文献类型：期刊文献

英文题名：A pH dependent thermo-sensitive copolymer drug carrier incorporating 4-amino-2,2,6,6-tetramethylpiperidin-1-oxyl (4-NH₂-TEMPO) residues for electron spin resonance (ESR) labeling

作者：Yu, Ronghua[1,2];Zhao, Hongli[1,2];Zhao, Zijun[1,2];Wan, Yuanyuan[1,2];Yuan, Huihui[1,2,3];Lan, Minbo[1,2,3,4];Lindoy, Leonard F.[5];Wei, Gang[6]

机构：[1]E China Univ Sci & Technol, Shanghai Key Lab Funct Mat Chem, Shanghai 200237, Peoples R China;[2]E China Univ Sci & Technol, Res Ctr Anal & Test, Shanghai 200237, Peoples R China;[3]E China Univ Sci & Technol, Key Lab Ultrafine Mat, Minist Educ, Shanghai 200237, Peoples R China;[4]E China Univ Sci & Technol, State Key Lab Bioreactor Engn, Shanghai 200237, Peoples R China;[5]Univ Sydney, Sch Chem, Sydney, NSW 2006, Australia;[6]CSIRO Mat Sci & Engn, Lindfield, NSW 2070, Australia

年份：2011

卷号：362

期号：2

起止页码：584

外文期刊名：JOURNAL OF COLLOID AND INTERFACE SCIENCE

收录：;WOS:【SCI-EXPANDED(收录号:WOS:000294142500044)】；

基金：This work was supported by the Ministry of Science and Technology of the People's Republic of China (Contract No. 2010DFA44300), National Natural Science Foundation of China (NSFC, Contract No. 21074033) and the Science and Technology Commission of Shanghai Municipality (STCSM, Contract No. 10dz2220500 and No. 09520703200).

语种：英文

外文关键词：pH; Thermo-sensitive copolymer; TEMPO (2,2,6,6-tetramethylpiperidin-1-oxyl); Micelles; Electron spin resonance (ESR)

摘要：The fabrication of a new amphiphilic block copolymer composed of a poly DL-lactic acid (PLA) hydrophobic backbone and pH dependent thermo-sensitive poly (N-isopropyl) methacrylamide-co-N-isopropylmaleamic acid-co-10-undecenoic acid (PNIPAAm-co-NIPMMA-co-UA) entities as hydrophilic domains as well as carrying 2,2,6,6-tetramethylpiperidin-1-oxyl (TEMPO) residues for electron spin resonance (ESR) labeling is reported. The lower critical solution temperature (LCST) of the copolymer was determined by optical absorbance measurements. The LCST was pH dependent and varied in a narrow practical range, 35.4 degrees C at pH 5.0, 37.5 degrees C at pH 6.5 and 39.4 degrees C at pH 7.4, which was below, near and above nominal physiological temperature respectively. The assembly of the copolymer into micelles in aqueous solution at temperatures below the LCST was confirmed by FT-IR, H-1 NMR and fluorescence spectroscopy. It is demonstrated that the anticancer drug, 5-fluorouracil (5-FU) can be loaded effectively within the polymeric micelles and released in response to environmental stimuli- namely, pH and temperature. Crown Copyright (C) 2011 Published by Elsevier Inc. All rights reserved.