Troubleshooting ascorbic acid

Discussions about HPLC, CE, TLC, SFC, and other "liquid phase" separation techniques.

4 posts Page 1 of 1
Hello everyone,

I am quantifying ascorbic acid in pharmaceuticals with a 100% aqueous mobile phase, pH 2.6 adjusted with acetic acid.

During the first 5 injections of standard solution, peak area increases 4-fold, then stabilizes, which has no obvious explanation...

Can anyone help? Could this be a matter of column equilibration or dilution solvent?
Hello.
Ascorbic acid UV-spectrum (and peak area too) rely heavily on mobile phase pH so it may be column equilibration.
Depending on injection volume and mobile phase buffer capacity it may be solution pH too.
Best regards,
Dmitriy A. Perlow
I will try longer column equilibration time, I will decrease injection volume and let's see what happens...

Thank you!
Also , consider changing rotor seal of your injector.
4 posts Page 1 of 1

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