Stimuli-re sponsive polypeptides have been intensively investigated fo r controlled drug release,owing to their favorable biocompatibility and biodegradability.In this work,we designed and synthesized a new kind of po...Stimuli-re sponsive polypeptides have been intensively investigated fo r controlled drug release,owing to their favorable biocompatibility and biodegradability.In this work,we designed and synthesized a new kind of polypeptide bearing 1,4-dithiane pendants for reactive oxygen species(ROS)-responsive drug release.The polypeptide-based block copolymer was facilely synthesized by ring-opening polymerization(ROP)of 1,4-dithian-substituted L-glutamate N-carboxyanhydride(DTG-NCA)monomer using an amino-terminated poly(ethylene glycol)methyl ether(mPEG-NH2)as the macro molecular initiator.The resulta nt block copolyme r,mPEG-b-PDTG,could self-assemble into unifo rm micelles in aqueous medium owing to its amphiphilic structure.Then,the H2 O2-triggered oxidation behaviors of the mPEG-b-PDTG micelles were studied by dynamic light scattering(DLS),FT-IR and turbidimetric assay.It was revealed that the oxidation of thioether into sulfoxide in the side chains would result in disassembly of the micelles.Furthermore,the ROS-responsive drug release behavior of the mPEG-b-PDTG micelles was verified by using Nile Red as a model drug.MTT assay also proved that mPEG-b-PDTG was non-toxic in B16 F10 and L929 cells.Therefore,such a new class of oxidation-responsive polypeptide might provide a promising platform for ROS-responsive drug delivery.展开更多
基金financially supported by National Key Research and Development Program of China(No.2016YFC1100701)the National Natural Science Foundation of China(Nos.51573184,51520105004 and 51833010)the Youth Innovation Promotion Association of Chinese Academy of Sciences(No.2017266)。
文摘Stimuli-re sponsive polypeptides have been intensively investigated fo r controlled drug release,owing to their favorable biocompatibility and biodegradability.In this work,we designed and synthesized a new kind of polypeptide bearing 1,4-dithiane pendants for reactive oxygen species(ROS)-responsive drug release.The polypeptide-based block copolymer was facilely synthesized by ring-opening polymerization(ROP)of 1,4-dithian-substituted L-glutamate N-carboxyanhydride(DTG-NCA)monomer using an amino-terminated poly(ethylene glycol)methyl ether(mPEG-NH2)as the macro molecular initiator.The resulta nt block copolyme r,mPEG-b-PDTG,could self-assemble into unifo rm micelles in aqueous medium owing to its amphiphilic structure.Then,the H2 O2-triggered oxidation behaviors of the mPEG-b-PDTG micelles were studied by dynamic light scattering(DLS),FT-IR and turbidimetric assay.It was revealed that the oxidation of thioether into sulfoxide in the side chains would result in disassembly of the micelles.Furthermore,the ROS-responsive drug release behavior of the mPEG-b-PDTG micelles was verified by using Nile Red as a model drug.MTT assay also proved that mPEG-b-PDTG was non-toxic in B16 F10 and L929 cells.Therefore,such a new class of oxidation-responsive polypeptide might provide a promising platform for ROS-responsive drug delivery.