title: PLGA microspheres with high drug loading and high encapsulation efficiency prepared by a novel solvent evaporation technique.
abstract: PLGA microspheres with high drug loading and high encapsulation efficiency were fabricated by a novel solvent evaporation process-in-situ S/O/W process. Insulin was dissolved in DMSO and dispersed into DCM to form fine particles due to an anti-solvent effect. The in-situ formed suspension was then added into an aqueous phase and emulsified. Microspheres were formed following the evaporation of organic solvents. The experimental results showed that the modified S/O/W process could encapsulate more than 90%(w/w) insulin in the microspheres with a drug loading of over 15% and the initial burst was much less than microspheres made by a W1/O/W2 process. Compared with a traditional water-in-oil-in-water (W1/O/W2) process, the in-situ S/O/W process does not require high solubility of the encapsulated drug in water and, because no special pre-treatment is needed to reduce the particle size of the drug, it is superior to an ordinary S/O/W process. The in-situ S/O/W process is particularly applicable to encapsulate peptides and low molecular weight proteins.
authors.affiliation: School of Life Science and Technology, Shanghai Jiaotong University, China.
authors.forename: Wenchao
authors.initials: W
authors.lastname: Bao
authors.forename: Jiaxiang
authors.initials: J
authors.lastname: Zhou
authors.forename: Jiufu
authors.initials: J
authors.lastname: Luo
authors.forename: Dengxi
authors.initials: D
authors.lastname: Wu
mesh_terms: D000818:Animals; D001672:Biocompatible Materials / Q000737:chemistry; D003692:Delayed-Action Preparations / Q000737:chemistry; D004121:Dimethyl Sulfoxide / Q000737:chemistry; D004339:Drug Compounding / Q000379:methods; D007328:Insulin; D019344:Lactic Acid / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D008863:Microspheres; D010316:Particle Size; D011100:Polyglycolic Acid / Q000737:chemistry*; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011108:Polymers / Q000737:chemistry*; D012997:Solvents / Q000737:chemistry; D013499:Surface Properties; D013552:Swine
chemical_list: D001672:Biocompatible Materials; D003692:Delayed-Action Preparations; D007328:Insulin; D011108:Polymers; D012997:Solvents; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; D004121:Dimethyl Sulfoxide