A Competitive Immunoassay for Dehydroepiandrosterone Sulfate in Dried Blood Spots

Dehydroepiandrosterone sulfate (DHEA-S) is a steroid hormone commonly measured to assess neuroendocrine activity related to HPA-axis function, stress physiology, and broader health outcomes, with significance for Human Biology research. To facilitate research assessing DHEA-S concentrations using minimally invasive sample collection methods, we present validation results for a competitive immunoassay to quantify DHEA-S in dried blood spots (DBS) collected via finger prick. Results demonstrate acceptable levels of inter- and intra-assay variation, linearity of dilution, lowest limit of detection, and agreement between matched DBS and plasma samples (Pearson's R = 0.96). The protocol presented here using a modified commercially available assay kit offers a practical alternative for evaluating DHEA-S in a wide range of settings.