYB2016021).
文摘The present study describes the facile preparation of acid/CO2 stimuliresponsive sheddable nanoparticles based on carboxymethylated chitosan(CMCS).Commercially available CMCS was grafted with monomethoxy polyethylene glycol(mPEG)chains via an acid/CO2 responsive linker,i.e.,benzoic-imine,and then was used for the cross-linking with CaCI2.With a high CMCS concentration up to 7 mg/mL,stable nanoparticles were successfully prepared.The particle size grew slightly with increasing the molecular weight of mPEG.When the concentration of CaCI2 and the feed ratio of CMCS to mPEG increased,the particle size decreased at first and then increased after reaching a minimum size.When the particles were stimulated by CO2 or acid,benzoic.imine cleaved quickly,and mPEG fell off the nanoparticles simultaneously,and then flocculation and precipitation occurred.These sheddable nanoparticles might have potential application in the biomedical field in eluding the intelligent drug delivery system.