HPLC Analysis of Organic Acids in Beverages on Chromolith^® HighResolution RP-18 endcapped

sample preparation

sonicate 5 mL of orange drink for 5 minutes, add 0.2 mL of phosphoric acid solution (1M), dilute to 10 mL with water

column

Chromolith HighResolution RP-18, 10 cm x 4.6 mm I.D., 2 μm particles (1.52022)

mobile phase

10 mM diammonium hydrogen phosphate, pH 2.7

flow rate

1.0 mL/min

pressure

32 bar (464 psi)

column temp.

30 °C

detector

UV, 210 nm

injection

20 μL