Evaluation of a Poly (Acrylic) Acid Polymer as a Sustained Release Matrix for Ciprofloxacin Hydrochloride

Abstract

An evaluation of the sustained release (SR) properties of a polyacrylic acid polymer, Carbopol 971(CP 971) as matrix in the formulation of ciprofloxacin hydrochloride (CH) tablets was carried out. The CP 971 in concentrations of up to 40 % w/w were wet granulated using ethanol 95% v/v and the dried granules were evaluated for packing, densification and flow properties. The tablets were evaluated for hardness, friability, uniformity of weight and content of active ingredient. The formulations dissolution profiles were tested in 0.1 N Hydrochloric acid (0.1 N HCl, pH 1.3), simulated gastric fluid (SGF, pH 1.2) and simulated intestinal fluid (SIF, pH 7.2) without enzymes. Results obtained showed significant retardation (p < 0.05) of ciprofloxacin release as the polymer concentration increased. Drug release was significantly different in the three media used with the release rate being faster in SGF than 0.1 N HCl and SIF. This can be attributed to the high solubility of the drug in acidic media. More than 50% of drug content was released within 4 h. Ciprofloxacin tablets containing 20 % w/w was adjudged the best formulation and drug release from the formulation was diffusion controlled (Fickian).