Renewable superwettable biochip for miRNA detection

Biochips are a collection of miniaturized test sites (microarrays), which enable researchers to quickly screen large numbers of biological analytes, have become one of the most promising technologies in various biomedical fields. Inspired by self-cleaning property of titanium dioxide (TiO2), a renewable superwettable miRNA biochip (RSMB) was developed for specific and quantitative detection of miRNA-141. The hydrothermal synthesized TiO2 nanowires on the fluorine-doped tin oxide (FTO) were employed as substrate and provided renewable property. Superhydrophilic microwells were spotted on the superhydrophobic TiO2 substrate. Due to the extreme wettability difference between the microwell and surrounding substrate, the analytes could be concentrated and anchored onto the microwells from diluted solutions. Such RSMB could be renewable efficiently via photodegrading the organics on the TiO2 substrate, and consistent results can be obtained after several cycles. This work provided an alternative tool for developing the renewable biochips and shows potential applications in the biomedical diagnosis.