A new natural gel of Fagonia indica Burm f. extract for the treatment of burn on rats.

Fagonia indica Burm f. (Mushikka or white spine) is a plant distributed in the deserts of Asia and Africa and reported to be medicinal in the scientific literature as well as in the folk medicine. Earlier investigations, the authors isolated a number of bioactive constituents from the plant including flavonoids, sterols and tritepenoids; In addition its flavonoidal content was found remarkably high reaching 3% (calculated as flavonol on dry weight). The present study is an attempt to formulate, characterize and evaluate a natural wound-healing gel preparation containing the crude plant extract. Three formulae (F1-F3) were prepared. The gel properties such as viscosity, swelling ratio, bio-adhesion, in vitro release, stability, microbiological studies, in vivo burn healing test on rats and histopathological features were assessed. The results of the in vitro evaluation and stability studies showed that F3 (0.5% (w/w) of plant extract in 4% (w/w) chitosan) was significantly (p<0.05) the superior compared to other formulations. Besides, from the in vivo burn healing and histological results, F3 enhanced the skin wound re-epithelialization and speed up the healing process compared to the conventional commercial product. Thus, the Fagonia extract loaded chitosan topical gel would be used successfully in burn wound care.

Impact of chitosan as a disintegrant on the bioavailability of furosemide tablets: in vitro evaluation and in vivo simulation of novel formulations.

To determine the effect of chitosan, starch powder, polyvinylpyrrolidone (PVP), Avicel PH 101 powder, Avicel PH 102 granules as a function of different concentrations on the solubility, disintegration and hence dissolution of furosemide from immediate release tablet dosage forms. The tablets were prepared by the wet granulation method and evaluated for hardness, friability, disintegration and in vitro dissolution. Chitosan 7% w/w showed the fastest disintegration of furosemide tablets among the other disintegrants studied. This was attributed to its highest swelling properties and velocity constant of water uptake. The step of adding chitosan during tablet preparation had a great effect on the physical properties and dissolution profiles of the prepared tablets with external addition of chitosan showed best results compared to best results comparing to internal-external or internal addition. The most appropriate force of compression was 4ton/cm(2). The selected formula F15 containing 7% w/w chitosan was successful and showed a high significant (p<0.001) enhancement in disintegration and dissolution behaviors of furosemide tablets in comparison with the commercially available Furosemide ® tablets. These results were supported by the simulated data where F15 formula showed the highest plasma concentration C-max 1.89mcg/mL after 0.5 hr compared to C-max 1.05mcg/mL after 1hr for the reference. The present study demonstrated that chitosan is a very good candidate to be used as a tablet disintegrant and was able to enhance the dissolution of poorly absorbable drugs.