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Separation of Isomers of Aminobutyric Acids |
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Application Notes:
Primesep C separates the isomers of aminobutyric acids by a combination of reversed-phase and ionic interaction mechanisms. alpha-Aminobutyric acid, beta-Aminobutryic acid, and gamma-Aminobutyric acid (GABA) are baseline resolved without ion-pair reagents. The HPLC separation uses a mobile phase of water, acetonitrile (MeCN, ACN) ammonium acetate with evaporative light scattering detection (ELSD).
Application Columns:
- Primesep® C is a mixed-mode HPLC column with reversed-phase, ion-exchange and host-guest complex formation properties. The Primesep C stationary phase combines a hydrophobic chain and an acidic functional group as a cation exchanger. Acids, bases, and neutrals can be retained and separated by Primesep 100 columns. Primesep C retains hydrophobic compounds by a reversed phase. Strongly polar and basic compounds such as quaternary amines are retained without the use of ion-pairing reagent by reversed phase and ion exchange. An unusual elution order compared to other HPLC columns is found for primary, secondary, and tertiary amines. Methods can be developed on Primesep columns that are fully compatible with detectors such as UV, RI, conductivity, fluorescence, evaporative light scattering (ELSD) as well as mass spectrometers (LC/MS) and preparative chromatography (prep HPLC) systems.
Application Analytes:
Application Detection:
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HPLC Separation of alpha-Aminobutyric, beta-Aminobutyric, and gamma-Aminobutyric acids on Obelisc N |
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Application Notes:
Application Columns:
- Obelisc N columns are the first commercially available columns with Liquid Separation Cell technology (LiSC). With multiple patents pending, LiSC technology is based on a new chemical modification of silica gel pores that creates a liquid separation cell with its own charge characteristics, ionic strength, and hydrophobic properties. Like living cells which exist in equilibrium with the outside environment, liquid separation cells exist in constant equilibrium with the mobile phase. Obelisc N, for normal phase, has very polar characteristics and works well for polar and charged analytes. In ion-exchange mode, charged analytes interact with oppositely charged groups on the stationary phase. In traditional HILIC mode, a charged or neutral polar analyte interacts with a water layer on the polar stationary phase surface. On Obelisc N the charges are greatly separated and independently accessible which results in different selectivity compared to traditional HILIC and silica columns. Mobile phase composition changes the conformation of the long hydrophilic chain. This affects the properties of the liquid separation cell and changes separation selectivity. Typical mobile phases used with Obelisc N columns are based on acetonitrile, water, and the mass spec compatible buffers ammonium formate (pH 3) and ammonium acetate (pH 5). If it is necessary to detect in low UV (<220 nm) then phosphate buffer is recommended. Obelisc N columns are compatible with mass spectrometers (LC/MS), evaporative light scattering detectors and preparative chromatography (prep HPLC) system.
Application Analytes:
Application Detection:
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