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. [Display omitted] • A micro-scale electrochemical DNA biosensor for sensitive determination of hand, foot and mouth disease is constructed. • The AuNPs/Au–Me exhibits excellent sensitivity for detection of disease-related gene with a detection limit of 0.3 fM. • The practicability of this biosensor is well proven by determining PCR products of hand, foot and mouth disease. • The AuNPs/Au–Me biosensor has superior capacity for rapid and sensitive disease diagnosis and monitoring. [ABSTRACT FROM AUTHOR]