Stability Indicating LC-Method for Estimation of Paracetamol and Lornoxicam in Combined Dosage Form

Dimal A Shah

doi:10.3797/scipharm.1012-03

Abstract

A simple, specific and stability indicating reversed phase high performance liquid chromatographic method was developed for the simultaneous determination of paracetamol and lornoxicam in tablet dosage form. A Brownlee C-18, 5 μm column having 250×4.6 mm i.d. in isocratic mode, with mobile phase containing 0.05 M potassium dihydrogen phosphate:methanol (40:60, v/v) was used. The flow rate was 1.0 ml/min and effluents were monitored at 266 nm. The retention times of paracetamol and lornoxicam were 2.7 min and 5.1 min, respectively. The linearity for paracetamol and lornoxicam were in the range of 5–200 μg/ml and 0.08–20 μg/ml, respectively. Paracetamol and lornoxicam stock solutions were subjected to acid and alkali hydrolysis, chemical oxidation and dry heat degradation. The proposed method was validated and successfully applied to the estimation of paracetamol and lornoxicam in combined tablet dosage form.

Highlights

Lornoxicam (LRN) is chemically 6-chloro-4-hydroxy-2-methyl-N-(pyridin-2-yl)-2Hthieno[2,3-e][1,2]thiazine-3-carboxamide 1,1-dioxide
The combination dosage form of paracetamol and lornoxicam is available in the market and it is indicated in the treatment of rheumatism and in reduction of post operative pain
Literature survey revealed that liquid chromatographic (LC) [4, 5], LC-electrospray tendem mass spectrometry [6, 7] methods have been reported for the estimation of lornoxicam

Summary

Introduction

Lornoxicam (LRN) is chemically 6-chloro-4-hydroxy-2-methyl-N-(pyridin-2-yl)-2Hthieno[2,3-e][1,2]thiazine-3-carboxamide 1,1-dioxide. Stock solutions were prepared by accurately weighing 25 mg each of PCM and LRN and transferring to two separate 25 ml volumetric flasks containing 10 ml of methanol. Appropriate volume of the aliquot was transferred to a 10 ml volumetric flask and the volume was made up to the mark with the mobile phase to obtain a solution containing 100 μg/ml of PCM and 1.6 μg/ml of LRN.

Results

Conclusion