Drip-Dry Strategy Assisted Blu-Ray Disc Biosensor for Fast Point of Care Testing.

Discs and numerous other consumer products have been developed for point of care testing (POCT) to replace traditional large and expensive biochemical devices in certain scenarios. Herein, we propose a drip-dry strategy (2D strategy) assisted Blu-ray disc (BD) biosensor, termed BDB, for rapid and portable POCT within 30 min with the cost of a single test < $1. The platform utilizes the covered area formed by the deposition of the substance to be measured on the activated BD surface after the evaporation of water and realizes the quantitative detection of the target through the error readout of free disc quality diagnosis software. As a proof of concept, we first demonstrated the feasibility of direct quantitative detection of substances in solution in a single system through the detection of pure proteins avoiding colorimetric reagent used in traditional optical detection. For the complex mixed systems, we then innovatively utilize the principle that soluble targets promote/inhibit the dissolution of insoluble precipitates to achieve specific detection of targets and successfully apply BDB to the indirect quantitative detection of glutathione (GSH) with LOD of 0.447 mM in the range of 2-16 mM and organophosphorus pesticides (OPs) with LOD of 2.122 × 10 -7 M in the range of 1.289 × 10 -7 -1.289 × 10 -4 M. The BDB is widely applicable, easy to operate, and less time-consuming, which is anticipated to provide an alternative method for early, on-site detection or screening.