Ultrasensitive electrochemiluminescence detection of p53 gene by a novel cloth-based microfluidic biosensor with luminol-gold nanoparticles and hybridization chain reaction amplification

Abstract

A dual-signal-amplified cloth-based ECL biosensor has been firstly explored to detect p53 gene, where the luminol functionalized gold nanoparticles (Lu-AuNPs) are used for probe labels and signal amplification, and the hybridization chain reaction (HCR) is further applied to increase the sensitivity of ECL detection. Carbon ink/solid wax-based screen-printing is utilized to manufacture the cloth-based carbon electrodes and sample/auxiliary chambers to construct a collapsible three-dimensional (3-D) cloth-based device. Profiting from the 3-D device feature, it is easy to prepare the sensing interface modified by multi-walled carbon nanotubes. When the target DNA, signal nanoprobes and hydrogen peroxide (H2O2) are successively dropped onto the sensing interface, the Lu/H2O2-based ECL can be operated well. Under optimal conditions, the p53 gene can be desirably detected, with a linear range of 0.0001–1000 pM and detection limit of 0.02 fM. The biosensor has a wider linear range, and relatively high sensitivity, selectivity, stability and reproducibility, possibly because of the excellent constitution of signal nanoprobes and HCR products. Peculiarly, the biosensor has the capacity for p53 gene detection in the complex cellular homogenate samples, and discrimination of one-, two- and even three-base-mismatched p53 DNA sequences. So, it may supply a hopeful method in applications of gene diagnostics.