Abstract
Here we report a method, smol-seq (small-molecule sequencing), using structure-switching aptamers (SSAs) and DNA sequencing to quantify metabolites. In smol-seq, each SSA detects a single target molecule and releases a unique DNA barcode on target binding. Sequencing the released barcodes can, thus, read out metabolite levels. We show that SSAs are highly specific and can be multiplexed to detect multiple targets in parallel, bringing the power of DNA sequencing to metabolomics.