A new method to synthesize a degradable terminal amino group-containing copolymer,poly(ethylene glycol)-b- poly(ε-caprolactone)(MPEG-PCL-NH_2),was developed in the following three steps:(1)the ring-opening polymeriza...A new method to synthesize a degradable terminal amino group-containing copolymer,poly(ethylene glycol)-b- poly(ε-caprolactone)(MPEG-PCL-NH_2),was developed in the following three steps:(1)the ring-opening polymerization (ROP)ofε-caprolactone from the Schiff base prepared from benzatdehyde and ethanolamine(Ph-CH=NCH_2CH_2OH)used as an initiator to obtain heterobifunctional poly(ε-caprolactone)with one terminal Schiff base group and one hydroxyl group (HO-PCL-CH_2CH_2N=CH-Ph);(2)the coupling reaction of two ...展开更多
In this study,we describe a simple synthesis route to prepare triblock copolymers with disulfide-linkers,poly(ethylene glycol)-SS-poly(ε-caprolactone)-SS-poly(ethylene glycol)(PEG-SS-PCL-SS-PEG)for application in the...In this study,we describe a simple synthesis route to prepare triblock copolymers with disulfide-linkers,poly(ethylene glycol)-SS-poly(ε-caprolactone)-SS-poly(ethylene glycol)(PEG-SS-PCL-SS-PEG)for application in the reductively responsive release of doxorubicin(DOX).To synthesize PEG-SS-PCL-SS-PEG,two end-groups of PCL-diol were first modified with cystamine to introduce disulfide bonds and subsequently conjugated with PEG-NHS via carbodiimide chemistry.PEG-SS-PCL-SSPEG fabricated into polymeric micelles with stable structure and different nanoscale sizes via adjusting the PCL chain length,showing obvious reductive responsiveness and fast drug release of encapsulated DOX in the presence of glutathione(GSH).Moreover,DOX-loaded PEG-SS-PCL-SS-PEG micelles exhibited higher therapeutic efficacy than reduction-insensitive PEG-b-PCL micelles in vitro.Thus,end-groups conjugation is a simple and straightforward strategy to introduce intelligent responsiveness in biocompatible block copolymers and improve their therapeutic efficacy.展开更多
Percutaneous coronary intervention（PCI） has become an important method for the treatment of the pa- tients with coronary heart disease; however, problems, such as vascular endothelial inflammation, late thrombosis, ...Percutaneous coronary intervention（PCI） has become an important method for the treatment of the pa- tients with coronary heart disease; however, problems, such as vascular endothelial inflammation, late thrombosis, and stent restenosis still exist as a result of poor biocompatibility of the materials. To enhance the biocompatibility, methoxy poly（ethylene glycol）（mPEG） was immobilized on the surface of AISI 316 grade stainless steel（SS）（AISI： American Iron and Steel Institute）. First, silanized mPEG was synthesized by the direct coupling of mPEG with 3-isocyanatopropyltriethoxysilane（IPTS） via urethane bonds, and the silanized mPEG was then grafted on the surface of SS that was hydroxylated with piranha solution. The results obtained from contact angle goniometry, X-ray pho- toelectron spectroscopy（XPS）, and atomic force microscopy（AFM） confirm that the mPEG modified steel contained more C and Si and less Fe and Cr on its surface, exhibiting a morphological change and decrease in the contact angle. The biocompatibility of the mPEG modified SS was evaluated with fibrinogen adsorption, platelet activation and adhesion, and human umbilical vein endothelial celI（HUVEC） adhesion. Fibrinogen adsorption, platelet activation, and adhesion were clearly suppressed on the surface-modified steel. In addition, human umbilical vein endothelial cell（HUVEC） could adhere and proliferate on the surface of the mPEG-modified SS. This study indicates that the modification of 316L SS with mPEG could enhance the biocompatibility and provide a primary experimental founda- tion for the development of next-generation coronary stent materials for clinical application.展开更多
Self assembled monolayers(SAMs) of mercapto methoxy poly(ethylene glycol)(MPEG) on gold electrode surface was formed. The SAMs of MPEG had molecular recognition characteristics. The iodine ions could permeate through ...Self assembled monolayers(SAMs) of mercapto methoxy poly(ethylene glycol)(MPEG) on gold electrode surface was formed. The SAMs of MPEG had molecular recognition characteristics. The iodine ions could permeate through the SAM layer to approach the electrode surface. This MPEG film electrode can be used to detect iodine ions with lower interference.展开更多
基金the National Natural Science Foundation of China(No.20574066)National Fund for Distinguished Young Scholar(No.50425309)
文摘A new method to synthesize a degradable terminal amino group-containing copolymer,poly(ethylene glycol)-b- poly(ε-caprolactone)(MPEG-PCL-NH_2),was developed in the following three steps:(1)the ring-opening polymerization (ROP)ofε-caprolactone from the Schiff base prepared from benzatdehyde and ethanolamine(Ph-CH=NCH_2CH_2OH)used as an initiator to obtain heterobifunctional poly(ε-caprolactone)with one terminal Schiff base group and one hydroxyl group (HO-PCL-CH_2CH_2N=CH-Ph);(2)the coupling reaction of two ...
