All these fluids needed to flow through the cartridge in a
meticulously choreographed sequence, so the cartridge contained little
valves that opened and shut at precise intervals. Ed and his engineers
tinkered with the design and the timing of the valves and the speed at
which the various fluids were pumped through the cartridge.
Another problem was preventing all those fluids from leaking and
contaminating one another. They tried changing the shape, length,
and orientation of the tiny channels in the cartridge to minimize the
contamination. They ran countless tests with food coloring to see
where the different colors went and where the contamination
occurred.
It was a complicated, interconnected system compressed into a
small space. One of Ed’s engineers had an analogy for it: it was like a
web of rubber bands. Pulling on one would inevitably stretch several of
the others.
Each cartridge cost upward of two hundred dollars to make and
could only be used once. They were testing hundreds of them a week.
Elizabeth had purchased a $2 million automated packaging line in
anticipation of the day they could start shipping them, but that day
seemed far off. Having already blown through its first $6 million,
Theranos had raised another $9 million in a second funding round to
replenish its coffers.
The chemistry work was handled by a separate group made up of
biochemists. The collaboration between that group and Ed’s group was
far from optimal. Both reported up to Elizabeth but weren’t
encouraged to communicate with each other. Elizabeth liked to keep
information compartmentalized so that only she had the full picture of
the system’s development.
As a result, Ed wasn’t sure if the problems they were encountering
were due to the microfluidics he was responsible for or the chemistry
work he had nothing to do with. He knew one thing, though: they’d
have a much better chance of success if Elizabeth allowed them to use
more blood. But she wouldn’t hear of it.