Determination of vitamin E in infant formula by dispersive liquid liquid microextraction combined with high performance liquid chromatography-UV detection

Vitamins are required in small quantities for normal metabolism. Humans cannot synthesize these nutrients, so they should be obtained from food. Vitamin E (α-tocopherol) is a fat soluble vitamin that serves as a powerful biological antioxidant which is essential for normal function of immune system. Early life nutrition is important for future health. Low vitamin E intake in infancy is associated with asthma and hemolytic anemia in infants. However, high intake of vitamin E is associated with liver and kidney failure. Therefore, quality control of vitamin E in infant formula is essential and developing an analysis method is required for vitamin quantification. In this study, dispersive liquid liquid microextraction (DLLME) combined with high performance liquid chromatography-UV detection (HPLC-UV) was developed for determination of vitamin E in infant formula [1-3].In this work after dissolving of infant formula powder in water, protein precipitation was done by acetonitrile. Then, DLLME method by chloroform and acetonitrile as extraction and dispersing solvents, respectively was developed for cleanup and pre-concentration of vitamin E in infant formula samples and followed HPLC-UV at 296 nm. The method was validated and applied to the determination of vitamin E in the infant formula samples.Under the optimum conditions, the method provided a linear range between 10-125 mg/L with a correlation coefficient (R2) of 0.99. Limit of detection and limit of quantification were 5.0 and 16.8 mg/L, respectively. A sensitive DLLME method coupled with HPLC-UV was developed and validated for quantitation of vitamin E in infant formula samples.Dispersive Liquid–liquid microextraction, infant formula, vitamin E, high-performance liquid chromatography.