One-step pipetting and assembly of encoded chemical-laden microparticles for high-throughput multiplexed bioassays

One quantitative liquid handling method in conventional assay processes is pipetting, which delivers a precise volume of one sample at a time. As this process becomes laborious and time-consuming as the number of samples increases, researchers in individual laboratories need a way to conduct large-scale assays in a reasonable amount of time and at an affordable cost. Here we report a novel handling technique of chemical substances termed ‘partipetting’, which allows the one-step pipetting of various chemical-laden hydrogels. We pipette and assemble various types of encoded chemical-laden microparticles in microwell arrays in parallel. The combination of this heterogeneous particle chip and a cell chip induces the release of the chemicals from the hydrogels and, eventually, the chemicals treat the targets. Based on bioassay applications using partipetting, we show its capability in large-scale bioassays, without the need for high-throughput bioassay resources, owing to a reduction in the assay costs and time. High-throughput screening allows for the rapid assessment of biochemical compounds and processes, but with increasing scale comes increasing costs. Here, the authors use an array of lithographically encoded hydrogel microparticles as a more accessible screening technique.