[analog31]

In the past, the pharmaceutical companies were big enough to serve as the pot of gold at the end of the rainbow for these startups. Now Apple. On separate occasions, I've met two people who tried this, in two different start-ups, though it was a different kind of spectroscopy in each case.

The challenge is, there's no a priori proof that a method can't work, because the information you need to make that assertion has to come from the same kind of research as trying to make it work. So far the start-ups have all failed in the same way, which is that a signal that looks promising in a test tube can't be reliably distinguished from the myriad sources of variation in the living system.

Note that I'm not in any way discouraging the work, just offering some historical context for the problem space.