Fabrication of microspheres using blends of poly(ethylene adipate) and poly(ethylene adipate)/poly(hydroxybutyrate-hydroxyvalerate) with poly(caprolactone): incorporation and release of bovine serum albumin.
Spherical microspheres composed of polymer blends 80:20 PEAD/PCL II and 40:40:20 PEAD/P(HB-HV)/PCL II containing a range of BSA loadings have been fabricated using a single emulsion technique with solvent evaporation. 80:20 PEAD/PCL II microspheres had smooth surfaces while 40:40:20 PEAD/P(HB-HV)/PCL II microspheres consisted of a mixture of smooth surfaced, microporous and macroporous microsphere fractions. Irrespective of fabrication polymer, microspheres were produced in high yield (> 75%) and BSA incorporation had no significant effect on microsphere size distribution which ranged from 0.6 to 5 microns and from 2.1 to 50 microns for 80:20 PEAD/PCL II and 40:40:20 PEAD/P(HB-HV)/PCL II microspheres, respectively. The loss of BSA by partitioning into the aqueous phase resulted in low encapsulation efficiencies (< 14.5%). BSA release increased significantly with the-oretical percentage loading but the relationship could not be confirmed when the total cumulative release of BSA was expressed as a percentage of the actual total BSA incorporated. Significant BSA release could be detected for up to 26 days.
Atkins
T W
TW
Department of Pharmaceutical and Biological Sciences, Aston University, Birmingham, UK.
D000818:Animals; D002021:Buffers; D002417:Cattle; D016503:Drug Delivery Systems; D004655:Emulsions; D008855:Microscopy, Electron, Scanning; D008863:Microspheres; D010316:Particle Size; D011091:Polyesters / Q000737:chemistry*; D016062:Porosity; D012710:Serum Albumin, Bovine / Q000737:chemistry*; D013499:Surface Properties; D000094122:Polyhydroxybutyrates
D002021:Buffers; D004655:Emulsions; D011091:Polyesters; D012710:Serum Albumin, Bovine; C052620:poly(3-hydroxybutyrate)-co-(3-hydroxyvalerate); D000094122:Polyhydroxybutyrates; C016240:polycaprolactone