Fast HPLC Analysis of Methylamine, Dimethylamine and Trimethylamine on Coresep 100 Mixed-Mode Column
Application description

Methylamine, dimethylamine and trimethylamine are very polar basic compounds with a pKa of about 10.They are used as building blocks in pharma, agricultural and chemical industries. All three are not retained by RP chromatography and have no UV activity. The retention of these amines is only possible in the HILIC mode or with the use of a ion-pairing reagent. We have developed a robust method for the analysis of these simple amines by the reversed-phase cation-exchange mechanism on the Coresep 100 mixed-mode HPLC column. Amines are retained by a weak reversed-phase mechanism and cation-exchange mechanism. Mixed-mode chromatography and columns utilize a small difference in hydrophobic and ionic properties to provide retention for basic and hydrophobic analytes. The retention time and resolution are adjusted with the amount of ACN, buffer pH and buffer concentration. Trifluoroacetic acid in the mobile phase is used for visualization of these volatile non-UV active amines in LESD. Other buffer and additives can be used to accommodate specific detection techniques like CAD, MS and RI.

Conditions of Experiment
Column: Coresep 100
Separation Modes: reversed-phase, cation-exchange
Column Dimenstions: 4.6x150 mm, 2.7 um, 90A
Mobile Phase: 5% ACN with 0.1% TFA
Detection: ELSD, 40°C
Sample: 2 mg/ml
Injection: 3 uL
Flow rate: 1 ml/min
Class of compounds: Amines
Nature of compounds: Basic, Hydrophilic, Polar
Compounds: Methylamine, Dimethylamine, Trimethylamine