Integrating commercial personal glucose meter with peroxidase-mimic DNAzyme to develop a versatile point-of-care biosensing platform

The development of point-of-care testing (POCT) methods is highly desirable in molecular detection, as they enable disease diagnosis and biomarker monitoring on-site or at home. Repurposing existing POCT devices to detect diverse biomarkers is an economical way to develop new devices for POCT use. Personal glucose meter (PGM) is one of the most used off-the-shelf POCT devices that has been reused to detect non-glucose targets. However, developing a label-free, user-friendly, and cost-effective general PGM-based sensing platform remains a great challenge, primarily due to the reliance on protein enzymes in most existing signal transducing strategies. To overcome the challenges, we herein developed a DNAzyme-based signal transduction strategy that bridges non-glucose signals to PGM readouts. By integrating this strategy with CRISPR/Cas12a-mediated target sensing, we successfully established a simple and versatile platform (CaG-PGM) for biosensing. The utility of CaG-PGM in the detection of nucleic acid targets was successfully validated by detecting Monkeypox virus DNA and SARS-CoV-2 RNA with high sensitivity and specificity. We further demonstrated its generality in detecting non-nucleic acid targets including protein and small molecule. In conclusion, this study provides a cheap and effective strategy for repurposing PGM as a general biosensing platform and sheds new light on translating functional nucleic acids for POCT applications.