Facile and sensitive paper-based chemiluminescence DNA biosensor using carbon dots dotted nanoporous gold signal amplification label

Abstract

A facile and sensitive chemiluminescence (CL) protocol for the detection of DNA on low-cost paper analytical device using simple, rapid wax-screen-printing method was developed by combining simply covalent modification and signal amplification in this work. The DNA sensor was prepared with N,N′-disuccinimidyl carbonate (DSC) to capture DNA by covalently immobilizing on μPADs, and carbon dots (C-dots) dotted nanoporous gold (C-dots@NPG) was employed for signal amplification label. After the sandwich-type DNA hybridization reaction, C-dots@NPG labeled signal DNA was captured on the DNA biosensor. In the presence of potassium permanganate, the radiative recombination of oxidant injected holes and electrons generated oxidant induced CL reaction of the C-dots@NPG and produced the CL signals. Under optimal conditions, the application of this paper-based DNA sensor was successfully performed with a linear range of 10⁻¹⁸ to 10⁻¹⁴ M and with a detection limit of 8.56 × 10⁻¹⁹ M for target DNA. The newly designed strategy not only provides a simple DSC modified platform to improve the immobilization of capture DNA or antibody, but also offers a high-efficiency C-dots@NPG signal amplification label to enhance the sensitivity, and thus will be a promising potential in public health and environmental monitoring.