writer：Yuji Pu, Longgui Zhang, Hui Zheng, Bin He*, Zhongwei Gu*
keywords：star shape poly(benzyl L-aspartate)-b-poly(ethylene glycol) copolymers
source：期刊
specific source：Macromol. Biosci. 2014, 14(2): 289-97
Issue time：2014年
Star shape amphiphilic block copolymers with polyhedral oligomeric silsesquioxanes as cores were synthesized using the “arm-first” strategy. Firstly, the block copolymer poly(benzyl L-aspartate)-b-poly(ethylene glycol) (PBLA-b-PEG) was synthesized via ring-opening polymerization of β-benzyl L-aspartate-N-carboxyanhydride (BLA-NCA) with α-Methoxy-ω-aminopoly(ethylene glycol) (mPEG-NH₂) as a macroinitiator. The copolymers were then immobilized on the eight groups of polyhedral oligomeric silsesquioxanes (POSS-COOH). The star shape copolymers were characterized by ¹H NMR, FTIR, and GPC. The star shape block copolymers (POSS-g-(PBLA-b-PEG)) self-assembled into micelles in aqueous medium. The CMC of the micelles was tested by fluorescence spectroscopy. Quercetin was used as a model drug and trapped in the micelles to study the potency of micelles as drug carriers. The drug loading content and encapsulation efficiency increased with increasing the chain length of PBLA blocks. Low burst release rate was observed in the drug loaded micelles and the release behavior fitted to zero-order after the burst release. The cytotoxicity assay demonstrated that the POSS-g-(PBLA-b-PEG) copolymers were nontoxic. The star shape block copolymersare potential carriers for anticancer drug delivery.