In this report, efforts have been made to develop isoniazid loaded chitosan-montmorillonite nanoparticles by ionic gelation of chitosan with pentasodium tripolyphosphate. The nanoparticles have been characterized by FTIR, XRD, SEM and TEM. The effect of surfactant and particle size on chitosan nanoparticles have been assessed with regard to swelling, encapsulation efficiency and release of isoniazid in different mediums. Swelling experiments provide important information on drug diffusion properties, which indicates that the chitosan nanoparticles are highly sensitive to the pH environment. The drug release mechanism has been studied during different time periods using a UV-visible spectrophotometer. Cytotoxicity has been assessed by MTT assay analysis. Mucoadhesion properties have been appraised by an in vitro wash off test and an ex vivo mucoadhesion test. The results imply that chitosan-montmorillonite nanoparticles can be exploited as potential drug carriers for controlled-release applications.

The high polarity of the protoberberine alkaloids present in Coptis teeta has made it difficult to quantify the alkaloids. This study was designed to develop and validate a thin-layer chromatography (TLC) densitometric-based method using high-performance thin-layer chromatography for quantification of berberine. The separation was achieved in a solvent system consisting of butanol:ethyl acetate:formic acid:water by volume on TLC aluminum plate precoated with silica gel 60 F254. Determination and quantification were performed by densitometric scanning under mercury lamp at a wavelength 351 nm in absorbance mode. The validated method gave compact bands for berberine at an Rf of 0.70. The precision, accuracy and reproducibility of the method were validated by following International Conference on Harmonization guidelines. Graphically, linear results were obtained for berberine with correlation coefficient of 0.997 ± 0.09% (R ± SD) in the concentration range of 90-210 ng/band. The limit of quantification and limit of detection from the analysis were found to be 70 and 30 ng/band, respectively. The berberine concentration in the methanol extract of C. teeta was found to be 30.97 ± 0.55 mg in 100 mg of the crude drug. The method developed here in can be implemented in the analysis and routine quality control of herbal materials and formulations containing C. teeta and berberine.