Abstract: Disclosed are methods and systems for detecting SARS-CoV-2 analytes in dried samples, as for example, dried blood spots. For example, disclosed is a method for measuring an analyte of interest in a dried sample comprising: (a) obtaining a dried sample from a subject; (b) extracting the analyte of interest from the dried sample; and (c) detecting the analyte of interest extracted from the dried sample. In certain embodiments, the analyte of interest is an analyte specific to SARS-CoV-2. Also, the method may include a step of determining a cutoff index (COI) indicative of whether the subject has a detectable amount of the analyte of interest and so is defined as positive, or does not contain a detected amount of the analyte of interest and so is defined as negative, or is defined as indeterminate.

Abstract: Disclosed are methods and systems using liquid chromatography/tandem mass spectrometry (LC-MS/MS and 2D-LC-MS/MS) for the analysis of ascorbic acid in biological samples.