it's not theoretically possible, due to the statistics of small numbers. You can resolve the nanotainer problem by collecting many of them, but by the time you can measure a statistical difference, you might as well have collected a large volume of blood in the first place.

I agree that analyzing small volumes of blood is theoretically possible , but afaik it's yet unclear that you can get good samples from blood drawn from fingers, because it's mixed with interstitial fluid.

(Oh, and massive financial shenanigans.)