A Smartphone-Mediated “All-In-One” Biosensing\nChip for Visual and Value-Assisted Detection

A smartphone-mediated\nself-powered biosensor is fabricated for\nmiRNA-141 detection based on the CRISPR/Cas12a cross-cutting technique\nand a highly efficient nanozyme. As a novel nanozyme and a signal-amplified\ncoreaction accelerator, the AuPtPd@GDY nanozyme exhibits an excellent\nability to catalyze cascade color reactions and high conductivity\nto enhance the electrochemical signal for miRNA-141 assays. After\nCRISPR/Cas12a cross-cutting of S2-glucose oxidase (S2-GOD), the electrochemical\nsignal is weakened, and miRNA-141 is detected by monitoring the decrease\nin the signal. On the other hand, a cascade reaction among glucose,\nH<sub>2</sub>O<sub>2</sub>, and TMB is catalyzed by GOD and AuPtPd@GDY,\nrespectively, resulting in a color change of the solution, which senses\nmiRNA-141. The self-powered biosensor enables value-assisted and visual\ndetection of miRNA-141 with limits of detection of 3.1 and 15 aM,\nrespectively. Based on the dual-modal self-powered sensing system,\na smartphone-mediated “all-in-one” biosensing chip is\ndesigned to achieve the real-time and intelligent monitoring of miRNA-141.\nThis work provides a new approach to design multifunctional biosensors\nto realize the visualization and portable detection of tumor biomarkers.