Microfluidic encapsulation of supramolecular optical chemosensors for high-throughput analysis and screening

The binding fluorescence dye by supramolecular interactions to form optical chemosensors is a powerful sensing method allowing ultra-high selectivity for the target analyte and fast response of the detection. While notable success has been made to develop various supramolecular optical chemosensors, there is little effects contributed to the high throughput assays. Here we introduce a droplet-based microfluidic detection and screening system using supramolecular optical chemosensors to measure the enzyme activity and elucidate their prospects for high throughput screening. The supramolecular optical chemosensors derives from cucurbit[8]uril (CB[8])-mediated host-guest chemistry for macrocycle-dye complex formation. The encapsulation of CB[8]-dye in millions of picolitre microdroplets provides an efficient platform for handing a large number of parallel experiments, allowing for shorter processing time and reducing the needs for analyte volume. Further, the supramolecular optical chemosensors in microdroplets are used in measuring of the biocatalysis efficiency of enzyme immobilized hydrogel microparticles (HMPs), which also has been applied for high throughput screening. This label-free and robust approach of supramolecular optical chemosensors in microdroplets platform could be transferable to single-cell analysis and rapid selection of cells.