Determination Of Folate, Nicotinic Acid, Biotin And Pantothenic Acid In Food By Using UPLC-MS/MS

Water-soluble vitamins are kinds of necessary trace substances for maintaining physiological function of human body. Determination of their contents have a very important role in food nutrient control. Methods have been developed for the determination of folate, niacin, biotin and pantothenic acid in foods by ultraperformance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS). The main research results are as follows:(1) Developed an UPLC-MS/MS-SPE method to determination folic acid and 5-methyltetrahydrofolic acid in foods. Multivitamins dissolved with water and extracted with ultrasonic extraction; milk powder, corns and eggs dissolved with phosphate buffer and extracted by three-enzyme-SPE treatment. The mobile phase was 10 mmol/L ammonium acetate solution with 0.1% formic acid and acetonitrile, test by the positive ion mode and multiple reaction monitoring(MRM) mode. Folic acid and 5-methyltetrahydrofolic acid had a good linearity within 1~450 ng/m L and 1~300 ng/m L, the correlation coefficient were all greater than 0.999. The method’s limit of detection(LOD) and limit of quantitation(LOQ) were 0.4 ng/m L and 1.0 ng/m L for folic acid, the method’s limit of detection(LOD) and limit of quantitation(LOQ) were 1.0 ng/m L and 2.9 ng/m L for 5-methyltetrahydrofolic acid. For three spiked levels, the average recoveries obtained ranged between 92.1%~118.1%, intra-day and inter-day relative standard deviation were within 1.49%~5.99%.(2) Developed an UPLC-MS/MS-SPE method to determination niacin in foods. Samples were hydrolyzed by 0.2 mol/L Na OH at 121℃ for 30 min and then purified by HLB cartridge. The mobile phase was 10 mmol/L ammonium acetate solution with 0.1% formic acid and acetonitrile, test by the positive ion mode and multiple reaction monitoring(MRM) mode. nicotinic acid had a good linearity within 1~200 ng/m L, the correlation coefficient were all greater than 0.999. The instrument’s limit of detection(LOD) and limit of quantitation(LOQ) were 0.04 ng/m L and 0.1 ng/m L. For three spiked levels, the average recoveries obtained ranged between 92.8%~113.4%, intra-day and inter-day relative standard deviation were most below 10%.(3) Developed an UPLC-MS/MS method to determination biotin in foods. Multivitamins and milk powder dissolved with water and extracted with ultrasonic extraction; corns and eggs hydrolyzed with 2 mol/L H2SO4 at 121℃ for 30 min. The mobile phase was 10 mmol/L ammonium acetate solution with 0.1% formic acid and acetonitrile, test by the positive ion mode and multiple reaction monitoring(MRM) mode. Biotin had a good linearity within 1~50 ng/m L, the correlation coefficient were greater than 0.999. The method’s limit of detection(LOD) and limit of quantitation(LOQ) were 0.4 ng/m L and 1.0 ng/m L. For three spiked levels, the average recoveries obtained ranged between 87.3%~110.3%, intra-day and inter-day relative standard deviation were below 10%.(4) Developed an UPLC-MS/MS method to determination pantothenic acid in foods. Multivitamins and milk powder dissolved with 10 mmol/L ammonium acetate solution and extracted with ultrasonic extraction; corns and eggs hydrolyzed with 10 mmol/L ammonium acetate solution at 121℃ for 30 min. The mobile phase was 10 mmol/L ammonium acetate solution with 0.1% formic acid and acetonitrile, test by the positive ion mode and multiple reaction monitoring(MRM) mode. Pantothenic acid had a good linearity within 1~500 ng/m L, the correlation coefficient were all greater than 0.999. The method’s limit of detection(LOD) and limit of quantitation(LOQ) were 0.4 ng/m L and 1.0 ng/m L. For three spiked levels, the average recoveries obtained ranged between 93.6%~108.3%, intra-day and inter-day relative standard deviation were below 10%.The new developed methods were proved to be simple and sensitive, which could overcome the deficiencies of microbiological method and HPLC method.