Sam Goody’s technological pivot from vinyl to polycarbonate was one of the most sweeping changes of the guard that the Earth has ever seen. Not only did new optical CDs have the rewritable potential of the magnetic ribbon tape, they also had the nonrewritability of the record. While many imagine a similar takeover of silicon by graphene may be just around the corner, those in the field of biosensing know that we have already rounded the bend. Case in point: Some researchers have now created a graphene sensor that can detect one of the genetic markers of cancer.

The good old graphene exfoliation techniques, where layers of graphene are peeled from graphite, do not generally create enough surface area for a sensitive detector. Even the more exotic graphene fabrication methods, likesupersonic sprays from de Laval nozzles, just make simple uniform coatings. Researchers from Swansea University have now perfected a new graphene processing technique to build a detector of precancerous conditions that blows other technologies out of the water. [doi:10.1088/2053-1583/1/2/025004]. They were able to grow graphene on silicon carbide substrates and then use more germane semiconductor processes to pattern them. Antibodies that could bind to a specific derivative of damaged DNA were then bound using fancy chemistry to functionalize the graphene.

The hallmark of several kinds of cancer is widely believed to be a molecule called 8-hydroxydeoxyguanosine, or simply 8-OHdG. Guanosine is one of the four genetic bases and its damaged hydroxy form ends up in the blood, saliva, and urine as it cycles naturally through the cellulo-physiological circle of life. The new graphene chip was able to detect this molecule at concentration of just 0.1 nanograms per milliliter. That is five times more sensitive and several times faster than any other method we have. This new device shifts the balance of power back to the hardware and puts the onus of relevance back on the plate of biology. In other words, medicine asked for the ability to easily detect 8-OHdG and they got it. Now the larger world can respond to medicine and biology with a resounding, show me that it really matters to my quality of life.

The amount by which your iPhone memory exceeds that of the computers on board the Apollo 11 is the perfect measure for how little the size of your bit matters compared to what you do with it. While the genetic bit that indicates you may have cancer tells you infinitely more than the one that holds the Nth color value of the last pixel in a sunset, the real powers are in the devices that feed that bit. The answer to the actual relevance of myriad and frequently nebulous biomarkers like 8-OHdG is not yet in hand. Devices like the new Swansea graphene chip are exactly what we need to determine if they are mere technological lures, or end goals in themselves.