Electrochemical detection of circulating-free DNA methylation: A new indicator for early cancer screening

This study introduces a novel electrochemical approach for detecting circulating-free DNA (cfDNA) by leveraging distinct methylation patterns characteristic of cfDNA from healthy controls and cancer patients. Our findings reveal that cfDNA from cancer patients exhibits a unique affinity for gold surfaces due to abnormal methylation, which enables its electrochemical differentiation. By using square wave voltammetry (SWV) with optimized parameters, we achieved high sensitivity (0.89) and specificity (0.73) in distinguishing cfDNA from healthy controls and cancer patients. Clinical trials demonstrated the effectiveness of this method, surpassing conventional tumor markers in early cancer screening. SEPTIN9 (SEPT9) methylation is used as an example to demonstrate the generalizability of our method for analyzing DNA methylation changes, which can subsequently be applied to identify the presence of cancer.This approach offers notable advantages, including simplicity, rapid response, and cost-effectiveness. While the current methodology is primarily suited for detecting the presence of cancer, its potential for prognostic and diagnostic applications warrants further investigation.