Scientists from India and Japan have developed a new method for detecting causative genes using graphene-based transistors. Graphene field-effect transistors (GFETs) are capable of detecting virulence genes by DNA hybridization: the conductivity of a transistor changes when the DNA probe binds to its complementary target DNA. Nobutaka Hanagata from Japan's National Institute of Materials Science and his colleagues improved the graphene sensor by attaching DNA probes to the transistors by a drying process, eliminating the need for the expensive and time-consuming coupling agent nucleosides Acid sequence. The research team designed the GFETs to consist of graphene containing a titanium-gold electrode deposited on a silicon substrate, then dropping the DNA probe salt solution onto it and allowing it to dry. They found that this process of drying allowed the DNA probes to be immobilized directly on the graphene surface without any coupling agent. Subsequently, they added a salt solution containing the target DNA to their surface and incubated for 4 hours to hybridize the DNA. Through these processes, GFETs worked successfully. Researchers found that when the probe binds to the target, the conductivity of the sensor changes, which means that the pathogenic target gene is present, while the sensor does not change its conductivity when using other non-complementary genes. DNA hybridization can be detected by binding fluorescent molecules to the target DNA, in which case the sensor glows in the event of hybridization. However, this method involves a complicated labeling process, and also requires an expensive detector to detect fluorescence. GFERs, however, are a cheaper, easier to use and more sensitive option for detecting disease genes. "Next, we will further optimize the function of GFETs for the future of biosensors, especially in the detection of genetic diseases," the researchers concluded in an article in Science and Technology of Advanced Materials.