For the analysis of ascorbic acid, amino columns or silica columns are usually used. Analysis using amino columns is particularly wide spread because isoascorbic acid (erythorbic acid) as well as ascorbic acid can be analyzed simultaneously. However, conventional silica-based amino columns are not chemically stable, therefore, they have certain disadvantage such as a decrease in retention and short column life. Since Asahipak NH2P-50 4E is a polymer-based column, it does not suffer from such disadvantages. Moreover, since NH2P-50 column can be washed with alkaline solvents, the column life can be extended.

[Note] This analysis requires column equilibration.
For column equilibration: First introduce 60 mM Phosphoric acid aq. at 0.5 mL/min for 2 hours, and then switch to the eluent.


Sample : 5 μg/mL each, 10 μL
1. Erythorbic acid
2. L-Ascorbic acid

Column       : Shodex Asahipak NH2P-50 4E (4.6 mm I.D. x 250 mm)
Eluent       : 20 mM NaH2PO4+30 mM H3PO4 aq./CH3CN=20/80
Flow rate    : 1.0 mL/min
Detector     : UV (254 nm)
Column temp. : 35 °C