Release Time:2019-03-13 Hits:
Indexed by: Journal Article
Date of Publication: 2018-11-01
Journal: EUROPEAN POLYMER JOURNAL
Included Journals: Scopus、SCIE
Volume: 108
Page Number: 337-347
ISSN: 0014-3057
Key Words: Radiopaque; Poly(lactic acid) microspheres; Micro-CT imaging; Degradation behavior
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 H-1 NMR characterization. Then these PLA materials were used to fabricate polymeric microspheres with well-controlled size (100-200 mu m) 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 micro spheres 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.