HPLC Method for the Determination of Acetaminophen, Phenylephrine, and Ascorbic Acid on Zodiac HST S2 Column

Acetaminophen (paracetamol), a widely used pain reliever, ascorbic acid (Vitamin C), essential for tissue repair and enzymatic function, and phenylephrine, a common decongestant, can all be effectively separated using the Zodiac HST S2 column. This normal-phase HILIC method employs a mobile phase of water and acetonitrile (MeCN) with ammonium acetate buffer. The compounds are monitored by UV detection at 270 nm. Buffer concentration adjustment allows fine-tuning of retention and even reversal of elution order between phenylephrine and ascorbic acid. The method is compatible with mass spectrometry and suitable for pharmaceutical and clinical analysis.