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Indexed by:Journal Papers

Date of Publication:2020-06-01

Journal:POLYMER DEGRADATION AND STABILITY

Included Journals:SCIE

Volume:176

ISSN No.:0141-3910

Key Words:X-ray opaque; Linear-comb poly(lactic acid); Microspheres; Micro-CT imaging; Hydrolytic degradation

Abstract:Biodegradable polyesters with X-ray visibility for biomedical applications have attracted increasing attention. We herein reported a facile method of end-chain functionalization to prepare highly branched linear-comb poly (lactic acid) (Lc-PLA) using triiodobenzoic acid (TIBA) as end-capping and X-ray contrast agent. Three branch lengths of iodinated linear-comb poly (lactic acid) (I-Lc-PLA(30k), I-Lc-PLA(50k), and I-Lc-PLA(70k)) were successfully synthesized and then microspheres with well-controlled size (average size similar to 180 mu m) were prepared. By micro-CT testing, the results showed that shorter branch length of PLA contributed more iodinated end-group functionalized sites, leading a relatively high iodine content and excellent radiopacity. After terminated with TIBA, glass transition temperature and thermal stability of I-Lc-PLA polymers were greatly improved. During the in vitro hydrolytic degradation of three months, the molecular weight, iodine content, surface microstructure and micro-CT radiopacity of these microspheres were investigated. The degradation results showed that I-Lc-PLA(50k) possessed sufficient iodine content and high household unit values, suggesting a well-maintained radiopacity of I-Lc-PLA. Therefore, this work proposed a highly branched I-Lc-PLA microspheres with promising CT-imaging capacity, which could be used as a long-term embolic material. (C) 2020 Elsevier Ltd. All rights reserved.