Cetylpyridinium Methods with Good Efficiency and Peak Symmetry
Primesep B separates tertiary amines, such as cetylpyridinium with symmetrical peak shape by a combination of reversed-phase and ion-exclusion mechanisms. The embedded basic functional group on the stationary phase shields the underlying silanols to prevent peak tailing. Retention time can be changed by changing either organic content or acid content in the mobile phase. C18 reversed-phase columns do not typically show this tuning ability with acid content. Excellent peak shape results with a mass spec compatible mobile phase of water, acetonitrile (MeCN, ACN) and trifluoracetic acid (TFA) with UV detection at 250 nm.
Surfactants are molecules that contain both hydrophilic and hydrophobic groups, usually in the form of a hydrophilic head and a hydrophobic tail. Surfactants are used in detergents where they can form micelles around hydrophobic dirt molecules and wash them away. Triton X-100 is a surfactant with a hydrophilic polyethylene oxide chain that can be separated on a Primesep D reverse-phase HPLC column based on the number of oxide units in the chain. The mobile phase is water, acetonitrile (MeCN, ACN) and sulfuric acid as buffer. UV detection at 210nm.
HPLC Separation of Cetylpyridinium Chloride and Triethylene Glycol
Cetylpyridinium chloride is hydrophobic basic compound and triethylene glycol is hydrophilic neutral compounds. Quantitative analysis of both compounds is problematic due to a different nature of these two analytes. Both compounds were analyzed on an Obelisc N column in HILIC/cation-exchange mode. Cetylpyridinium chloride is retained by cation-exchange mechanism, and triethylene glycol is retained by HILIC mechanism. Mixed-mode HILIC approach allows to retain compounds either based on multiple or single mechanisms interaction, thus providing a valuable approach for analysis. Cetylpyridinium chloride and triethylene glycol can be monitored by combination of UV and ELSD/CAD.