title: Some effects of replacement of metaphosphoric acid/acetic acid solvent system with trichloroacetic acid in microfluorometric determination of vitamin C.
abstract: Trichloroacetic acid (TCA) is suggested as a substitute for the metaphosphoric acid/acetic acid (HPO3-HOAc) solvent system in the AOAC microfluorometric determination of vitamin C. Comparative advantages of TCA are easier handling, greater stability, and the approximate 10-fold increase in sensitivity. For both solvent systems, the influence of acid concentration on fluorescence is described. TCA provides maximum fluorescence enhancement at pH 5.5-6.0.
mesh_terms: D000085:Acetates; D019342:Acetic Acid; D001205:Ascorbic Acid / Q000032:analysis*; D006863:Hydrogen-Ion Concentration; D007202:Indicators and Reagents; D010757:Phosphorous Acids; D012997:Solvents; D013050:Spectrometry, Fluorescence / Q000379:methods; D014238:Trichloroacetic Acid
chemical_list: D000085:Acetates; D007202:Indicators and Reagents; D010757:Phosphorous Acids; D012997:Solvents; D014238:Trichloroacetic Acid; C043639:metaphosphoric acid; D001205:Ascorbic Acid; D019342:Acetic Acid