Design and evaluation of matrix-based controlled release tablets of diclofenac sodium and chondroitin sulphate

Abstract

The purpose of the present study was to develop and characterize an oral controlled release drug delivery system for concomitant administration of diclofenac sodium (DS) and chondroitin sulfate (CS). A hydrophilic matrix-based tablet using different concentrations of hydroxypropylmethylcellulose (HPMC) was developed using wet granulation technique to contain 100 mg of DS and 400 mg of CS. Formulations prepared were evaluated for the release of DS and CS over a period of 9 hours in pH 6.8 phosphate buffer using United States Pharmacopeia (USP) type II dissolution apparatus. Along with usual physical properties, the dynamics of water uptake and erosion degree of tablet were also investigated. The in vitro drug release study revealed that HPMC K100CR at a concentration of 40% of the dosage form weight was able to control the simultaneous release of both DS and CS for 9 hours. The release of DS matched with the marketed CR tablet of DS with similarity factor (f 2 ) above 50. Water uptake and erosion study of tablets indicated that swelling followed by erosion could be the mechanism of drug release. The in vitro release data of CS and DS followed KorsmeyerPeppas and zero-order kinetics, respectively. In conclusion, the in vitro release profile and the mathematical models indicate that release of CS and DS can be effectively controlled from a single tablet using HPMC matrix system.

Coated minispheres of salmon calcitonin target rat intestinal regions to achieve systemic bioavailability: Comparison between intestinal instillation and oral gavage

“…The rate of drug release in this model is controlled by the velocity and position of the front dividing the glassy and rubbery portion of the polymer. Various drug delivery system can be modelled with Korsmeyer-Peppas kinetic model, for example the release of chondroitin sulphate from the hydrophilic HPMC tablets [41], and theophylline released from wax matrix granules [42]. Overall, the Korsmeyer-Peppas model suggests that biological fluids induce swelling of coating layers and gelatin, channels are formed, which allow sCT to be released from minispheres.…”

Comparison Between the Effect of Strongly and Weakly Cationic Exchange Resins on Matrix Physical Properties and the Controlled Release of Diphenhydramine Hydrochloride from Matrices

“…According to the resultant kinetic parameters (Table I), all release profiles were satisfactorily fitted to the power law equation using appropriate n values (R 2 ≥0.98). The value of n from the free-resin matrices was 0.569, indicating an anomalous transport corresponding to drug diffusion in the hydrated matrix and the polymer erosion (22,23). However, the matrices containing either resin exhibited a trend of decreasing n values, i.e., from 0.569 to 0.227 for Dow88 and from 0.569 to 0.410 for Am64, Fig.…”

<i>In Vitro</i> Evaluation of Mucoadhesive Vaginal Tablets of Antifungal Drugs Prepared with Thiolated Polymer and Development of a New Dissolution Technique for Vaginal Formulations

“…This result confirms that the release of EN and MN tablets prepared with PAA-Cys were similar to each other. 19) In addition, the similarity factor between PAA tablets was found to be 68.180. The similarity study results confirmed that the presence of EN or MN did not affect the release profile of the drug from the formulations.…”