Minor Cross-Contamination from slight "Backwash"

Running a protocol produces small droplets as "backwash" into some lines.


This issue has to do with switching between chemicals on the rotary shear valve while having a difference in pressure between the chemical source line and the pump. It could also be an artifact due to the dead volume of gas (i.e: compressible) between the syringe and the rotary shear valve.

There are a few approaches before we can consider this "fixed."
* If we can prevent the primed line from moving altogether when we switch ports on the rotary shear valve, that's ideal.
* If we can remove the residual liquid such that there is no cross contamination but the actual primed line moves slightly, that's ok too.