VALIDATION OF A SIMPLE REVERSED PHASE-HPLC METHOD FOR THE DETERMINATION OF BACLOFEN IN TABLETS

Abstract

Baclofen is a muscle relaxant used as a first option to treat spasticity and muscle spasms in patients with spinal cord injuries, which is available in Brazil as 10 mg tablets. The compendia methods employ HPLC by ion pairing that requires the use of specific reagents and column conditioning, increasing the waste generation and the cost of analysis. In this study, an isocratic, simple and stability-indicating HPLC method was validated to assay baclofen tablets. A C-18 column (Luna®, 150 x 4.6 mm, 5μm), mobile phase composed by triethylamine 10 mM pH 7.0, methanol and acetonitrile (80:15:5), flow rate 1 mL/min and detection at 220 nm was used. The baclofen retention time was 6.2 min and the method was linear in the range of 5 – 100 μg.mL^-1 (r = 0.9999). Method selectivity was demonstrated by the forced degradation study and simultaneous analysis of baclofen impurity. The method showed accuracy (mean recovery 99.27%) and precision (RSD < 2%). The robustness was evaluated by factorial design, and the method was robust robust regarding the proposed variations. The developed method met the requirement of current guidelines, being indicative of stability and suitable for the determination of baclofen in tablets.