Hi guys. I´m looking for a metabisulfite analysis by HPLC or UHPLC in a cream. Possible detectors are DAD, RI and Fluorescence.
Recently I was trying to react metabisulfite with benzaldehyde to form an aldehyde-bisulfite adduct. I can see benzaldehyde, but not the adduct, by DAD. And I think reaction is happening because benzaldehyde peak gets lower. Perhaps I cannot see adduct by UV. May be Fluorescence will work? Which lambda emm and exc?
Anyone knows another good method by HPLC? Need to be retained because placebo got lots of peaks (including actives and parabens).