Nanoelectric device could lead to a diagnostic blood test for ME/CFS (Simon McGrath blog)

Nanoelectric device could lead to a diagnostic blood test for ME/CFS

Last week, Dr Ron Davis’s team published a pilot study showing remarkable results for their nanoneedle device. Strikingly, there was no overlap between the results for 20 ME/CFS patients and those for 20 healthy controls, something that is almost never seen with this illness.

A nanoelectronics-blood-based diagnostic biomarker for myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS)
R Esfandyarpour, A Kashi, M Nemat-Gorgani, J Wilhelmy and RW Davis. 2019

The nanoelectric blood test

Nanoelectric silicon wafer that researchers use to test samples. Black lines are not part of the wafer. (Figure 2C from the paper)
The research used nanomanufacturing techniques to embed large numbers of tiny electrodes within a silicon wafer. Each electrode, or nanoneedle, is comparable in size to a cell.

The researchers created a simplified blood sample for each patient that consisted of white blood cells (immune cells) in plasma, but without red blood cells and platelets. The scientists added each sample to a silicon wafer, and the electrodes then measured electrical impedance.

Impedance is a measure of how difficult it is for the electrical current to pass through the cells and/or plasma next to the electrodes. Critically, in the nanoelectric set-up, the authors say that change in impedance “results from cellular and molecular interactions”.

The key element of the test, which exposes the dramatic difference between patient and control samples, is to force the cells to use more energy than normal. The aim was to replicate at the cellular level a key aspect of ME/CFS: the way problems emerge when energy demands ramp up.

The researchers forced the cells to use more energy simply by adding sodium chloride — table salt — to the sample. In the jargon, the salt acts as a “hyperosmotic stressor”.

Some of the extra salt enters the cell and, through osmotic pressure, the salt draws water with it, causing the cell to swell up. The cell has to combat this tendency and so must use energy to power a molecular pump that pushes the extra salt back out of the cell.

The different response seen between the samples of patients and controls is striking. There is little change in electrical impedance for healthy cells. But after half an hour or so, there’s a huge increase in impedance for the samples from ME/CFS patients.

Read the full blog​

 

I like the yellow band of daylight!
I hope they can continue, funds-wise.