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HPLC Separation of Parabens and Benzoic Acid |
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Application Notes:
Application Columns:
- Primesep® B2 is a mixed-mode HPLC column with general hydrophobic and ion-exchange properties. The Primesep B2 stationary phase combines a hydrophobic chain and a basic functional group as an anion exchanger. Acids, bases, zwitterions and neutrals can be retained and separated by Primesep B2 columns. Primesep B2 also separates bases by an ion-exclusion mechanism. Primesep B2 demonstrates significant improvement in retention and selectivity for the separation of weak acid analytes by a combination of reversed phase and anion exchange. In this case the basic functional group acts as an embedded ion-pairing reagent. Primesep B2 column is one of the best separation media for natural product extracts. 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 Polar and Hydrophobic Drugs on Obelisc R and 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.
- Obelisc R 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 R, for reversed phase, has reversed-phase character and can be used in traditional, reversed-phase type applications. Due to the presence of ionic groups and a long hydrophobic chain, Obelisc R offers additional retention and tuning that is not available with traditional reversed-phase columns. Reversed-phase separations are augmented by additional ionic and polar interactions not available on traditional reversed-phase C18 columns. Mobile phase composition changes the conformation of the long hydrophobic chain and affects the properties of the liquid separation cell and changes separation selectivity. Typical mobile phases used with Obelisc R 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 R columns are compatible with mass spectrometers (LC/MS), evaporative light scattering detectors and preparative chromatography (prep HPLC) systems.
Application Analytes:
Application Detection:
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HPLC Separation of Methyl Paraben, Benzonitrile, Propyl Paraben, and Toluene on Mixed-Mode and Reverse Phase Columns |
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Application Notes:
Application Columns:
- Obelisc R 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 R, for reversed phase, has reversed-phase character and can be used in traditional, reversed-phase type applications. Due to the presence of ionic groups and a long hydrophobic chain, Obelisc R offers additional retention and tuning that is not available with traditional reversed-phase columns. Reversed-phase separations are augmented by additional ionic and polar interactions not available on traditional reversed-phase C18 columns. Mobile phase composition changes the conformation of the long hydrophobic chain and affects the properties of the liquid separation cell and changes separation selectivity. Typical mobile phases used with Obelisc R 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 R columns are compatible with mass spectrometers (LC/MS), evaporative light scattering detectors and preparative chromatography (prep HPLC) systems.
Application Analytes:
Application Detection:
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