25-Hydroxyvitamin D2/D3 Analysis in Human Plasma Using LC-MS

One of the biggest debates in clinical medicine currently revolves around understanding the proper levels of vitamin D in patients' plasma. Besides well-known diseases like rickets and osteomalacia, vitamin D deficiency has been linked to cancer and heart disease and is rapidly becoming the most widely used liquid chromatography mass spectrometry (LC-MS)-based clinical test. Increases in testing frequency have required more rapid and cost-effective solutions for determining vitamin D levels in plasma. An LC-MS method for vitamin D-2/D-3 was adapted for use with core-shell columns to achieve run times of less than 4 min. This method provides rapid, sensitive, rugged, and robust LC-MS-MS analysis of vitamin D levels in patient serum (LOD of 1 and 2 ng/ml for 25-OH D-3 and 25-OH D-2, respectively, with CV of 4-7%) and speeds the diagnosis by hospital and clinical laboratories of potential vitamin D deficiencies.