Validated stability indicating RP-HPLC method for determination of paracetamol, methocarbamol and their related substances

Abstract

Paracetamol (PAR) and methocarbamol (MET) are co-formulated together in MethorelaxÒ tablets which are widely used as a muscle relaxant and in the treatment of muscle-skeletal pain. On the other hand, 4-aminophenol (4-AP) and guaifenesine (GU) have been reported to be related substances and degradation products of PAR and MET, respectively. The target of this work was to develop and validate a simple, sensitive and selective stability indicating RP-HPLC method for the determination of PAR, MET, 4-AP and GU in their bulk powders and laboratory prepared mixtures. Chromatographic separation was achieved within 10 minutes with the required asymmetry, accuracy and precision on ODS column using 0.05 M KH 2 PO 4 buffer : acetonitrile (72.5 : 27.5, v/v, pH ¼ 6) as the mobile phase at a flow rate of 1 mL min À1 with UV detection at 225 nm. The developed method has been validated as per ICH guidelines and the calibration plots were linear over the concentration ranges of 3-20, 4-25, 0.6-8 and 0.6-8 mg mL À1 for PAR, MET, 4-AP and GU, respectively. The method has been successfully applied in the analysis of MethorelaxÒ tablets and good results were obtained. Moreover, its results have been compared to a previously reported RP-HPLC method and no significant difference was found between the two methods.

Electroanalytical Investigation on Paracetamol on Boron-Doped Diamond Electrode by Voltammetry

“…A number of methods are available to determine paracetamol in various types of samples [5]. These methods include capillary electrophoresis (CE) [6], high performance liquid chromatography (HPLC) [7], liquid chromatography-mass spectrometry (LC-MS) [8], UV spectrophotometry [9], HPLC-mass spectrometry and thermogravimetric analysis (TGA) [10]. Unfortunately, these techniques are expensive and need costly maintenance.…”

Determination of flutamide and two major metabolites using HPLC–DAD and HPTLC methods

“…The methods were extended for determination of the active drug and the studied metabolites in biological fluids including human plasma and urine. Nowadays, chromatographic methods became the analytical methods of choice for qualitative and quantitative pharmaceutical analysis [ 23 – 26 ].…”

“…Chromatographic methods are widely used for qualitative and quantitative analysis. It is used for resolving complex mixtures [ 22 ], during stability studies [ 23 ], determination of drugs and their impurities [ 24 ], and determination of drugs in biological fluids [ 24 ].…”

Disposable Biosensor Based on Amidase/CeO2/GNR Modified Inkjet‐printed CNT Electrodes‐droplet Based Paracetamol Detection in Biological Fluids for “Point‐of‐care” Applications

“…Due to the above‐mentioned restrictions, the development of fast and accurate analytical methods for the detection and monitoring of APAP is of the great importance. Various methods have been reported for this purpose, including chromatographic , spectrophotometric and thermogravimetric techniques . These techniques have limitations in terms of complex sample preparation, instrumentation costs and the need for skilled operators, which are restricting on‐site measurements.…”