Factors a!ecting the degradation rate of poly(lactide-co-glycolide) microspheres in vivo and in vitro
- نوع فایل : کتاب
- زبان : انگلیسی
- مؤلف : M.A. Tracy*, K.L. Ward, L. Firouzabadian, Y. Wang, N. Dong, R. Qian, Y. Zhang
- چاپ و سال / کشور: 1999
Description
The purpose of this work was to study the degradation of poly(lactide-co-glycolide) (PLG) microspheres in vivo and in vitro. Degradation rate constants were determined by measuring the polymer molecular weight as a function of time by gel-permeation chromatography. The e!ects of PLG chemistry and the e!ects of encapsulating the sparingly soluble salt zinc carbonate and the protein recombinant human growth hormone (rhGH) on the degradation rate were assessed. It was found that in vivo degradation was faster than in vitro degradation. In addition, di!erent types of PLGs were found to degrade at di!erent rates depending on the chemistry of the polymer end group and, to a lesser extent, the molecular weight. Finally, zinc carbonate was found to retard the degradation of some PLGs. These degradation studies have proved valuable in the design of sustained release microsphere products. ( 1999 Elsevier Science Ltd. All rights reserved
Biomaterials 20 (1999) 1057-1062 Received 20 January 1998; accepted 30 December 1998
