Autor(es):
Brunner, Cornelia T. 
; Baran, E. T. ; Pinho, Elisabete D. ; Reis, R. L. ; Neves, N. M.
Data: 2011
Identificador Persistente: http://hdl.handle.net/1822/14234
Origem: RepositóriUM - Universidade do Minho
Descrição
Poly(butylene succinate) (PBSu), poly(butylene succinate-co-adipate) (PBSA) and poly(butylene
terephthalate-co-adipate) (PBTA) microcapsules were prepared by the double emulsion/solvent evaporation
method. The effect of polymer and poly(vinyl alcohol) (PVA) concentration on the microcapsule
morphologies, drug encapsulation efficiency (EE) and drug loading (DL) of bovine serum albumin (BSA)
and all-trans retinoic acid (atRA) were all investigated. As a result, the sizes of PBSu, PBSA and PBTA
microcapsules were increased significantly by varying polymer concentrations from 6 to 9%. atRA was
encapsulated into the microcapsules with an high level of approximately 95% EE. The highest EE and DL
of BSA were observed at 1% polymer concentration in values of 60 and 37%, respectively. 4% PVA was
found as the optimum concentration and resulted in 75% EE and 14% DL of BSA. The BSA release from
the capsules of PBSA was the longest, with 10% release in the first day and a steady release of 17% until
the end of day 28. The release of atRA from PBSu microcapsules showed a zero-order profile for 2 weeks,
keeping a steady release rate during 4 weeks with a 9% cumulative release. Similarly, the PBSA microcapsules
showed a prolonged and a steady release of atRA during 6 weeks with 12% release. In the case
of PBTA microcapsules, after a burst release of 10% in the first day, showed a parabolic release profile of
atRA during 42 days, releasing 36% of atRA.
