Rapid and Ultrasensitive Electrochemical Detection of TP53 Gene Mutation in Blood: Hybridization with a DNA/Gold‐Coated Magnetic Nanoparticle Network

Abstract Mutant TP53 has been demonstrated to be a promising biomarker as it is the most frequently mutated gene in human cancer. However, quantifying TP53 mutation presents two unique challenges: a broad concentration range and ultralow abundance. This study reports on the development of an ultrasensitive and highly‐selective electrochemical biosensor for the rapid detection of TP53 mutation in blood. TP53 mutation analysis is based on a network of gold‐coated magnetic nanoparticles modified with probe DNA (DNA−Au@MNPs). The DNA−Au@MNPs biosensor can rapidly and selectively detect TP53 gene with a single‐base mutation at a high background of wild‐type TP53 gene in blood. Moreover, the sensor presents a broad dynamic range of 1 aM to 10 nM for the mutant TP53 gene with the lowest detected concentration of 1 aM and significantly reduced response time of 20 min. Therefore, this biosensor demonstrates the potential to be used for minimally invasive analysis of cancer.