{Reference Type}: Journal Article {Title}: Quantification of fat-soluble vitamins and their metabolites in biological matrices: an updated review. {Author}: Zhang Y;Bala V;Mao Z;Chhonker YS;Murry DJ; {Journal}: Bioanalysis {Volume}: 12 {Issue}: 9 {Year}: May 2020 {Factor}: 2.695 {DOI}: 10.4155/bio-2020-0069 {Abstract}: Fat-soluble vitamins (FSVs) are micronutrients essential in maintaining normal physiological function, metabolism and human growth. Ongoing increased awareness regarding FSV concentrations and their impact on human growth along with disease progression warrant the need of developing selective and sensitive analytical methods. LC-MS/MS is currently the method of choice for accurate quantitation of FSVs. However, there are multiple approaches for extraction, separation and calibration of FSVs in biological matrices. This review discusses recent LC-MS/MS methods for the simultaneous quantification of FSVs in biological matrices and summarizes sample pretreatment procedures, chromatographic conditions and calibration approaches. Current challenges and clinical applications in various disease states are also highlighted.