Abstract
An HPLC method for the determination of partially hydrogenated terphenyls-based thermal heating fluid, Therminol 66™, in various vegetable oils is described. Direct analysis of palm olein showed that the 3- and 4-cyclohexylbiphenyl peaks of the Therminol 66™ used in quantitative analysis co-eluted with other fluorescent peaks present naturally in the oil. However, those interfering peaks were readily removed after saponification of palm olein. The concentrations of the 3- and 4-cyclohexylbiphenyls of Therminol 66™ were monitored by fluorescence detection at 257 (excitation) and 320 nm (emission). The calibration graph obtained by using the peak areas of the 3- and 4-cyclohexylbiphenyls against the concentrations of Therminol 66™ was linear, with a correlation coefficient of 0.994. The limit of quantitation, using spiked palm olein, was as low as 0.2 μg/g. The coefficients of variation obtained from the intra- and interday studies obtained by using three spiked concentrations (0.2, 0.5, and 1.0 μg/g) were 1.76–6.43 and 3.77–10.4%, respectively. The mean recovery value obtained from sunflower, soybean, and canola oils was more than 88.7%.
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Moh, M.H., Tang, T.S. & Tan, G.H. Determination of partially hydrogenated terphenyls-based thermal heating fluid in vegetable oils by HPLC with fluorescence detection. J Amer Oil Chem Soc 79, 379–382 (2002). https://doi.org/10.1007/s11746-002-0492-8
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DOI: https://doi.org/10.1007/s11746-002-0492-8