A universal constructing method for high performance DNA biosensors based on the optimized photoelectrode material and dual recycling amplification

Abstract

Many effective strategies for photoelectrochemical DNA sensors have been developed in the past decades. Most of them focused on the detection performance including sensitivity, limit of detection and linear range, but few on the pivotal roles of photoelectrode materials and the universality for strategies. Herein, the photoelectrode material was optimized by density functional theory for improving the comprehensive performances of DNA biosensor for the first time. And the universal strategies, based on dual recycling amplification, was discussed by different nucleic acid sequences. After systematical optimization of detection conditions, a large linear range of 10-16 to 10-6 M, high sensitivity of 5.66 μA·cm−2·dec-1 and low limit of detection of 10-18 M (a gene copy per microliter) were achieved for the detection of DNA sequences from the I27L gene. Finally, detection of DNA sequences from Orientia tsutsugamushi was used to prove the universality of the novel method.