Analysis of Vitamin A in Jordanian Local Fresh Milk Samples Using Liquid Chromatography Tandem-Mass Spectrometry, LC/MS/MS

An auspicious method for the quantitative determination of vitamin A (retinol) was augmented in seven different Jordanian local fresh milk samples using liquid chromatography tandem -mass spectrometry (LC/MS/MS). The compound was separated with C18 Thermo fisher gold (4.50 x100 mm x 5 A) column through a flow rate of 1 mL/min with isocratic mobile phase. Vitamin A acetate was used as an internal standard .The method was validated using triplicate analyses, relative recovery experiment and statistical analysis. Liquid- liquid extraction was employed as a pre-concentration step with n-hexane -dichloromethane mixture (90%:10%) as an extraction solvent. The concentration range of the working standards was 0.0-1000.0 ng/mL. The correlation coefficient was found to be 0.9994. The limit 0f detection and limit of quantification were found to be 0.53 and 1.78 respectively. The 95% confidence interval was calculated to be 49.032 + 0.22. This technique showed reasonable recovery of 98.08%, coefficient of variation of 0.36%, standard deviation of 0.178 and error of -48.032. The ranges of the calculated concentrations of the vitamin A were found to be from 6.47 ng/mL- 46.35 ng/mL.