Abstract
A simple isocratic reversed‐phase high performance liquid chromatographic (HPLC) method was developed for the determination of 2‐(4‐isobutylphenyl) propionic acid and its major impurity 4‐isobutylacetophenone in a gel formulation. The chromatographic separation was achieved with sodium phosphate buffer (pH 3.0) and methanol (40:60, v/v) as mobile phase, a ChromSpher C18 column (100 mm×3 mm and 5 µm), and UV detection at 220 nm. The analysis time was less than 10 min. The method was validated with respect to linearity, range, precision, accuracy, specificity, and robustness. The calibration curves showed good linearity over the concentration range of 0.10–80 µg/mL. The correlation coefficients were ≥0.9997 in each case. The RSD values for intra‐ and inter‐day precision studies were less than 0.50%. The procedure described here is simple, selective, and is suitable for routine quality control analysis.