Mismatch-introduced crRNA guided PCR-CRISPR/Cas12a platform improves EGFR point mutation detection in single tumor cell.

Dynamic monitoring of epidermal growth factor receptor (EGFR) mutations is essential for the early identification of resistance and treatment adaptation. Single-cell heterogeneity analysis is crucial for precision cancer medicine, yet sensitive and specific detection methods for individual tumor cells remain challenging. Here, we develop a PCR-CRISPR/Cas12a platform enhanced by the incorporation of mismatched base in crRNA at specific site for single-cell point mutation detection. This platform demonstrated high specificity and sensitivity, detecting point mutation at a frequency of 0.1% and in as low as 1.02 ng of genomic DNA, which represents an improvement over the amplification-refractory mutation system PCR (ARMS-PCR). Notably, the accuracy of the platform is highly consistent with next-generation sequencing (NGS), as evidenced by Kappa test values surpassing 0.9. By utilizing a conical-pore membrane with optimized porosity for single circulating tumor cell (CTC) enrichment, our platform enables point mutations detection in individual tumor cells, offering potential enhancements in precision and reliability for EGFR mutation analysis. This novel methodology holds potential for more accurate and personalized cancer treatment strategies.