PLGA-(L-Asp-alt-diol)(x)-PLGAs with different contents of pendant amino groups: synthesis and characterization.
A series of novel biodegradable multi-block copolymers PLGA-(L-Asp-alt-diol)(x)-PLGA with pendant amino groups was synthesized by ring-opening polymerization of D,L-lactide/glycolide(D,L-LA/GA) (75/25) using poly(N-Cbz-L-Asp-alt-diol)s as macroinitiator and stannous octoate as catalyst, in which the N-Cbz-L-Asp represents N-carbobenzyloxy-L-aspartic acid and diols are ethylene glycol, triethylene glycol, PEG200, and PEG600, respectively. Their structures and properties were characterized by FTIR, (1)H NMR, DSC, GPC, and elemental analysis (EA). The contents of the L-Asp unit in the copolymers were increased from 12.9 to 79.3 mmol.g(-1) with decreasing the chain length of the diol, while the glass transition temperatures of the copolymers were decreased from 27.1 to 11.7 degrees C with increasing the chain length of the diol. Thus, the results in this study provide a way to prepare biomaterials with different L-Asp unit densities or different number of bioactive sites as well as different properties through adjusting the chain length of the diol. Synthesis of PLGA-(N-Cbz-L-Asp-alt-diol)(x)-PLGA copolymers.
Institute of Polymer Science, School of Chemistry and Chemical Engineering, Sun Yat-sen University, Guangzhou 510275, China.
Jie
J
Zhao
Daping
D
Quan
Kairong
K
Liao
Qing
Q
Wu
D001216:Asparagine / Q000737:chemistry*; D001672:Biocompatible Materials / Q000138:chemical synthesis / Q000737:chemistry*; D019344:Lactic Acid / Q000138:chemical synthesis / Q000737:chemistry*; D015394:Molecular Structure; D011100:Polyglycolic Acid / Q000138:chemical synthesis / Q000737:chemistry*; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011108:Polymers / Q000138:chemical synthesis / Q000737:chemistry*
D001672:Biocompatible Materials; D011108:Polymers; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; D001216:Asparagine