5. Method Optimization for High-Throughput 25-OH Vitamin D Analysis: The Devil is in the Details
Mon 12:12 PM - PosterSplash Track 1
Julia Drees
Kaiser Permanente
View Long Abstract
We investigated the use of protein precipitation plates with phospholipid removal chemistry and a range of parameters affecting detection and separation of 25-OH Vitamin D2/D3 in the quest for a robust LC-MSMS method with a throughput of 50 samples/hour. The relative abundance of dehydrated versus intact precursor ions was affected by small changes in source temperature and the use of acetonitrile versus methanol in the mobile phase. Retention time differences of just 0.2 minutes altered peak areas several fold – presumably due to ion suppression. Reducing autosampler delay by seconds and decreases in dead volume greatly improved throughput.