I run size exclusion chromatography. The pressure applied across the chromatograph, responsible for inducing the flow of the mobile phase, is roughly 94 bar, provided by a pump. The chromatograph is filled with thousands of 4 micron beads with pores in them. I have noticed that the chromatograph loses its ability to distinctly separate certain components after a while if run the fluid through the device by increasing the flow rapidly from 0 to X, as opposed to slowly ramping the pressure (and therefore, the flow rate) to X. If I do the former, the tubes need to be replaced every two weeks. If I do the later, the need to be replaced every three months. My question is, what precisely is causing this? Is the rapid pressurization dislodging the beads somehow? Is it completely tearing them apart by rupturing the pores? I intuitively understand 'X force fast = bad' and 'X force slowly, over time = good', but I want to understand precisely what is happening to the chromatograph that is causing it to lose its precision.

  • $\begingroup$ An engineer at the chromatograph company might be able to help. $\endgroup$ – mmesser314 Dec 4 '19 at 2:23

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