Archer Materials develops liquid-gated graphene field effect transistor for use in medical diagnostics

Archer Materials (ASX: AXE) has achieved a long-term biochip technology development goal of fabricating an operational liquid-gated graphene field effect transistor (gFET).

The gFET device is a sensing component which will be used for digitising biologically-relevant signals such as those from target analytes of viruses or bacteria.

It is a foundational feature of Archer’s ‘lab-on-a-chip’ biochip technology which is designed to enable the complex detection of some of the world’s most deadly communicable diseases.

The company aims to integrate the gFET into advanced microfluidic systems to create miniaturised lab-on-a-chip device platforms for use in medical diagnostics.

It has been specially fabricated to prevent liquids from shorting the integrated circuit, while simultaneously obtaining electronic signals using liquid as part of the device.

Archer said the gFET could potentially enable multiplexing, which is the ability to parallelise the detection of multiple biologically-relevant targets in droplet-sized liquid samples on a chip.

The innovation offers an ultrasensitive approach to analyte detection over conventional electronic sensors used in current lab-on-a-chip devices.

Technological progress

Archer has made significant technological progress over the last year in the lead-up to the liquid-gated gFET.

The company’s advanced lithography was used to integrate a single-atom-thick sheet of graphene in silicon electronics, while hair-thin microfluidic channels have been fabricated on a silicon wafer for sample processing and transportation to smaller built-in sensors for analysing biochemical targets.

The company has also engineered biochemical reactions with the potential for on-chip detection and quantification of specific DNA or RNA fragments relevant to viruses and bacteria.

In other technological achievements, Archer’s foundry has fabricated a magnitude of component feature sizes reaching sub-10 nanometres on a silicon wafer which would potentially allow for high performance sensing.

Significant step forward

Archer chief executive officer Dr Mohammad Choucair said the gFET innovation was a significant step forward for the materials technology company.

“Our graphene-based transistor consists of a single-atom-thick sheet of graphene to act as an ultrasensitive sensor intended to operate alongside other bio-functional regions fabricated on the same miniaturised chip,” he said.

“The work is an exciting development towards realising an operational biochip technology at Archer.”

Advanced material

Graphene is an advanced material with electronic, chemical and physical properties on the nanoscale which benefit its use in field effect transistors for biosensing applications.

Key advantages include easy operation, fast response times, real-time monitoring, high specificity and sensitivity, microfluidic integration and multiplexing capability.

The properties of graphene have been well-studied scientifically in the field for over 15 years.