HPLC Separation of NyQuil Active Ingredients

NyQuil is a cough medication produced by Procter&Gamble. It consists of acetaminophen, pseudoephedrine, doxylamine and dextromethorphan. Most of the analytical HPLC methods include either use of ion-pairing reagent or a gradient elution. Mixed-mode chromatography allows to replace long gradient method with short isocratic method. All four compounds are well separated within 3-5 minutes. Methods can be optimized for analysis of other cough composition containing general cough suppressants and pain killers. Method is robust and being validated at several drug companies.


Column Primesep C, 4.6×50 mm, 5 µm, 100A
Mobile Phase MeCN
Buffer TEAPh
Flow Rate 1.0 ml/min
Detection UV, 210 nm




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

Application Column

Primesep C

The Primesep family of mixed-mode columns offers a wide variety of stationary phases, boasting unprecedented selectivity in the separation of a broad array of chemical compounds across multiple applications. Corresponding Primesep guard columns, available with all stationary phases, do not require holders. SIELC provides a method development service available to all customers. Inquire about our specially-tailored custom LC-phases for specific separations.

Select options
Application Analytes:
Acetaminophen (Paracetamol)
Pseudoephedrine (PSE)

Application Detection:
UV Detection
SIELC Technologies usually develops more than one method for each compound. Therefore, this particular method may not be the best available method from our portfolio for your specific application. Before you decide to implement this method in your research, please send us an email to research@sielc.com so we can ensure you get optimal results for your compound/s of interest.