The goal of this work is to evaluate and identify cation-exchange columns suitable for applications involving quaternary amine compound (QAC) determinations. Four Thermo Scientific Dionex IonPac columns (CS17, CS19-4µm, CS20, and CS21-4µm) were evaluated. A Thermo Scientific™ Dionex™ ICS-5000+ HPIC™ system that produced an electrolytically generated methane sulfonic acid (MSA) eluent was used for this work. The results for retention time, peak area, peak asymmetry, and efficiency are included here along with recommendations for choosing a column for QAC determinations.
Succinylcholine chloride is an approved intravenous (IV) medication used as a skeletal muscle relaxant during procedures of short duration. Choline Chloride is an impurity. An improved ion chromatography (IC) method is proposed for the limit of choline test in the USP Succinylcholine Chloride monograph. A Thermo Scientific Dionex IC system with a Thermo Scientific Dionex IonPac CS19 anion-exchange column and suppressed conductivity detection were used for the method. This application note reports the method development and evaluation.
Choline is a water soluble essential nutrient that is produced in the body in small quantities. Choline is a precursor of acetylcholine which is an important neurotransmitter involved in muscle control and memory. Choline is a small, highly polar quaternary amine and will not be retained using a C18 column. The zwitterionic nature of Syncronis HILIC makes it ideal for the retention of this class of compound. This application note demonstrates the successful analysis of acetylcholine and choline using a Syncronis HILIC 1.7 µm column.
Choline and acetylcholine are quaternary ammonium cations which are noted for their activities as neurotransmitters. This is an older application note that shows these compounds can be determined by IC. Today we would probably use an IonPac CS19 column as shown in Application Update 189.
A simple RFIC method is described for determination of carbachol, bethanechol, and choline in 25 min with a Dionex IonPac CS17 column. Methanesulfonic acid (MSA) eluent is delivered isocratically by an Eluent Generator (EG). Use of an EG eliminates eluent preparation errors and helps ensure retention time reproducibility. The sensitivity of suppressed conductivity detection allows carbachol determination in ophthalmic solutions with only a simple sample dilution.
