Extraction of vitamin D metabolites from human serum using ISOLUTE SLE+ in 96-fixed well plate format prior to LC-MS/MS analysis

ISOLUTE SLE+ Supported Liquid Extraction plates and columns offer an efficient alternative to traditional liquid-liquid extraction (LLE) for bioanalytical sample preparation, providing high analyte recoveries, no emulsion formation and significantly reduced sample preparation time.

Vitamin D deficiency can result in a variety of health issues such as osteoporosis, liver and kidney problems, it is often associated with increased risk of cancers and multiple sclerosis. From this standpoint vitamin D monitoring is on the rise and of significant clinical relevance.

The method in this application note describes the use of ISOLUTE SLE+ plates for the efficient and simple extraction of the vitamin D metabolites 25-OH vitamin D2 and 25-OH vitamin D3. Incorporated into the procedure is an integral protein binding disruption step which maximizes analyte recovery and eliminates the need for any offline protein disruption. The method has been internally validated using DEQAS approved serum samples and deuterated internal standards the results obtained are better than that required for criteria for acceptable performance for DEQAS approval. All recoveries were consistently greater than 90% with all RSDs < 10% at LOQs of 1-3.75 ng/mL.