Erosion Induced Controllable Release of Gliclazide Encapsulated Inside Degradable Polymeric Particles

• Published in: Macromolecular bioscience Vol. 4; no. 3; pp. 308 - 313
• Main Authors: Zhao, Yue, Chen, Wenna, Cai, Qing, Wang, Shenguo, Bo, Jun, Wu, Chi
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Weinheim WILEY-VCH Verlag 15.03.2004; WILEY‐VCH Verlag; Wiley-VCH
• Subjects: Applied sciences; Biodegradation, Environmental; Biological and medical sciences; Capsules; colloids; controllable drug releasing; Delayed-Action Preparations - chemistry; Drug Carriers - chemistry; Drug Carriers - metabolism; Epoxy Compounds - chemistry; Exact sciences and technology; Forms of application and semi-finished materials; General pharmacology; Gliclazide - administration & dosage; Gliclazide - chemistry; Hydrogen-Ion Concentration; Hypoglycemic Agents - administration & dosage; Hypoglycemic Agents - chemistry; light scattering; Medical sciences; micronization; Miscellaneous; Pharmaceutical technology. Pharmaceutical industry; Pharmacology. Drug treatments; polyesters; Polyesters - chemistry; Polyesters - metabolism; Polyglactin 910 - chemistry; Polymer industry, paints, wood; Technology of polymers; Glycolic acid copolymer; Nanoparticle; Control release polymer; Lactic acid copolymer; Drug carrier; Phase reversal; Ethylene oxide copolymer; Experimental study; Random copolymer; Triblock copolymer; Particle size distribution; Hypoglycemic agent; Lactic acid polymer; Aqueous medium; Gliclazide; pH; Kinetics; Manufacturing; Release; Growth from solution; Aliphatic copolymer
• ISSN: 1616-5187; 1616-5195
• DOI: 10.1002/mabi.200300061

The microphase inversion of water‐insoluble poly(L‐lactide), “poly[(L‐lactide)‐co‐glycolide] and polylactide‐block‐poly(ethylene oxide)‐block‐polylactide from THF to water can result in narrowly distributed stable particles. Gliclazide, a commercial drug, can be encapsulated inside during the process. The formation and degradation of such particles was studied by laser light scattering. In comparison with the corrosion of a bulk material, the degradation of each particle is so fast that we only detect the decrease of the particle number, not the corrosion of individual particles. Therefore, the degradation is a “one‐by‐one” random process, just like the chemical reaction of molecules in solution. The disappearing rate of the particle number is nearly independent of time, ideal for the controlled release of drugs encapsulated inside. The amount of encapsulated gliclazide depends on the copolymer's hydrophobicity (composition), while the releasing rate mainly is, directly related to the disappearing rate of the particles. The correlation between the fluorescence intensity and the degradation was used to study the kinetics of gliclazide releasing. The releasing pattern is controllable with a proper choice of the drug loading, copolymer composition, pH and temperature.