[Determination of vitamin A, vitamin E isomers and cholesterol in foods by reversed-phase high-performance liquid chromatography].

OBJECTIVE: To establish a method for simultaneous analysis of vitamin A, three vitamin E isomers and cholesterol in meat products by reversed-phase high-performance liquid chromatography. This method is used to determine the contents of the corresponding nutrients in several meat products. METHODS: The sample was pretreated with saponification and liquid-liquid extraction, then separated on Waters Symmetry C_(18) column(4.6 mm×250 mm, 5 μm). The mobile phase consisted of methanol(98%) and water(2%). The analytes were detected by photo-diode array(PDA)detector. 325 nm, 294 nm, and 210 nm were selected as the characteristic absorption wavelengths of vitamin A, vitamin E, and cholesterol, respectively by scanning in the range of 190-350 nm in 3 D mode. Benzo[e]pyrene was internal standard for vitamin A and E. Cholesterol was quantified by external standard curve method. RESULTS: The concentration of vitamin A, three vitamin E isomers and cholesterol showed good linearity in the range of 0.18-9.00 μg/mL、0.76-5.2 μg/mL and 0.11-5.50 mg/mL, respectively, with the correlation coefficients greater than 0.995.The limits of detections(LODs) were 5、20 and 330 μg/100 g and the limits of quantification(LOQs) for vitamin A, three vitamin E isomers and cholesterol were 15、60 and 990 μg/100 g, respectively. The recoveries at three levels in the matrix were 86.3%-105.6%, and the relative standard deviations(RSDs) were all less than 7.0%(n=6). CONCLUSION: The method is sensitive, accurate and suitable for analysis of vitamin A, three vitamin E isomers and cholesterol in meat products.