Graphene chip shows DNA mutation detection capability

A new biosensor chip for detecting DNA mutations has been created by engineers at the University of California – San Diego.

The chip consists of a DNA probe – an engineered piece of double-stranded DNA containing a sequence coding for a specific type of single nucleotide polymorphism (SNP) – embedded on a graphene field effect transistor.

SNPs are variations of single nucleotide bases in the DNA sequence. While most have no effect on health, some are associated with conditions such as cancer, diabetes, heart disease, neurodegenerative disorders, and autoimmune and inflammatory diseases.

The chip is engineered and fabricated to capture DNA or RNA molecules with specific mutations and produce an electrical signal, which can then be transmitted wirelessly to a mobile device such as a smartphone or laptop.

Current SNP detection methods are relatively slow and expensive, and require specific advanced devices. Once this new technology can be scaled up and wireless capability added, it could offer an innovative solution to this problem.

Ratnesh Lal, professor of bioengineering, mechanical engineering and materials science in the Jacobs School of Engineering at the University of California – San Diego, said: "We are at the forefront of developing a fast and inexpensive digital method to detect gene mutations at high resolution – on the scale of a single nucleotide change in a nucleic acid sequence."