The major medical diagnostic companies had been working on microfluidic assays for a couple of decades before Holmes came along. It's a very difficult subject especially when it comes to immunoassays. This wasn't a blue sky field by any means.

There were numerous research papers on the topic, and some time spent with experts in the field would have also pointed her in the direction of the current research.

Almost too late she hired an expert from Abbott Diagnostics (who headed up a number of successful system projects for them), and he walked away after 6 months.

I am no expert, but it's my understanding that blood in the capillaries (fingertip) is not exactly the same as blood in the veins.

> In addition, the small volumes involved and the variability in sample quality based on puncture site and technique make capillary sampling particularly susceptible to errors during the pre-preanalytical phase, which are beyond the control of clinical laboratory personnel

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4622200/

It's not the same as the veins, and varies a lot between fingers and location.

It is well known to any diabetic, or to anyone who played for a few minutes with a blood glucose monitor.