Chromatography Forum

Hello,
I have trouble with the baseline.
I think may be linked to dirty cell flow of UV detector.
Someone may indicate an effective method for cleaning?
Thanks for the help

Depends on your previous analyses. But regulary, small flow (e.g. 0.2mL/min) of warm water over night or mixture of water and isopropanol could fix your problem.

Regards

If it's very diry I have clean the inside with HNO3. Draw it into the cell with a syringe, let it soak for a couple of minuts, then push it out again with the syringe. Then rinse with plenty of clean water!!

It is important to make sure everything that comes in contact with the liquid can resist acid at least for the amount of time you have the HNO3 inside the cell or you will ruin the cell.

Depending on the detector it's possible to remove the quartz compartment from the flowcell assembly. If so, then you can soak only the quartz part in HNO3.

If you don't or can't use this rather harsh cleaning treatment, then pump IPA into the cell, leave it there for a couple of hours, then pump clean water through. This will take most comraminants from a flow cell..

If possible it might be advantageous to do a self check on the detector to verify that a dirty cell is the culprit.

I remember that the engineer from shimadzu once told me when the quarze cell are removed the corresponding washes should be replaced when reinstall the quarze cell! Am I right?

If you disassemble any cell, then you must use new washers or seals, if that's what you mean.

You might want to also check the lamp energy. See whether it conforms to Shimadzu's specifications.

Which detector and mosdel you have? For example ChemStation have detector cell test.