Sivakumar, R (2017) Optimization of Dual Crosslinked Chitosan Succinate Encrusted Biodegradable Polymeric Beads: Applications to Targeted Drug Delivery. Masters thesis, C. L. Baid Metha College of Pharmacy, Chennai.
|
Text
260102717sivakumar.pdf Download (2MB) | Preview |
Abstract
INTRODUCTION : Targeted drug delivery is a kind of smart drug delivery system which is miraculous in delivering the drug to a patient. This conventional drug delivery system is done by the absorption of the drug across a biological membrane, whereas the targeted release system is that drug is released in a dosage form AIM AND OBJECTIVE: Colorectal cancer is the third most commonly diagnosed malignancy and the fourth leading cause of cancer-related deaths in the world. The global burden of colorectal cancer is expected to increase by 60% to more than 2.2 million new cases and 1.1 million deaths by 2030. Rapid increases in both CRC incidence and mortality are now observed in many countries particularly in Europe, Asia and South America. Capecitabine drug has been widely used for treating colon cancer but it‟s very short plasma half- life (0.85 hours) leads to its rapid elimination from the body necessitating its frequent administration. The oral colon targeting system refers to the system, in which the release of orally administered therapeutic agents is controlled, until they reach cecum or colon. Hence the local action can be exerted into the diseased region devoiding destructing the normal cells of upper GIT. This approach facilitates the therapeutic efficacy of the drug by minimizing the toxic or adverse effect at the same time. Most of the conventional drug delivery systems targeting colon fails, as the therapeutic agent don‟t reach up to the colon in appropriate concentration. This effective and safe therapy aspiring colon specific delivery is of almost challenging task. During past few decades, employing natural polymers for the development of various drug delivery systems has been time lighted. Natural polymers have ample of advantages like easy availability, cost effectiveness, biodegradability and biocompatibility. Alginates are generally regarded as safe (GRAS) by the FDA. Na-Alg is a Na salt of alginic acid, which is a co-polymer of 1. -D-alginic acid, which is a co-polymer of 2. -D-mannuronic acid (m) and α- L-gluuronic acid (G) having 1,4-glycosidic linkage between them. Many authors were reported that calcium alginate beads have been used for oral control drug delivery system but it has a main drawback of pH dependent solubility which could lead to fast dissolution rate and rapid drug release in gastro intestinal fluid and it also shows poor entrapment efficiency due to its poor viscosity. In recent year‟s blended polymeric system are exploited in the region of targeted drug delivery systems. Biodegradable polymers obtained from Tamarindus indica L. seeds received the consideration of several researches because of its economic and easy availability. TSP is composed of chemically highly branched carbohydrate polymer. Its backbone consists of D-glucose units joined with (1-4) b-linkages similar to that of cellulose. It consists of a main chain of b-D- (1-4)-galactopyranosyl unit with a side chain of single xylopyranosyl unit attached to every second, third and fourth of D glucopyranosyl unit through a-D- (1-6) linkage. Earlier report was shown while increasing the ratio of the TSP the drug loading was found to be maximum might be due to increase in viscosity of the polymerblend solutions and could prevent the drug leakage from the beads. The objective of the study was to develop colon specific drug delivery system (CDDS) which is capable of protecting the drug en route to the colon i.e. drug release and absorption should not occur in the stomach as well as the small intestine but only released and absorbed once the system reaches the colon. Cross-linked Chitosan succinate was reported as pH dependent polymer which was most suitable polymer for colon specific delivery system and protected acid degradation of capecitabine in acidic pH. To our best knowledge still no reports were available for the study of chitosan succinate cross-linked CP loaded AG-TG beads as a novel colon targeted drug delivery system. CONCLUSION: The micro beads of capecitabine were formulated and optimized using Box – Behnken model. The quantitative responses of in vitro drug release for different combinations of independent variables, sodium alginate as release retarding polymer, Tamarind gum as acid resistant polymer and calcium chloride as cross-linking agent were obtained experimentally, and the results were found to fit the design model. The drug entrapment efficiency of the beads was increased while increasing concentration of tamarind gum. The quantitative effect of these factors at different levels on the responses could be predicted using polynomial equations, and high linearity was observed between predicted and actual values of response variables. The results of release studies indicate that chitosan succinate coated tamarind beads offer a high degree of protection from premature drug release in simulated upper GIT conditions. Chitosan Succinate coated tamarind beads deliver most of the drug load in the colon, an environment rich in bacterial enzymes that degrade the chitosan succinate and allow drug release to occur at the desired site. Thus, dual cross-linked CS decorated alg/tamarind beads may potential system for colon delivery of capecitabine for chemotherapy of cancer.
| Item Type: | Thesis (Masters) |
|---|---|
| Additional Information: | Reg.No.261510012 |
| Uncontrolled Keywords: | Optimization ; Dual Crosslinked Chitosan Succinate Encrusted ; Biodegradable Polymeric Beads ; Targeted Drug Delivery |
| Subjects: | PHARMACY > Pharmaceutics |
| Depositing User: | Ravindran C |
| Date Deposited: | 23 Mar 2018 06:30 |
| Last Modified: | 23 Mar 2018 06:30 |
| URI: | http://repository-tnmgrmu.ac.in/id/eprint/6467 |
Actions (login required)
 |
View Item |
