Journal of Polymer Science Part A: Polymer Chemistry, Vol.52, No.17, 2399-2411, 2014
Synthesis and Characterization of D-(-)-Salicine-Based Star Copolymers Containing Pendant Carboxyl Groups with Fluorophore Dyes
Salicin was modified to monoacetals and diacetals with bromoester groups (f(Br)=4 and 6) initiating atom transfer radical polymerization (ATRP). These glucoinitiators were used to synthesize 4- and 6-arm star copolymers of tert-butyl methacrylate (tBMA) and methyl methacrylate (MMA) with different arm polymerization degree (DParm=13-79), and composition (25-75 mol % of tBMA). The transformation of hydrophobic stars into amphiphilics by acidolysis of tert-butyl groups resulted in copolymers with various contents of hydrophilic fraction based on methacrylic acid (MAA) units (13-75 mol %), which were labeled with fluorescein amine (FA) for the future studies of targeted internalization. The UV spectroscopy and fluorescence measurements of the prepared copolymers confirmed the incorporation of fluorophore moieties (1-14 FA labeled units as max. 5% of total MAA units). The solution properties of star polyacids observed by DLS in a function of a pH show a specific behavior related to the interchain/intrachain interactions yielding particles with diameter sizes in the range from 3 to 15 nm, which can be significantly increased to 180-270 nm by addition of NaCl. (c) 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 2399-2411