Chromatography mixed-mode liquid

Figure 3.177 Separation of hydrophilic monocarboxylic acids with mixed-mode liquid chromatography. Separator column Acclaim Mixed-Mode WAX-1, 5 pm column dimensions 150 mm X 4.6 mm i.d. column temperature SOT eluent 25 mmol phosphate buffer,...

Mixed-mode liquid chromatography on silica-based stationary phases incorporating both hydrophobic and weak anion-exchange properties... 

Besides low-molecular weight organic acids and bases, cleansing agents also contain surfectants, which are typically analyzed either by ion-pair chromatography on a nonfimctionalized DVB polymer or by mixed-mode liquid chromatography on... 

Figure 10.196 Separation of common cationic surfactants using mixed-mode liquid chromatography and charged aerosol detection. Separator column Acclaim Surfactant Plus, 3 pm column dimensions 150mmx3mm i.d. column temperature 30 °C eluent (A) MeCN and (B) 0.1 mol/L NH4OAC, pH 5 gradient 35% to 85% A (v/v) in 8 min flow rate 0.6mtymin detection Corona CAD (gain 100pA fiiten...

Figure 10.201 Gradient elution of anionic surfactants in a shampoo using mixed-mode liquid chromatography on a silica-based column. Separator column Acclaim Surfactant Plus,...

In case anionic and cationic counterions have to be separated in the same chromatographic run, mixed-mode liquid chromatography with nonspecific... 

Figure 10.307 Simultaneous separation of 1,1-dimethylbiguanide (metformin) and its chloride counterion by mixed-mode liquid chromatography. Separator column Acclaim Trinity PI, 3 pm column dimensions 50mm X3mm i.d. column temperature 30°C ...

The present edition is considerably updated and expanded, covering all aspects of ion chromatography and all developments in this field that have been introduced over the past 10 years. This includes the application of hydrophilic interaction and mixed-mode liquid chromatography for the determination of ionic and ionizable compounds, the introduction of novel detection methods and hyphenated techniques, the design of new separation media for capillary and monolithic columns, columns packed with particulate ion exchangers having smaller particle diameters, and mixed-mode stationary phases. 

A mixed-mode method called liquid chromatography under limited conditions of adsorption has been described and applied to analyzing co-polymer composition of poly(styrene)-co-(methylmethacrylate).41 The polymer, dissolved in a good solvent, was injected onto a GPC column and eluted with a poor solvent. The polymer partially adsorbed to the column, allowing the plug of injection solvent to catch up with the adsorbed polymer and desorb it. 

Ferguson PL, Iden CR, Brownawell BJ (2001) Analysis of nonylphenol and nonylphenol ethoxylates in environmental samples by mixed-mode high performance liquid chromatography-electrospray mass spectrometry. J Chromatogr A 938 79-91... 

This section deals briefly with classical methods based on conventional mixing of the sample and reagents such as the batch mode and low-pressure flow mixing methods, as well as the use of CL detection in continuous separation techniques such as liquid chromatography and capillary electrophoresis for comparison with the unconventional mixing mode. 

Nogueira, R., Lubda, D., Leitner, A., Bicker, W, Maier, N.M., Lammerhofer, M., and Lindner, W, Silica-based monohthic columns with mixed-mode reversed-phase/weak anion-exchange selectivity principle for high-performance liquid chromatography, J. Sep. ScL, 29, 966, 2006. 

Vergara, C. Mardones, C. Hermosin-Gutierrez, 1. von Baer, D. 2010. Comparison of high-performance liquid chromatography separation of red wine anthocyanins on a mixed-mode ion-exchange reversed-phase and on a reversed-phase column. J. Chromatogr. A. 1217 5710-5717. 

JT Eleveld, HA Claessens, JL Ammerdorfer, AM van Herk, CA Cramers. Evaluation of mixed-mode stationary phases in liquid chromatography for the separation of charged and unchaiged oligomer-like model compounds. J Chromatogr A 677 211-227, 1994. 

Strege, M.A. Sevenson, S. Lawrence, S.M. Mixed-Mode Anion-Cation Exchanged lydrophilic Interaction Liquid Chromatography-Electrospray Mass Spectrometry as an Alternative to Reversed Phase for Small Molecule Drug Discovery, Anal. Chem. 72,4629-4633 (2000). 

F. Mashige, Y. Matsushima, C. Miyata, R. Yamada, H. Kanazawa, I. Sakuma, N. Takai, N. Shinozuka, A. Ohkubo and K. Nakahara, Simultaneous determination of catecholamines, their basic metabolites and serotonin in urine by high-performance liquid chromatography using a mixed-mode column and an eight-channel electrochemical detector, Biomed. Chromatogr, 9, 221-225 (1995). 

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