Ultrasensitive amperometric determination of hand, foot and mouth disease based on gold nanoflower modified microelectrode

Given the widespread use of point-of-care testing for diagnosis of disease, micro-scale electrochemical deoxyribonucleic acid (DNA) biosensors have become a promising area of research owing to its fast mass transfer, high current density and rapid response. In this study, a gold nanoparticles modified gold microelectrode (AuNPs/ Au-Me) was constructed to determine the hand, foot and mouth disease (HFMD)-related gene. The noble metal nanoparticles modification yielded ca. 7.4-fold increase in electroactive surface area of microelectrode, and the signal for HFMD-related gene was largely magnified. Under optimal conditions, the biosensor exhibited salient selectivity and sensitivity with a low detection limit of 0.3 fM (S/N = 3), which is sufficient for clinical diagnosis of HFMD. Additionally, the developed AuNPs/Au-Me was successfully applied to determining the polymerase chain reaction (PCR) amplified products of target gene. Thus, the electrochemical DNA biosensor possesses great potential in early-stage diagnosis and long-term monitoring of various disease.

Automated summary

Due to its fast mass transfer, high current density and rapid response, micro-scale electrochemical DNA biosensors have become a promising area of research in the widespread use of point-of-care testing for diagnosis of disease. In this study, a gold nanoparticles modified gold microelectrode (AuNPs/ Au-Me) was developed to detect the hand, foot and mouth disease (HFMD)-related gene. The modification with noble metal nanoparticles significantly increased the electroactive surface area of the microelectrode and magnified the signal for HFMD-related gene. Under optimal conditions, the biosensor showed excellent selectivity and sensitivity with a low detection limit of 0.3 fM (S/N = 3), which is sufficient for clinical diagnosis of HFMD. Additionally, the developed AuNPs/Au-Me successfully detected the polymerase chain reaction (PCR) amplified products of the target gene. Therefore, the electrochemical DNA biosensor has great potential in early-stage diagnosis and long-term monitoring of various diseases.