HPLC Separation of Acetaminophen, Phenylephrine, and Diphenhydramine

Primesep C separates acetaminophen (paracetamol), phenylephrine, and diphenhydramine-- common over-the-counter cold and flu medication ingredients such as Tylenol products—by either an acetonitrile or phosphoric acid gradient. The HPLC separation uses a mobile phase of water, acetonitrile (MeCN, ACN), and phosphoric acid with ultraviolet (UV) detection at 210 nm.


Column Primesep C, 4.6x150 mm, 5 µm, 100A
Mobile Phase MeCN
Buffer H3PO4
Flow Rate 1.0 ml/min
Detection UV, 210 nm


Class of Compounds Drug, Analgetic, Acid, Hydrophilic, Ionizable,
Analyzing Compounds Acetaminophen, Pseudoephedrine, Diphenhydramine

Application Analytes:

Acetaminophen (Paracetamol)