title: Comparison of various injectable protein-loaded biodegradable poly(lactide-co-glycolide) (PLGA) devices: in-situ-formed implant versus in-situ-formed microspheres versus isolated microspheres.
abstract: The purpose of this research was to prepare various injectable, protein (cytochrome c)-loaded biodegradable poly(lactide-co-glycolide) (PLGA) devices by a novel microencapsulation method and to compare their characteristics. Syringeable mixtures of polymer and protein solidified upon injection when coming in contact with water, and formed a solid matrix-type implant or microspheres (in-situ-formed implant or in-situ-formed microspheres, respectively) with cytochrome c entrapped. These devices exhibited different characteristics in terms of in vitro cytochrome c release profile, percentage cytochrome c encapsulation efficiency, and particle size. The burst effect from these devices exhibited the following trend: in-situ-formed implant > in-situ-formed microspheres > isolated microspheres. The in-situ-formed microspheres were larger in size than the isolated microspheres. Also, the isolated microspheres exhibited the slowest release of cytochrome c, whereas the in-situ-formed implant exhibited the fastest release. The microencapsulation process can produce various drug-loaded injectable biodegradable PLGA devices having different characteristics.
authors.affiliation: Department of Applied Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island, Kingston 02881, USA. rjain@elancorp.com
authors.forename: R A
authors.initials: RA
authors.lastname: Jain
authors.forename: C T
authors.initials: CT
authors.lastname: Rhodes
authors.forename: A M
authors.initials: AM
authors.lastname: Railkar
authors.forename: A W
authors.initials: AW
authors.lastname: Malick
authors.forename: N H
authors.initials: NH
authors.lastname: Shah
mesh_terms: D003574:Cytochrome c Group / Q000008:administration & dosage / Q000737:chemistry; D003692:Delayed-Action Preparations; D004337:Drug Carriers; D004339:Drug Compounding; D004343:Drug Implants; D019344:Lactic Acid; D008863:Microspheres; D010316:Particle Size; D011100:Polyglycolic Acid; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011108:Polymers; D011506:Proteins / Q000008:administration & dosage* / Q000737:chemistry
chemical_list: D003574:Cytochrome c Group; D003692:Delayed-Action Preparations; D004337:Drug Carriers; D004343:Drug Implants; D011108:Polymers; D011506:Proteins; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid