Separation of NyQuil Active Ingredients on Primesep C

Primesep C separates the active ingredients in the over-the-counter cold medicine, NyQuil. Succinate and bromate co-elute early, but acetaminophen, pseudoephedrine, doxylamine, and dextromethorphan are baseline resolved. A combination of cation exchange, complex formation, and hydrophobic interactions separate this mixture with a mobile phase of water, acetonitrile (MeCN, ACN) and triethylamine (TEA) phosphate with UV detection at 205 nm.


Column Primesep C, 4.6x150 mm, 5 µm, 100A
Mobile Phase MeCN
Buffer TEAPh
Flow Rate 1.0 ml/min
Detection UV, 205 nm


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

Application Analytes:
Acetaminophen (Paracetamol)
Pseudoephedrine (PSE)