xPlex

Changes in metabolite concentrations are often more drastic than changes in gene and protein expression levels, and thus they could provide a highly sensitive measure of disease or therapeutic status. Multiplexed quantification of small molecules has been challenging due to high background signal, limited readout mechanisms, and signal cross-over. Here, we introduce an aptamer-based assay that quantifies small molecules with low background and high multiplexing capabilities by mapping small molecules to DNA aptamers for quantification via high throughput sequencing. In a proof-of-concept example, we show that we can quantify mixtures of small molecules via next generation sequencing, and that it is highly amenable for characterization of SELEX schemas in high-throughput.