Polyethylene glycol effects on the performance of rifampicin-polylactic acid-glycolic acid polymer microspheres

Yang Zong-qiang; He Ying; Shi Jian-dang

doi:10.3969/j.issn.2095-4344

Abstract：BACKGROUND:Polylactic acid as a carrier has good biocompatibility, but the burst release of microspheres seriously affects their clinical application. <br> OBJECTIVE:To investigate the effects of polyethylene glycol on rifampicin-polylactic acid-glycolic acid microspheres in terms of morphologies, drug loading, encapsulation efficiency, in vitro release and burst release. <br> METHODS: Polylactic acid-glycolic acid polymer was used as a carrier, and polyethylene glycol-rifampicin-polylactic acid-glycolic acid polymer microspheres (experimental group) and rifampicin-polylactic acid-glycolic acid polymer microspheres were prepared using W/O/W emulsifying-solvent evaporation technique. The characteristics of two kinds of microscopes were observed by scanning electron microscopy, drug concentration and cumulative release of rifampicin in the simulated body fluid were detected using high performance liquid chromatography during different periods, and drug loading as wel as encapsulation efficiency was also determined in the two groups. <br> RESULTS AND CONCLUSION: Compared with the control group, in the experimental group, the microspheres were found smooth surface, even distribution, decreased particle size and good dispersion, and the drug loading and encapsulation efficiency were evidently higher. In the experimental group, the largest amount of drug release of the microspheres was within 3 hours, the drug release tended to be stable at 1 day, and the cumulative drug release was less than 20% in1 day. In the control group, the largest amount of drug release was within 3 hours, but the amount was about 1.5 times than that of the experimental group, the drug release also tended to stable at 1 day. The study has shown that polyethylene glycol can improve the peletizing ratio and reduce the particle size of rifampicin-polylactic acid-glycolic acid microspheres, increase the drug loading and encapsulation efficiency of rifampicin, and reduce the burst release in the process of rifampicin release.