HPLC Separation of Coffee Components on Zodiac HST SB Column

The amount of caffeine in both regular and decaffeinated coffee can be accurately measured using the Zodiac HST SB column. This HPLC method utilizes a combination of reversed-phase and polar interactions to separate caffeine without interference from the complex coffee matrix. To enhance method robustness and protect the analytical column, a diverter valve and guard column can be employed. The sample is initially loaded onto the guard column, and after a set time, the flow is reversed to direct only the caffeine peak onto the analytical column, preventing strongly retained late-eluting compounds from reaching and fouling the main column. The separation is performed using a mobile phase consisting of water, methanol (MeOH), and phosphoric acid (H₃PO₄), with UV detection at 270 nm.