Functional DNAzyme-Guided Target Identification and Portable Detection of Colorectal Cancer.

Rapid discrimination of colorectal cancer (CRC) at the time of tissue sampling remains clinically challenging. Although DNAzyme-based assays enable selective analysis of complex biological samples, their diagnostic translation is constrained by undefined endogenous activators. Here, using an iterative DNAzyme activity-guided isolation strategy that integrates chromatographic fractionation with affinity enrichment, we identified malic enzyme 1 (ME1) as the molecular activator of a DNAzyme newly selected against colorectal cancer tissue lysates. The ME1-triggered catalytic reaction was then translated into a lateral flow format, enabling instrument-free visual detection within 35 min. In clinical specimens, the platform discriminated CRC from low- and high-grade intraepithelial neoplasia with an AUC of 0.98. By defining the molecular basis of DNAzyme activation and coupling it to a portable readout, this work provides a direct route from evolving DNAzyme probes for sensing complex tissues to rapid, near-point-of-care detection of CRC.