基金This work was supported by the National Natural Science Foundation of China(Project U1704150)the Scientific and Technological Projects of Henan Province(182102410017).
文摘In this study,we describe a simple synthesis route to prepare triblock copolymers with disulfide-linkers,poly(ethylene glycol)-SS-poly(ε-caprolactone)-SS-poly(ethylene glycol)(PEG-SS-PCL-SS-PEG)for application in the reductively responsive release of doxorubicin(DOX).To synthesize PEG-SS-PCL-SS-PEG,two end-groups of PCL-diol were first modified with cystamine to introduce disulfide bonds and subsequently conjugated with PEG-NHS via carbodiimide chemistry.PEG-SS-PCL-SSPEG fabricated into polymeric micelles with stable structure and different nanoscale sizes via adjusting the PCL chain length,showing obvious reductive responsiveness and fast drug release of encapsulated DOX in the presence of glutathione(GSH).Moreover,DOX-loaded PEG-SS-PCL-SS-PEG micelles exhibited higher therapeutic efficacy than reduction-insensitive PEG-b-PCL micelles in vitro.Thus,end-groups conjugation is a simple and straightforward strategy to introduce intelligent responsiveness in biocompatible block copolymers and improve their therapeutic efficacy.
文摘Percutaneous coronary intervention（PCI） has become an important method for the treatment of the pa- tients with coronary heart disease; however, problems, such as vascular endothelial inflammation, late thrombosis, and stent restenosis still exist as a result of poor biocompatibility of the materials. To enhance the biocompatibility, methoxy poly（ethylene glycol）（mPEG） was immobilized on the surface of AISI 316 grade stainless steel（SS）（AISI： American Iron and Steel Institute）. First, silanized mPEG was synthesized by the direct coupling of mPEG with 3-isocyanatopropyltriethoxysilane（IPTS） via urethane bonds, and the silanized mPEG was then grafted on the surface of SS that was hydroxylated with piranha solution. The results obtained from contact angle goniometry, X-ray pho- toelectron spectroscopy（XPS）, and atomic force microscopy（AFM） confirm that the mPEG modified steel contained more C and Si and less Fe and Cr on its surface, exhibiting a morphological change and decrease in the contact angle. The biocompatibility of the mPEG modified SS was evaluated with fibrinogen adsorption, platelet activation and adhesion, and human umbilical vein endothelial celI（HUVEC） adhesion. Fibrinogen adsorption, platelet activation, and adhesion were clearly suppressed on the surface-modified steel. In addition, human umbilical vein endothelial cell（HUVEC） could adhere and proliferate on the surface of the mPEG-modified SS. This study indicates that the modification of 316L SS with mPEG could enhance the biocompatibility and provide a primary experimental founda- tion for the development of next-generation coronary stent materials for clinical application.
文摘Self assembled monolayers(SAMs) of mercapto methoxy poly(ethylene glycol)(MPEG) on gold electrode surface was formed. The SAMs of MPEG had molecular recognition characteristics. The iodine ions could permeate through the SAM layer to approach the electrode surface. This MPEG film electrode can be used to detect iodine ions with lower interference.
