Optimization and validation of high‐performance liquid chromatographic method for the determination of dowtherm ATM in edible oils and oleochemicals

A method using high‐performance liquid chromatography and fluorescence detection is optimized and validated for the determination of Dowtherm ATM in spiked oleochemicals and edible oils. The samples are directly injected into a reversed‐phase C18 column, and Dowtherm A is detected using a fluorescence detector set at 247 nm excitation and 310 nm emission wavelengths. The simple isocratic mobile phase used is a mixture of methanol and water (90∶10, vol/vol) at a flow rate of 1 mL/min. The limits of quantitation are from 0.1 to 0.2 μg/g. Mean recoveries ranged from 93.0 to 116% with reproducibilities of 1.29–3.84%. The procedure provides a simple, reliable and sensitive method for determining Dowtherm A residue in oleochemicals and edible oils without prior sample cleanup or extraction.