Study of the initial stages of drug release from a degradable matrix of poly(d,l-lactide-co-glycolide).
The initial stages of the in vitro degradation of and the drug release from a matrix made of poly(d,l-lactide-co-glycolide) was carried out in a phosphate buffer saline (pH 7.0) medium. It has been observed that substantial matrix degradation occurs at the end of 2 weeks of immersion. The drug release using films of the polymer shows a tri-phasic pattern, unlike the bi-phasic patterns usually seen. Mechanisms are proposed for each phase of release, based on results from weight loss, amount of water absorption and scanning electron microscopy. The details of the structural changes and their effects on drug release may have implications for delivering potent drugs over a 2-week period.
Frank
Alexis
A
School of Materials Engineering, Nanyang Technological University, N4.1-1-30 Nanyang Avenue, 639798 Singapore, Singapore.
Kumar Rath
Santosh
S
Boey
Freddy
F
Venkatraman
Subbu
S
D020341:Absorbable Implants; D000042:Absorption; D001672:Biocompatible Materials / Q000138:chemical synthesis / Q000737:chemistry; D004058:Diffusion; D004337:Drug Carriers / Q000138:chemical synthesis / Q000737:chemistry*; D004343:Drug Implants / Q000138:chemical synthesis / Q000737:chemistry*; D007700:Kinetics; D019344:Lactic Acid / Q000737:chemistry*; D008422:Materials Testing; D008567:Membranes, Artificial; D008787:Metoclopramide / Q000008:administration & dosage / Q000737:chemistry*; D010710:Phosphates / Q000737:chemistry; D011100:Polyglycolic Acid / Q000737:chemistry*; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011108:Polymers / Q000737:chemistry*; D044366:Transition Temperature; D014867:Water / Q000737:chemistry*
D001672:Biocompatible Materials; D004337:Drug Carriers; D004343:Drug Implants; D008567:Membranes, Artificial; D010710:Phosphates; D011108:Polymers; D014867:Water; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; D008787:Metoclopramide