Choi, Jiyeon Jang, Bu Nam Park, Bang Ju Joung, Yoon Ki Han, Dong Keun 2024-01-20T09:03:09Z 2024-01-20T09:03:09Z 2021-09-02 2014-08-26 0743-7463 https://pubs.kist.re.kr/handle/201004/126448 Sirolimus (SRL) release from the biodegradable poly(L-lactic-co-glycolic acid) (PLGA) matrix was investigated for the application of drug-eluting stents (DES). In particular, this study focused on whether various organic solvents affect the interaction between SRL and PLGA and the formation of microstructures during ultrasonic coating. The SRL-loaded PLGA coated by tetrahydrofuran or acetone showed a significant initial burst, whereas that from acetonitrile was constantly released during a period of 21 days. On the basis of these results, the interactions at the molecular level of SRL with the polymer matrix were estimated according to various organic solvents. Although the topographies of the coated surface were obviously different, the correlation between surface roughness and SRL release was very poor. Irrespective of organic solvents, FT-IR data showed significantly weak SRL-PLGA interactions. From the result of wide-angle X-ray diffraction, it was confirmed that SRL was dispersed in an amorphous state in the polymer matrix after ultrasonic coating. The glass-transition temperature was also influenced by organic solvents, resulting in a plasticizing effect. The particle size of SRL appeared to determine the release profile from the PLGA matrix, which was the combination of diffusion and polymer degradation at an SRL size of more than 800 nm and the Fickian release at that of less than 300 nm. Therefore, organic solvents can lead to a heterogeneous microstructure in the SRL-loaded PLGA matrix, which is at or near the surface, consisting of aggregated drug- and polymer-rich regions. It is expected that the drug release can be controlled by physicochemical properties of organic solvents, and this study can be used effectively for localized drug release in biomedical devices such as drug-eluting stents. English AMER CHEMICAL SOC SOLID DISPERSIONS DELIVERY SYSTEMS CORONARY-ARTERY PHYSICAL STATE IN-VITRO COATINGS NANOPARTICLES KINETICS POLY(D,L-LACTIDE-CO-GLYCOLIDE) MICROSTRUCTURE Effect of Solvent on Drug Release and a Spray-Coated Matrix of a Sirolimus-Eluting Stent Coated with Poly(lactic-co-glycolic acid) Article 10.1021/la500452h 1 LANGMUIR, v.30, no.33, pp.10098 - 10106 LANGMUIR 30 33 10098 10106 scie scopus 000340993200028 2-s2.0-84906663711 Chemistry, Multidisciplinary Chemistry, Physical Materials Science, Multidisciplinary Chemistry Materials Science Article SOLID DISPERSIONS DELIVERY SYSTEMS CORONARY-ARTERY PHYSICAL STATE IN-VITRO COATINGS NANOPARTICLES KINETICS POLY(D,L-LACTIDE-CO-GLYCOLIDE) MICROSTRUCTURE