What characteristics might make up an ideal base sensing material? Many believe one of the pre-requisites is surface to volume ratio – how much of the material’s mass is available to be exposed to the desired sensing area. The consensus seems to be thinner is better. How about conductivity? Once the signal is sensed, at what speed can that signal be completely transmitted? Then, it would be preferred if this base sensing material were also strong, flexible, transparent, a barrier material and available in abundance.
Only a decade ago, the opportunity to discover such a material that fits this description might have sounded like a pipe-dream or been something of a leap too far into the future. However, this future is now here, with a material proven to work and currently being designed and tested for many advanced sensing applications. The base sensing material in question is pure carbon in the form of monolayer graphene and the science for graphene sensors is well advanced. Only engineering work remains for this material to be applied to many micro sensing schemas across industry.
“Graphene is an ideal material for sensors. Every atom in graphene is exposed to its environment allowing it to sense changes in its surroundings. For chemical sensors, the goal is to be able to detect just one molecule of a potentially dangerous or indicative substance. Graphene now allows for the creation of micrometer-size sensors capable of detecting individual events on a molecular level”. University of Manchester website, “Graphene, Learn, Applications, Sensors”
Performance Key of Graphene Sensors
Coming in at only a single atom in thickness, advanced graphene sensors can allow the detection and transmission of the signal of any perturbation in its electron flow, with a capability currently unmatched. No other known base material can measure up to the sensing performance, ease of handling and immediate abundance of the monolayer carbon structure that a graphene sensor is comprised of.
Even the smallest micro behaviors or changes, right down to the atomic level, can be detected with a robust and usable signal. Extreme sensing such as needed for DNA sequencing or the binding activity of blending molecules for new drug discovery is now enabled, sending clear and actionable signals each time a new molecule is added to an existing one.
Graphene sensors are even known to measure the contractile strength of individual heart cells called ‘cardio myocytes’. When stimulated, these individual heart cells ‘beat’ like human heart. Previously, the only way to measure the pulse of these cells was to optically observe them and count the frequency of their contractions. Now, cardio-toxicologists can measure the strength of the ‘beat’ of each cell while simultaneously observing it optically, generating an entirely new measurement parameter for that field.