A new convenient methodology based on dihydropyridine derivative for selective fluorimetric analysis of baclofen: Application to spiked urine and content uniformity evaluation.

Baclofen belongs to skeletal muscle relaxant and is used for the treatment of muscle spasticity that originated from multiple sclerosis or a spinal cord injury and other cases as hiccups. In the current analytical study, a new, convenient and selective fluorimetric method for baclofen analysis has been developed and validated. The analytical methodology depends on Hantzsch reaction that leads to formation of dihydropyridine fluorescent derivative. The primary amino moiety in baclofen condensed with two equivalents of acetylacetone in the presence of formaldehyde and acetate buffer solutions. Spectrofluorimetric monitoring of the product was accomplished at emission wavelength of 477.3 nm after excitation at 419.9 nm. The method exhibited linearity when baclofen concentration plotted against the fourescence response in the range of 0.3-6.0 µg/mL. Adjustment of the reaction variables and studying validation parameters according to directives of ICH were performed perfectly. Ultimately, the proposed approach was applied successfully for baclofen analysis in raw material, dosage form and spiked urine and it was also extended to test content uniformity.