Soft Drink Containing Vitamin C (NH2P-50 4E)

Vitamin C in the soft drink was analyzed using Asahipak NH2P-50 4E.

[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 pretreatment)
1. Add 5 % methaphosphoric acid aq. to make up 30 mL sample solution.
2. Filtrate using a 0.45 μm disposable filter.
3. Just before the injection into HPLC, add purified water to make 10-fold solution.
(The concentration of methaphosphoric acid should be 0.5 % or lower.)

Column       : Shodex Asahipak NH2P-50 4E (4.6 mm I.D. x 250 mm)
Eluent       : 20 mM NaH2PO4 + 30 mM H3PO4 (pH2.2)/CH3CN=20/80
Flow rate    : 1.0 mL/min
Detector     : UV (254 nm)
Column temp. : 35 ℃