Assessment of in vitro Quality Tests of Paracetamol Brands 500mg in Karachi, Pakistan

Objective: The main purpose of this study is to perform the quality assessment of three different brands of Paracetamol tablets (500 mg) available in local market of Karachi, Pakistan.

Methodology: Several pharmacopeial and non-pharmacopeial tests were applied on selected brands coded as P1, P2 and P3, respectively. A sample of (n = 20) tablets from each coded brand were subjected to pharmacopeial tests such as weight variation, friability, disintegration, assay and dissolution and non- pharmacopeial tests such as hardness, diameter and thickness. Dissolution data were subjected to model dependent and model independent kinetic approaches using Dissolution Data solver.

Results: The Average weight in mg, hardness in kg , thickness and diameter in mm of (n=20) tablets of brands P1, P2, and P3 were noted and their standard deviation were calculated which were found to be 520.625mg (± 0.49 mg), 519.53 mg (± 0.472 mg) and 521.20 mg (±0.494mg),7.25(±0.45kg), 7.48(±0.29kg) and 6.64(±0.11kg), 4.3(±0.15mm), 3.2(±0.15mm), 3.2(±0.11mm) and 12.2(±0.13mm), 12.4(±0.14mm) and 12.6(±0.15mm). Friability of selected brands were found to be 0.37%, 0.41% and 0.26%. Disintegration time were found to be 2minutes26seconds, 2minutes56seconds and 1minute 54 seconds. Percentage Assay of (n=20) tablets of selected brands were found to be as P1= 98.97(± 0.02%), P2= 99.96(± 0.03%) and P3= 99.91(±0.02%). Dissolution were performed at multiple point intervals such as 5 min, 10 min, 20 min, 30 min and 45 min. At 45 minutes the percentage of drug release for P1, P2 and P3 were found to be 98.7%, 99.8% and 98.9%. For the determination of model independent approaches brand P2 were selected as reference formulation. Similarity factor (f2), dissimilarity factor (f1) for brand P1, and P3 were found to be 73.5, 5 and 79.5, 3. All selected brands were subjected to model dependent approaches. In this study all tablets of selected brands P1, P2 and P3 followed First order and weibull model as the r2 values for first order were (0.9897), (0.9893) and (0.9837) and for weibull model r2 values were found to be (0.9937), (0.9953) and (0.9915).

Conclusion: In this study successful application of Pharmacopeial and non Pharmacopeial tests on three different selected brands in Karachi, Pakistan were carried out however further work is recommended on large sample. Results were found to be in limit in accordance to the United States Pharmacopeia. Invitro multiple points interval dissolution studies were conducted at phosphate buffer pH 5.8 the data were subjected to several kinetic models by the application of Dissolution Data (DD solver) an add in program in Excel to determine release kinetics. Study demonstrated that all selected brands of Paracetamol 500 mg tablets followed first order kinetics and weibull model.