Optimization of ranitidine hydrochloride based on stability performance in directly compressible immediate and sustained release formulations.

Ranitidine hydrochloride (RTD), a moisture-sensitive drug, has issues of stability during shelf life especially when formulated through wet granulation method. In current study, RTD was blended with non-hygroscopic excipient like ethyl cellulose and compressed using direct compression method. The physical and physicochemical characteristics were evaluated including hardness, thickness, diameter, friability, weight variation, disintegration, dissolution and accelerated stability study to optimize findings. Subsequently, the optimized formulation was characterized for Fourier Transform Infrared (FTIR) analysis and in vitro drug release kinetics. The physical characterization was unaffected by polymer variation while the friability and weight variation were within the USP limits. In vitro drug release depicted that the release rate was sustained by increasing the amount of ethyl cellulose, with a 10% increase of ethyl cellulose 99.09% drug was released. FTIR analysis exhibited no interaction among the ingredients of the optimized formulation (E2). The optimized formulation followed Hixson-Crowell release kinetics. Formulation A5 displayed immediate release characters as plain uncoated formulation. Accelerated studies showed no significant change in the drug content. The RTD was successfully sustained to be released up to 6 h and accelerated stability showed that the optimized formulation (E2) containing 4% starch 1500 and 10% of ethyl cellulose, respectively, was stable up to 6 months.

Hansen parameter evaluation for the characterization of titania photocatalysts using particle size distributions and combinatorics.

Titania photocatalysts have great potential as remediators of air pollution. Although various aspects of photocatalyst synthesis, adsorption and photoactivity have been investigated, a thorough understanding of the particle surface behavior has not yet been fully realized. In order to learn more about the principles behind the surface behavior, we investigate the Hansen solubility/similarity parameters (HSPs) for analyzing and evaluating three photocatalysts synthesized by the gas phase method, solvothermal reaction and sol-gel method, respectively. A particle size distribution-based categorization scheme is introduced for characterizing each material's Hansen parameters based on its interaction with a list of selected probe liquids. The latter was deduced from particle size distributions assessed by analytical centrifugation. Subsequent comparison of the Hansen parameters of the investigated materials shows how HSPs can potentially be used as a model for predicting the pollutant adsorption behavior on the photocatalyst surface. This serves as a first step in heading towards an improved understanding of the particle behavior and translating it into a knowledge-based design, i.e., synthesis and hybridization of novel photocatalysts.