%0 Journal Article %T Application of HPLC for the Simultaneous Determination of Paracetamol, Chlorzoxazone, and Nimesulide in Pharmaceutical Dosage Form %A Snehal J. More %A Suparna S. Tandulwadkar %A Ajinkya R. Nikam %A Atul S. Rathore %A L. Sathiyanarayanan %A Kakasaheb R. Mahadik %J ISRN Chromatography %D 2012 %R 10.5402/2012/252895 %X A simple, precise, and accurate reversed-phase liquid chromatographic method has been developed for the simultaneous determination of paracetamol (PCM), chlorzoxazone (CHZ), and nimesulide (NIM) in pharmaceutical dosage form. The chromatographic separation was achieved on a Thermo Hypersil GOLD C18 column (250 ¡Á 4.6£¿mm i.d., 5£¿¦Ìm particle size). The mobile phase consisted of water£¿:£¿acetonitrile (55£¿:£¿45 v/v). The flow rate was set to 1.2£¿mL min£¿1 and UV detection was carried out at 275£¿nm. The retention time ( ) for PCM, CHZ, and NIM was found to be 2.69 ¡À 0.02, 4.61 ¡À 0.01, and 9.55 ¡À 0.02 min, respectively. The validation of the proposed method was carried out for linearity, precision, robustness, limit of detection, limit of quantitation, specificity, and accuracy. The linear dynamic ranges were 32.5¨C65.0£¿¦Ìg£¿mL£¿1 for PCM, 37.5¨C75.0£¿¦Ìg£¿mL£¿1 for CHZ, and 10.0¨C20.0£¿¦Ìg£¿mL£¿1 for NIM. The developed method can be used for routine quality control analysis of titled drugs in pharmaceutical dosage form. 1. Introduction Multiple component formulations have been taking up the market nowadays due to their synergistic effects, quick relief, multiple actions, tolerability, and patient acceptance. Many such combinations are available in market, one of such formulations is combination of Paracetamol (PCM), Chlorzoxazone (CHZ), and Nimesulide (NIM). Paracetamol (PCM) (Figure 1), (N-(4-hydroxyphenyl)acetamide, is a para-aminophenol derivative and nonopiate, nonsalicylate, centrally and peripherally acting analgesic agent. It has weak anti-inflammatory effects. The most commonly consumed daily dose, 1000£¿mg, results in roughly 50% inhibition of both COX-1 and COX-2 in whole blood assays ex vivo in healthy volunteers. It has been suggested that COX inhibition might be disproportionately pronounced in the brain, explaining its antipyretic efficacy and its direct activity on the centre for the body temperature regulation in the hypothalamus. It is official in Indian Pharmacopoeia (IP) and British Pharmacopoeia (BP). Both IP and BP suggest titrimetric and UV spectrophotometric assay method for paracetamol in bulk and tablet formulations [1¨C3]. Figure 1 Chlorzoxazone (CHZ) (Figure 1), (5-chloro-2(3H)-benzoxazolone), inhibits histamine release and has skeletal muscle relaxant property. It is used to decrease muscle tone and tension and thus to relieve spasm and pain associated with musculoskeletal disorders. It is official in United States Pharmacopeia (USP) [4, 5]. Nimesulide (NIM) (Figure 1), N-(4-nitro-2-phenoxyphenyl) methanesulfonamide, is a derivative of %U http://www.hindawi.com/journals/isrn.chromatography/2012/252895/