Estimation of Metaxalone in Bulk and in Tablet Dosage Form by RP-HPLC

A simple, selective, rapid and precise RP-HPLC method for the estimation of Metaxalone in bulk material and in pharmaceutical formulation has been developed and validated. An isocratic elution at a flow rate of 1.0 ml/min was employed on a Phenomenax Luna C18 column (150 X 4.6 mm i.d., 5 μ) at ambient temperature. The mobile phase consisted of Phosphate buffer: p^H (5.0) Acetonitrile: Methanol in the ratio of (40:40:20). The UV detection wavelength was documented at 280 nm. The retention time Metaxalone was found to be 4.19 min. The method obeys Beer's Law in the concentration range of 20–100 μg/ml. The method was validated as per standard analytical procedures. The correlation co-efficient value was found to be 0.9997. The limit of detection and the limit of quantification were found to be 0.0.3205 μg/ml and 0.9712 μg/ml respectively. The amount of Metaxalone present in formulation was found to be 399.98 mg. The method was validated statistically and by recovery studies. Hence, the proposed method can be proficiently applied for the routine analysis of Metaxalone in bulk and in tablet formulation.