[ChrisLomont]

You're wrong; a single red blood cell is several femtoliters. To get a good statistical count of much more rare (yet important) features one can sample much, much more than this and still get anomalies from having too small a sample.

Here's [1] a cool graphic showing the tip of the iceberg.

[1] https://en.wikipedia.org/wiki/File:Reference_ranges_for_bloo...

[lvs]

No, I'm not wrong. You're talking about testing for cell counts, which is not -- as I understand it -- what this company was approved to do. For molecular and protein components of blood on the nanomolar range, you would not encounter this problem until you were sampling in the femtoliter regime. Just use Avogadro's number, and you'll get it.

[Fede_V]

A lot of those molecules are bound up in cells, they are not freely diffusing in blood. Even those diffusing in blood are not uniformly distributed, blood is highly dishomogeneous.

[lvs]

Routine metabolic paneling and serology does test for molecules that are uniformly distributed in blood. I can't say it any plainer than that. Of course many possible testing targets are inside cells, but these tests were not claiming to look at any intracellular targets, at least as far as I know.

[learc83]

They weren't really clear about what tests they could perform with their technology, but they did say they planned on offering the "full range" of blood tests.