Sudden increase in signal intenisty (fluorescence detection)

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Hi,

We replaced the lamp for our Shimadzu fluorescence detector (attached to Nexera serier pump system). First day the signal for tocopherols was rather constant, but slightly lower than with the old lamp. After the first batch was run, instrument was shut down for the night. Next day, the signal was suddenly approx. 10 x higher in terms of peak areas. Methods used, injection volume and the eluent (heptane) were the same.

What could be the explanation for thie sudden increase? Something to do with "running-in" of the new lamp?
I saw similar on an Agilent FLD G1321 running methanol. I could see the baseline dropped substantially flushing low flow overnight, also between solvent lots. This was not an auto zeroing detector so I was able to see baseline value. Do you show same baseline values, if not auto zeroing?
2 posts Page 1 of 1

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