Pulsatile protein release from monodisperse liquid-core microcapsules of controllable shell thickness.
OBJECTIVE
Pulsatile delivery of proteins, in which release occurs over a short time after a period of little or no release, is desirable for many applications. This paper investigates the effect of biodegradable polymer shell thickness on pulsatile protein release from biodegradable polymer microcapsules.


METHODS
Using precision particle fabrication (PPF) technology, monodisperse microcapsules were fabricated encapsulating bovine serum albumin (BSA) in a liquid core surrounded by a drug-free poly(lactide-co-glycolide) (PLG) shell of uniform, controlled thickness from 14 to 19 μm.


RESULTS
When using high molecular weight PLG (Mw 88 kDa), microparticles exhibited the desired core-shell structure with high BSA loading and encapsulation efficiency (55-65%). These particles exhibited very slow release of BSA for several weeks followed by rapid release of 80-90% of the encapsulated BSA within 7 days. Importantly, with increasing shell thickness the starting time of the pulsatile release could be controlled from 25 to 35 days.


CONCLUSIONS
Biodegradable polymer microcapsules with precisely controlled shell thickness provide pulsatile release with enhanced control of release profiles.
Department of Chemical and Biomolecular Engineering, University of Illinois, 600 S. Mathews Avenue, Urbana, Illinois, 61801, USA.
Yujie
Y
Xia
Daniel W
DW
Pack
D063566:Biodegradable Plastics / Q000737:chemistry; D002214:Capsules / Q000737:chemistry*; D004339:Drug Compounding / Q000379:methods; D008970:Molecular Weight; D010316:Particle Size; D011098:Polyglactin 910 / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry; D011506:Proteins / Q000737:chemistry*; D012710:Serum Albumin, Bovine / Q000737:chemistry
D063566:Biodegradable Plastics; D002214:Capsules; D011108:Polymers; D011506:Proteins; D012710:Serum Albumin, Bovine; D011098:Polyglactin 910