doi:10.1038/nindia.2012.173 Published online 26 November 2012
Researchers have developed a new type of drug-delivering film using xyloglucan, a polysaccharide isolated from the kernels of tamarind seeds. The film has shown faster release of rizatriptan benzoate (RB), a drug used to treat migraine, through the buccal mucosa, the lining inside the mouth.
This tamarind seed-derived polysaccharide could yield a new biocompatible and non-toxic drug carrier to alleviate symptoms of migraine.
Buccal mucosa is rich in blood vessels, allowing faster uptake of drug into the bloodstream and thus rapid action of the drug. This led researchers to design various buccal drug-delivery systems such as tablets, wafers, gels and films. However, there is a dearth of mucoadhesive buccal films made from natural compounds and offering better patient compliance.
To prepare smarter biocompatible and biodegradable buccal films, the researchers synthesised the RB-loaded bilayer buccal films using tamarind seed xyloglucan (TSX), carbopol, a polymer and glycerin. They prepared nine types of films, varying the concentrations of TSX and glycerin. The films' ability to release drugs, permeate and adhere to buccal mucosa was investigated using pig buccal mucosa.
The film containing 4 per cent TSX and 8 per cent glycerin showed highest drug release in 2 hours. Swelling and bioadhesion are two essential properties for a good buccal drug-delivery system. Bioadhesive force was found to increase with higher concentrations of TSX, ensuring better delivery of drug at the application site.
TSX at 4 per cent and 6 per cent showed good swelling properties with greater hydration rates and increased porosity yielding good drug release. This is encouraging, as good swelling is linked to better bioadhesion.
The researchers say that cheap and abundantly available natural polysaccharide TSX could offer a promising drug carrier for delivery of soluble drugs like RB through the buccal route.