today i am doing calibration of HPLC. when i inject the
blank it was going on -ve.(bleow then zero) why?

Answer Posted / m.kiran reddy

Negative peak simply indicate that your mobile phase
absorbs UV light.So use only HPLC grade solvents.Even with
HPLC grade solvents you get the negative peaks you system
might not be working properly.

Regards
M.KIRAN REDDY

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