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> Ultimately they were foiled by brain-dead regulatory tests that specified blood draw volumes of blood. This regulatory test has to change to accommodate finge

> Ultimately they were foiled by brain-dead regulatory tests that specified blood draw volumes of blood. This regulatory test has to change to accommodate fingerpick volumes of blood; a key feature of microfluidic tests. As I understand it, for many of the tests Theranos was aiming to do there's no real way to achieve it with the tiny volumes of blood they were trying to use: the concentrations of the substance they were testing for were so low the statistical variation of the amount in any given small volume of blood would invalidate the test, even if you could accurately count it.

sradman 6y ago
> for many of the tests Theranos was aiming to do there's no real way to achieve it with the tiny volumes of blood they were trying to use This is exactly the right question to ask. Right from the start we should have had a scorecard of the common lab tests doctors request (under 50 I think). For each test you should ask “is it possible with microfluidics?” and then “has it been combined on a single strip/card yet?” I’m not sure if any concentrations are too low for microfluidics rather than the dilution required to meet the volumes specified in the standardized tests. Are fingerpick volumes too small or are the regulatory tests outdated? The same issue applies to self administered rapid antigen tests during the pandemic. Regulators focused on the “gold standard" PCR tests and ignored the benefit of cheap and easy unamplified tests that can be used in a daily regiment.