Graphene is one of the strongest, thinnest, and most incredible materials ever invented, and now scientists have used it to build valuable biosensors.

Label-free biosensors are a relatively new medical development, and are used to detect low concentrations of biologically significant molecular substances such as DNA and bacteria and study their chemical properties, Moscow Institute of Physics and Technology reported. The devices eliminate the need for fluorescent or radioactive labels, making experiments easier to conduct and more accurate. The devices have applications in "pharmaceutical and scientific research, medical diagnostics, food quality control and the detection of toxins."

Most of todays biosensor chips are expensive, and composed of a glass substrate, thin gold film and a linking layer for the adsorption of biomolecules. They are generally based on based on the use of surface plasmon resonance (SPR) spectroscopy.  This new patent from Aleksey Arsenin and Yury Stebunov proposes an alternative based on surface plasmon resonance. In this process, graphene or graphene oxide can be used as a linking layer between metal film and a biological layer of molecule targets.

Experiments demonstrated these new biosensors are more sensitive than conventional models and can be used multiple times, which significantly reduces their cost. Using SPR spectroscopy will also widen the scope of pharmaceutical biodetection. Today's biosensors are limited to analyzing biological products based on large molecules, but almost half of all drugs produced by pharmaceutical companies have a low molecular weight. This new development will allow scientists to look at the interactions between targets and small molecules, potentially leading to the development of new drugs.

The findings were published in a recent edition of the journal ACS Applied Materials & Interfaces.