Ann: New Biochip gFET test procedure and process developed, page-12

AXE's graphene biosensor chip- finally delved into this to find what unique value proposition AXE is bringing to biosensing with graphene FETs.

before that, some starter facts we know about graphene - it's as tough as nails, but is a film of material that has all its atoms on the surface, ready to sense anything that's dropped on it. it's a well understood feature of graphene, plenty of people using this property for loads of research. Not all gFETs are used for biosensor work which has made some advances for 7 years or so. Drop a liquid onto the graphene, zero bias electrode set up. This relies on the sample reacting with the graphene.

the other way is liquid-gated set ups, which AXE is using. Like all transistors, there is a gate electrode that controls voltage and in this gFET an electrolyte is being used as a contact between the electrode and the graphene surface (sensor) . The electrolyte acts as an amplifier of charge that's detected on the graphene. where AXE can differentiate here is with choice of electrolyte. Latest announcement , they have electrolytes through which they can vary the speed and sensitivity for different uses, different detection tasks.

now 'traditionally' biosensing with graphene involves 'attachment chemistry' - first bind things like single strand DNA strands to the graphene, this probe DNA then attaches to the target DNA that is being tested for ( biophysics is really complex, quantum mechanics seems less so, to me anyway).When a probe detects the target DNA, they bind and that causes a shift in the Dirac voltage which registers as a detection on the readout. So basically the graphene surface binds with biological probes that then find and bind with targets. Believe it or not. Imagine doing this very fiddly (time consuming) stuff for every possible target molecule. Which is what FDA approval demands.

reading this latest announcement, I can see that AXE might be trying to do things differently, less fiddly, less bio probing.How?

Archer determined new ways to electrically operate the gFET sensor – speed, and the directionof the voltage applied to the gate (a part of the transistor). These factors change how thetransistor responds based on the liquid and the number of ions in the liquid (tiny, chargedparticles), ultimately setting the sensitivity and speed of the sensor. Through this ability, Archercan use new ways to detect substances under different operating conditions using data analysisand machine learning.

just measure dirac voltages of different targets via AXE gFET biosensor without needing attachment chemistry steps. Build a voltage profile database of all target biomolecules. Use data analysis to quickly find a particular molecule profile. I would be pretty excited if they could engineer a great graphene surface, a range of electrolytes for gating and significant dirac shifts that leaves no doubt as to a particular successful detection. Any of these achievements will be price sensitive announcements. As fas I can see, there have been no price sensitive announcements for the bio chip since September 2023 when a commercial foundry validated the gFET design. And what that meant was that AXE has got the right workable dimensions of the graphene strip between workable electrode spacing. The 12CQ on the other hand has had price sensitive updates much more often. End of the day AXE needs to offer something that is a no brainer for quicker diagnostics. Multiplexing is not a USP these days. Need to offer very fast, very reliable detection with a small sample and do it without much bio pre processing.