Impact of Chromatographic Effects on Spotting Cards and Inconsistent Manual Spotting on Drug Quantitation in Dried Saliva Spots

摘要

It is still challenging to develop a reliable assay for dried saliva spots due to sample-to-sample variation in the physical properties of the liquid saliva, as well as spotting technique. We proposed a new hypothesis to explain variability in DSS samples and results: variations in analyte distribution in spots could result from either "surface tension" when tip touching the cards, or "capillary motion" when tip not touching the cards during sample preparation. We evaluated the potential chromatographic effects regarding analyte distribution during spotting on the cards, caused by two spotting techniques: "touching" and "not touching" the card while spotting.