Detection of DNA hybridization based on SnO2 nanomaterial enhanced fluorescence

In this paper, enhanced fluorescence emissions were firstly investigated based on SnO2 nanomaterial, and its application in the detection of DNA hybridization was also demonstrated. The microarray of SnO2 nanomaterial was fabricated by the vapour phase transport method catalyzed by patterned Au nanoparticles on a silicon substrate. A probe DNA was immobilized on the substrate with patterned SnO2 nanomaterial, respectively, by covalent and non-covalent linking schemes. When a fluorophore labelled target DNA was hybridized with a probe DNA on the substrate, fluorescence emissions were only observed on the surface of SnO2 nanomaterial, which indicated the property of enhancing fluorescence signals from the SnO2 nanomaterial. By comparing the different fluorescence images from covalent and non-covalent linking schemes, the covalent method was confirmed to be more effective for immobilizing a probe DNA. With the combined use of SnO2 nanomaterial and the covalent linking scheme, the target DNA could be detected at a very low concentration of 10 fM. And the stability of SnO2 nanomaterial under the experimental conditions was also compared with silicon nanowires. The findings strongly suggested that SnO2 nanomaterial could be extensively applied in detections of biological samples with enhancing fluorescence property and high stability.