Leiden Researchers Develop Graphene-Based Method for Faster, More Accurate DNA Sequencing

A breakthrough graphene-based method could revolutionize DNA sequencing, making it faster, more affordable, and more accurate. A team of Leiden physicists and chemists has secured EUR 1.2 million in funding through the Dutch Research Council (NWO) Open Technology programme to validate their innovative approach.

A Quantum Leap in DNA Sequencing

The new DNA sequencing method builds on a previous discovery by the research groups of chemist Grégory Schneider and physicist Jan van Ruitenbeek. Their work demonstrated that an electrical current could jump across two atom-thick layers of graphene when positioned at a precise angle—a quantum mechanical phenomenon known as tunneling. Electrons leap between the layers without direct contact, a principle they now aim to harness for DNA sequencing.

How It Works

By slightly separating the two graphene layers, tunneling ceases—unless a molecule, such as a nucleotide, passes between them. ‘When a molecule enters the gap, the tunneling process is reactivated, allowing us to analyze the molecule’s characteristics,’ Schneider explains.

DNA sequencing relies on detecting the four nucleotide bases: adenine (A), cytosine (C), guanine (G), and thymine (T). ‘As a DNA strand moves between the graphene layers, we anticipate being able to identify each nucleotide by measuring the current fluctuations at the exact moment it passes through,’ Ruitenbeek adds. This method could provide a precise and efficient way to sequence DNA.

Advancing Accuracy and Sensitivity

Current DNA sequencing technologies, such as nanopore sequencing, primarily detect differences in size between nucleotides. However, when two nucleotides of the same size but different chemical compositions pass through a nanopore simultaneously, they produce identical signals, limiting accuracy. The Leiden team expects their tunneling-based method to distinguish nucleotides by detecting distinct electronic signatures, overcoming this challenge.

While they have promising theories on how to guide DNA molecules between the graphene layers, the researchers must now demonstrate that their method works in practice. The newly acquired funding will support their efforts to confirm the feasibility of the approach and refine the ability to differentiate between the four nucleotides.

Applications Beyond DNA Sequencing

The potential impact of this research extends far beyond genomics. If successful, this method could be used in various fields, from medical diagnostics to environmental monitoring and even forensic science. Faster and more precise DNA sequencing could accelerate disease research and improve genetic screening.

Beyond healthcare, there is interest from regulatory agencies, such as customs officials at airports, who could use this technology to detect illegal trafficking of endangered species based on DNA traces. Similarly, it could be applied in food safety, allowing for the rapid detection of gases that accelerate food spoilage in transport containers. ‘Wherever there is a need to detect molecules at extremely low concentrations—down to a single molecule—this method could be a game-changer,’ Schneider concludes.

Strengthening Leiden’s Position in Scientific Innovation

As a hub for cutting-edge research, the Leiden Bio Science Park fosters scientific breakthroughs with real-world applications. This graphene-based DNA sequencing method underscores Leiden’s position as a leader in physics, chemistry, and life sciences. With continued support for such pioneering projects, Leiden remains at the forefront of innovation, driving advances that benefit science, industry, and society alike.