TY - JOUR
T1 - Release of prednisolone and inulin from a new calcium-alginate chitosan-coated matrix system for colonic delivery
AU - Araujo, Valeria
AU - Gamboa, Alexander
AU - Caro, Nelson
AU - Abugoch, Lilian
AU - Gotteland, Martin
AU - Valenzuela, Fernando
AU - Merchant, Hamid A
AU - Basit, Abdul W
AU - Tapia, Cristián
N1 - Copyright © 2013 Wiley Periodicals, Inc.
PY - 2013/8
Y1 - 2013/8
N2 - Putative colonic release formulations of calcium (Ca)-alginate coated with chitosan containing two different actives, prednisolone and inulin, were prepared in three different sizes, beads (D50 = 2104 μm) and microparticles (D50 = 354 and 136 μm). The formulations were tested in standard phosphate buffer and biorelevant Krebs bicarbonate buffer at pH 7.4, and were further evaluated in the presence of the bacterium E. coli. Product yield and encapsulation were higher with prednisolone than with inulin. In Krebs bicarbonate buffer, a clear relationship between particle size and prednisolone release was observed. In contrast, release of inulin was independent of the particle size. In phosphate buffer, the particles eroded quickly, whereas in Krebs buffer, the particles swelled slowly. The difference in behavior can be attributed to the formation of calcium phosphate in the phosphate buffer medium, which in turn weakens the Ca-alginate matrix core. In the presence of E. coli, the formulations were fermented and the release of prednisolone was accelerated. In conclusion, the buffer media affects formulation behavior and drug release, with the bicarbonate media providing a better simulation of in vivo behavior. Moreover, the susceptibility of the formulations to bacterial action indicates their suitability as carriers for colonic drug delivery.
AB - Putative colonic release formulations of calcium (Ca)-alginate coated with chitosan containing two different actives, prednisolone and inulin, were prepared in three different sizes, beads (D50 = 2104 μm) and microparticles (D50 = 354 and 136 μm). The formulations were tested in standard phosphate buffer and biorelevant Krebs bicarbonate buffer at pH 7.4, and were further evaluated in the presence of the bacterium E. coli. Product yield and encapsulation were higher with prednisolone than with inulin. In Krebs bicarbonate buffer, a clear relationship between particle size and prednisolone release was observed. In contrast, release of inulin was independent of the particle size. In phosphate buffer, the particles eroded quickly, whereas in Krebs buffer, the particles swelled slowly. The difference in behavior can be attributed to the formation of calcium phosphate in the phosphate buffer medium, which in turn weakens the Ca-alginate matrix core. In the presence of E. coli, the formulations were fermented and the release of prednisolone was accelerated. In conclusion, the buffer media affects formulation behavior and drug release, with the bicarbonate media providing a better simulation of in vivo behavior. Moreover, the susceptibility of the formulations to bacterial action indicates their suitability as carriers for colonic drug delivery.
KW - Alginates/chemistry
KW - Anti-Inflammatory Agents/administration & dosage
KW - Chitosan/analogs & derivatives
KW - Colon/metabolism
KW - Drug Carriers/chemistry
KW - Escherichia coli/physiology
KW - Glucuronic Acid/chemistry
KW - Hexuronic Acids/chemistry
KW - Humans
KW - Hydrogels/chemistry
KW - Inulin/administration & dosage
KW - Particle Size
KW - Prednisolone/administration & dosage
U2 - 10.1002/jps.23656
DO - 10.1002/jps.23656
M3 - Article
C2 - 23839971
VL - 102
SP - 2748
EP - 2759
JO - Journal of Pharmaceutical Sciences
JF - Journal of Pharmaceutical Sciences
SN - 0022-3549
IS - 8
ER -