Development of X-ray opaque poly(lactic acid) end-capped by triiodobenzoic acid towards non-invasive micro-CT imaging biodegradable embolic microspheres. (November 2018)

• Record Type: Journal Article
• Authors: Wang, Wenhuan; Wei, Zhiyong; Sang, Lin; Wang, Yongxuan; Zhang, Jie; Bian, Yufei; Li, Yang
• Is Part Of: European polymer journal. Volume 108(2018)
• Page Start: 337
• Page End: 347
• Publication Date: 2018-11
• Subjects: Radiopaque -- Poly(lactic acid) microspheres -- Micro-CT imaging -- Degradation behavior; Polymers -- Periodicals; Polymerization -- Periodicals; Polymères -- Périodiques; Polymérisation -- Périodiques; Polymerization; Polymers; Periodicals; Electronic journals; 547.705
• DOI: 10.1016/j.eurpolymj.2018.09.018
• Languages: English
• ISSNs: 0014-3057

Abstract

Graphical abstract: Highlights: End-group modification of poly(lactic acid) towards X-ray opaque materials. Poly(lactic acid) was end-capped with triiodobenzoic acid. Non-invasive micro-CT imaging biodegradable embolic microspheres were developed. In vitro degradation behavior of X-ray opaque microspheres was traced. Abstract: Non-invasive micro-CT imaging functionalized biodegradable polymeric microspheres for interventional embolization are gaining increasing attention recent years. We herein report a facile method of end-group modification to prepare X-ray opaque poly(lactic acid) (PLA) using triiodobenzoic acid (TIBA) as end-capping agent, and develop the inherently radiopaque poly(lactic acid) materials towards embolic microspheres traceable with non-invasive micro-CT imaging. Two types, that is, linear 2-arm and star 4-arm, of TIBA terminated PLA were designed and successfully synthesized by 1 H NMR characterization. Then these PLA materials were used to fabricate polymeric microspheres with well-controlled size (100–200 μm) by W/O emulsification method. As expected, the star 4-arm TIBA terminated poly(lactic acid) (I-S-PLA) microspheres possessed higher iodine content and exhibited greater radiopacity compared with linear 2-arm analogue (I-L-PLA). Both these microspheres showed low cytotoxicity and controllable micro-CT imaging. Furthermore, the effects of linear and star structure of I-PLA microspheres on in vitro degradation behavior was investigated by GPC, micro-CT, SEM and EDS. The degradable results revealed that iodine content of I-L-PLA decreased faster than that of I-S-PLA, which resulted in a further attenuation in micro-CT imaging. Consequently, CT-imaging of I-S-PLA microspheres did not drop sharply over degradation period, exhibiting higher HU values than aluminum wedge of 2 mm. These findings suggested that the biodegradable radiopaque poly(lactic acid) microspheres could be traceable by non-invasive micro-CT imaging, which are promising embolic agents.