Abstract
Calcium-pectinate (Ca-pectinate) beads have shown immense potential as colon-specific drug carrier. However, Ca-pectinate itself is unable to prevent its swelling/degradation in the upper gastro-intestinal (GI) conditions. Hence, polyethyleneimine (PEI) was added in the cross-linking solution to strengthen the Ca-pectinate network. Resveratrol was used as a model drug due to its promising therapeutic activity towards several colonic diseases. Beads were prepared by varying cross-linking solution pH and other formulation variables. The effects of these formulation variables were investigated on the bead's characteristics. Furthermore, surface morphology, drug–polymer interaction, stability, and in vivo pharmacokinetic study of the optimized formulation were performed. The optimized PEI-modified beads prevented drug release in the upper GI conditions, while released the drug in simulated colonic fluid. Furthermore, in vivo pharmacokinetics studies in rats demonstrated delayed appearance of drug in blood after oral administration. The optimized Ca-pectinate beads demonstrated both in vitro and in vivo colon-specific drug release.
Abbreviations | ||
GI | = | tract: gastro-intestinal tract |
CaCl2 | = | calcium chloride |
Ca-pectinate | = | calcium pectinate |
FTIR | = | Fourier transform infra red |
SEM | = | scanning electron microscopy |
SER | = | swelling-erosion ratio |
EE | = | drug encapsulation efficiency |
L | = | drug loading |
MC | = | moisture content |
WL | = | weight loss during drying |
Ca | = | calcium |
Ca2+ | = | calcium cation |
ER | = | elongation ratio |
RT | = | room temperature |
P: D | = | polymer : drug |
PEI | = | polyethyleneimine |
LM | = | Low-methoxy |
SGF | = | simulated gastric fluid |
SIF | = | simulated intestinal fluid |
SCF | = | simulated colonic fluid |
AUC | = | area under the plasma concentration versus time curve |
F | = | bioavailability |
Cmax | = | maximum plasma concentration |
Tmax | = | time to attain the Cmax |
i.v. | = | intravenous. |
Abbreviations | ||
GI | = | tract: gastro-intestinal tract |
CaCl2 | = | calcium chloride |
Ca-pectinate | = | calcium pectinate |
FTIR | = | Fourier transform infra red |
SEM | = | scanning electron microscopy |
SER | = | swelling-erosion ratio |
EE | = | drug encapsulation efficiency |
L | = | drug loading |
MC | = | moisture content |
WL | = | weight loss during drying |
Ca | = | calcium |
Ca2+ | = | calcium cation |
ER | = | elongation ratio |
RT | = | room temperature |
P: D | = | polymer : drug |
PEI | = | polyethyleneimine |
LM | = | Low-methoxy |
SGF | = | simulated gastric fluid |
SIF | = | simulated intestinal fluid |
SCF | = | simulated colonic fluid |
AUC | = | area under the plasma concentration versus time curve |
F | = | bioavailability |
Cmax | = | maximum plasma concentration |
Tmax | = | time to attain the Cmax |
i.v. | = | intravenous. |
Acknowledgements
This study was supported through a National University of Singapore Academic Research Funds R148-050-068-101 and R148-050-068-133.