Single wavelength check isocratic reverse phase HPLC method for fast and direct estimation of alkyl aromatic oxidation products

Abstract

An isocratic, reverse phase liquid chromatographic method has been developed for the quantitative determination of p-xylene oxidation products. The method represents a direct and fast analytical procedure to determine the assay. Separation is achieved on Waters μ-Bondapak C18, 300 mm × 3.9 mm × 10 μm column in a single wavelength 230 nm. The method has been validated with respect to linearity, limit of quantification, accuracy and robustness. Critical impurity 4-carboxy benzaldehyde (4-CBA) is found to be within the limit of quantification, 8 ppm, accuracy 97–98%, recovery 98 to 101% and resolution 1.97 from the closest peak. The sample solution is stable and can be used safely within 48 h. The method is verified by real sample reaction mixture.