Detection of point mutation in the p53 gene using a peptide nucleic acid biosensor

Abstract A 17-mer peptide nucleic acid (PNA) is used as the recognition layer of an electrochemical biosensor for detecting a specific mutation in the p 53 gene. The performance of the PNA-derived biosensor is compared with that of its DNA counterpart. The significantly higher specificity of the PNA probe greatly improves the detection of a single point mutation, found in many types of cancer. Factors influencing the surface immobilization of the PNA probe, its hybridization to the p 53 target sequence, and the chronopotentiometric detection step, are explored and optimized. This and similar developments hold promise for the diagnosis and management of cancer.