Integrated Approach from Sample-to-Answer for Grapevine Varietal Identification on a Portable Graphene Sensor Chip.

Area of Science:

• Materials Science
• Biotechnology
• Analytical Chemistry

Background:

• Grapevine varietal identification is crucial for enology and wine authenticity.
• Complex matrices and low DNA content pose challenges for traditional analysis.
• Graphene-based DNA detection offers a pathway toward ultrasensitive analysis.

Purpose of the Study:

• To develop a DNA-based analytic tool for grapevine varietal discrimination.
• To demonstrate the utility of monolayer graphene in a portable biosensor for DNA detection.
• To achieve ultrasensitive and specific detection of DNA for wine authenticity.

Main Methods:

• Utilized a monolayer graphene field-effect transistor array biosensor.
• Functionalized graphene for DNA immobilization and detection.
• Employed liquid gating and a miniaturized electronic readout for operation.
• Integrated specific DNA probes for varietal discrimination.

Main Results:

• Achieved single-base resolution DNA detection with monolayer graphene.
• Demonstrated high specificity in distinguishing closely related grapevine varieties, including single-nucleotide polymorphisms.
• Reported an attomolar detection limit (∼0.19 aM) and a wide dynamic range (1 aM to 0.1 nM).
• Developed a portable, wafer-scale fabricated graphene chip for DNA analysis.

Conclusions:

• The graphene-based biosensor is a promising tool for grapevine varietal discrimination.
• The platform enables ultrasensitive and specific DNA detection, crucial for wine authenticity.
• This technology supports decentralized analytical tools for the agro-food industry and digitalization.