Nano-LC Column Switching - So Easy a Caveman Can Do It

摘要

This column switching system was found to operate with the following characteristics: 1. The 3-slot rotor design reduced the total number of fluidic connections from 27 to 6, simplifying setup and operation. 2. The use of 3 columns and 3 gradient stages (Load, Elute, Wash) allowed 3 samples to be analyzed in 1/3 the time, with an MS duty cycle >95%. 3. Channel-to-channel variation is eliminated with this single pump / single channel implementation. 4. Excellent column-to-column reproducibility was observed with < 30s difference in retention time over a 60 minute gradient. 5. A limitation of this design is that each gradient stage must start and end at (0%B) to prevent organic from being captured in the valve and transferred to an equilibrated column. 6. The use of a pump with a low delay volume would improve the observed (8 min) gradient delays. The volume of the column and rotor is <750 nL.