11.3.3 Colon Drug Delivery
Orally administered colon-targeted drugs are expected to protect the therapeutic
agent release and degradation in the stomach as well as in the small intestine and
able to deliver it in colon. However, the acidic environment of upper gastrointestinal tract induces the degradation of drugs. This obstacle has been addressed by
designing drug delivery system that facilitates the release of therapeutic agent in
neutral pH. But the difference in the pH of intestine (7.4) and colon (6.8) region
adversely affected the ability of pH-dependent drug delivery system to deliver the
drug to the colonic region. In order to overcome this pH associated issue, drug
encapsulated with polysaccharides offers advantages due to their stability in
divergent pH conditions (Park et al. 2010). Natural polysaccharides found to be
alternative candidates for the fabrication of colon specific drug delivery systems as
colonic bacteria able to degrade them effectively (McConnell et al. 2008). Inter
polymer complexes composed of chitosan and carboxymethyl fenugreek gum with
tamoxifen was fabricated by Randhawa et al. Drug coated with polymeric system
were able to protect the release of bioactive compound in stomach as well as in
small intestine, and in the presence of rat cecal content 91% of tamoxifen released
was observed from in vitro and in vivo experiments (Randhawa et al. 2012).
Easy availability, low cost, cytocompatibility and mucoadhesive nature of
fenugreek gum make it as a gold standard natural polymer-based excipient for colon
specific drug delivery. But research involving fenugreek gum based excipients for
colon drug delivery is still in nascent stage, and therefore pressure controlled colon
specific capsules and osmotic controlled drug delivery can be developed using
fenugreek gum. These colon specific drug delivery systems can be evaluated by
mimicking various pH conditions of gastric fluid, jejunum, small intestine and
ileum. The efficacy of drug delivery system could be observed by incubating it with
buffer medium containing ezypectinase and dextranase. Numerous animal models
involving dog, guinea pigs and rats can be designed to evaluate the activity of
formulation in complex cellular conditions. The absorption and distributional
behaviour of fenugreek-based drug delivery system can be evaluated using gamma
scintigraphy and high frequency techniques.
11.3.4 Vaginal Drug Delivery
Self-cleansing property of vaginal tract has always been a problem for the establishment of drug in the area of infection. Dynamic vaginal delivery system is
expected to deliver the therapeutic agents to the site of infection or injury for a
longer time span (Pavelić et al. 2001). Vaginal films comprising of polymers loaded
with bioactive agents proved to be the best candidate as it offers stability, ease of
administration and longer retention (Garg et al. 2005). Bioadhesiveness and biocompatibility of natural polymers draw interest of researchers for their application
11 Pharmaceutical and Therapeutic Applications of Fenugreek Gum
389
Orally administered colon-targeted drugs are expected to protect the therapeutic
agent release and degradation in the stomach as well as in the small intestine and
able to deliver it in colon. However, the acidic environment of upper gastrointestinal tract induces the degradation of drugs. This obstacle has been addressed by
designing drug delivery system that facilitates the release of therapeutic agent in
neutral pH. But the difference in the pH of intestine (7.4) and colon (6.8) region
adversely affected the ability of pH-dependent drug delivery system to deliver the
drug to the colonic region. In order to overcome this pH associated issue, drug
encapsulated with polysaccharides offers advantages due to their stability in
divergent pH conditions (Park et al. 2010). Natural polysaccharides found to be
alternative candidates for the fabrication of colon specific drug delivery systems as
colonic bacteria able to degrade them effectively (McConnell et al. 2008). Inter
polymer complexes composed of chitosan and carboxymethyl fenugreek gum with
tamoxifen was fabricated by Randhawa et al. Drug coated with polymeric system
were able to protect the release of bioactive compound in stomach as well as in
small intestine, and in the presence of rat cecal content 91% of tamoxifen released
was observed from in vitro and in vivo experiments (Randhawa et al. 2012).
Easy availability, low cost, cytocompatibility and mucoadhesive nature of
fenugreek gum make it as a gold standard natural polymer-based excipient for colon
specific drug delivery. But research involving fenugreek gum based excipients for
colon drug delivery is still in nascent stage, and therefore pressure controlled colon
specific capsules and osmotic controlled drug delivery can be developed using
fenugreek gum. These colon specific drug delivery systems can be evaluated by
mimicking various pH conditions of gastric fluid, jejunum, small intestine and
ileum. The efficacy of drug delivery system could be observed by incubating it with
buffer medium containing ezypectinase and dextranase. Numerous animal models
involving dog, guinea pigs and rats can be designed to evaluate the activity of
formulation in complex cellular conditions. The absorption and distributional
behaviour of fenugreek-based drug delivery system can be evaluated using gamma
scintigraphy and high frequency techniques.
11.3.4 Vaginal Drug Delivery
Self-cleansing property of vaginal tract has always been a problem for the establishment of drug in the area of infection. Dynamic vaginal delivery system is
expected to deliver the therapeutic agents to the site of infection or injury for a
longer time span (Pavelić et al. 2001). Vaginal films comprising of polymers loaded
with bioactive agents proved to be the best candidate as it offers stability, ease of
administration and longer retention (Garg et al. 2005). Bioadhesiveness and biocompatibility of natural polymers draw interest of researchers for their application
11 Pharmaceutical and Therapeutic Applications of Fenugreek Gum
389