High-performance impedimetric genosensor based on biocompatible TiO2 nanoparticles supported carbon ionic liquid electrode

A high-performance DNA hybridization biosensor was constructed with nanosized TiO2 supported carbon ionic liquid electrode (CILE) as the sensing interface. The morphology of TiO2 nanoparticles and electrochemical performance of the TiO2/CILE were systematically investigated. The decoration of CILE with nanosized TiO2 integrated the advantages of nanosized TiO2 and CILE, including large surface area, excellent conductivity, and fine biocompatibility, which provided a favorable platform for DNA detection. Remarkable change has been observed in the impedance spectra before and after hybridization of probe ssDNA with the target DNA under optimal conditions. The sequence-specific DNA of PML/RARA fusion gene from acute promyelocytic leukemia could be quantified in a wide range of 1.0 × 10−13 to 1.0 × 10−8 mol/L with a detection limit of 2.8 × 10−14 mol/L. The approach does not need oligonucleotide probe or target to be labeled previously, which makes it advantageous in terms of simplicity and noninvasiveness.