Scalable production of high sensitivity, label-free DNA biosensors based on back-gated graphene field-effect transistors

摘要

Scalable production of all-electronic DNA biosensors with high sensitivityand selectivity is a critical enabling step for research and applicationsassociated with detection of DNA hybridization. We have developed a scalableand very reproducible (> 90% yield) fabrication process for label-free DNAbiosensors based upon graphene field effect transistors (GFETs) functionalizedwith single-stranded probe DNA. The shift of the GFET sensor Dirac pointvoltage varied systematically with the concentration of target DNA. Thebiosensors demonstrated a broad analytical range and limit of detection of 1 fMfor 60-mer DNA oligonucleotide. In control experiments with mismatched DNAoligomers, the impact of the mismatch position on the DNA hybridizationstrength was confirmed. This class of highly sensitive DNA biosensors offersthe prospect of detection of DNA hybridization and sequencing in a rapid,inexpensive, and accurate way.