Description:
Reference #: 01290
The University of South Carolina is offering licensing opportunities for Graphene Field Effect Transistors for Detection of Potassium Ions
Background:
Sensors based on graphene are currently of strong technological interest in chemical, electrical, environmental, and biosensing applications since adsorbed molecules can readily affect its conductivity through charge transfer. Graphene, being essentially a surface, is extremely sensitive to changes in surface charge, or interaction with ionic adsorbates, presenting itself as an excellent material to develop ion sensitive field effect transistors (ISFETs). The vast majority of the ISFETs demonstrated so far focus on the detection of H+ ions utilizing various surface functionalization layers. Although somewhat more challenging, due to the requirement of selective functionalization layers, detection of metal ions (especially those of alkali metals such as lithium, sodium, potassium, etc. and alkaline earth metals such as magnesium, calcium, etc.) are of high significance due to their important role in cell physiological processes. Meanwhile, detection of transition metal ions (such as those of cadmium) can be useful in environmental toxicology applications. A need exists for an improved ISFET that is stabile yet that still exhibits high selectivity for the ion that the ISFET is designed to detect. The inventors have found that graphene offers an excellent opportunity to address limitations of current Si-based ion sensors, in that graphene provides a surface that is impervious to ions.
Invention Description:
For this invention, graphene chips were synthesized and coated with a polymer membrane making the graphene sensitive to potassium ions. The graphene device was used to measure low concentrations of potassium, but was not sensitive to sodium or calcium ions.
Potential Applications:
In the immediate future the device will be used in cell culture to measure the movement of potassium ions out of cardiac cells and neurons. In the longer term the device could be optimized for implantation in animals and used for detecting cardiac ischemia and neurological disorders such as epilepsy.
Advantages and Benefits:
• Low cost
• Versatility in application; bio-compatible, bio-implantable
• Highly sensitive and selective for potassium ions