Effect of temperature on the chromatographic retention of ionizable compounds

Gagliardi, Leonardo Gabriel; Castells, Cecilia Beatriz Marta; Ràfols, Clara; Rosés, Martı́; Bosch, Elisabeth

doi:10.1016/j.chroma.2005.04.070

Cited by 33 publications

(24 citation statements)

References 53 publications

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“…As discussed above, at higher pH (pH 4.2 or 5.2), because ion-exchange interaction was greater, the pK a of the bases becomes an important parameter governing retention. As proposed in previous literature [8,9,24], the pK a of solutes decreases with increasing temperature, and the smaller the pKa of the base is, the more it decreases. Since the pK a value of epirubicin (pK a 8.08) is smaller than that of daunorubicin (pK a 8.46), a greater reduction of the protonated species will be obtained for epirubicin.…”

Section: Temperature Effect At Various Buffer Phsmentioning

confidence: 53%

“…As discussed above, ion-exchange interaction is responsible for retention of solutes at higher pHs. However, it is a slow mass transfer step [9], thus leading to lower efficiency. With increasing temperature, improved efficiencies are observed at all the pHs tested.…”

Section: Temperature Effect At Various Buffer Phsmentioning

confidence: 99%

“…Therefore, over the past few years, the use of temperature as a variable controlling selectivity and separation speed has become more popular [1,2]. However, most of the studies on temperature effects have focused on the two classical chromatographic modes-reversed-phase liquid chromatography (RPLC) and normal phase liquid chromatography (NPLC) [3][4][5][6][7][8][9][10][11]. Work on the role of temperature on bare silica using reversed-phase solvents is beginning to appear.…”

Section: Introductionmentioning

confidence: 99%

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Effect of temperature on the chromatographic behavior of epirubicin and its analogues on high purity silica using reversed-phase solvents

DONG¹,

HUANGL²

2007

Chromatographia

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The influence of temperature on the retention behavior of epirubicin and its analogues on high purity silica with reversed-phase solvents has been systematically investigated. It was found that temperature effects on retention are highly dependent on the type and concentration of organic modifier, as well as the pH of the mobile phase. In organic-rich mobile phases, the type of organic modifier plays an important role. With an aprotic solvent as modifier, retention times show anomalous increases with elevated temperature. At the same time, both efficiency and resolution are significantly improved but this is not the situation with a protic solvent as modifier. In addition, temperature shows different effects on retention time and selectivity when the pH is changed, and temperature-dependent selectivity reversal is found at higher pHs. In aqueousrich mobile phases, regardless of the nature of the organic solvent and pH, retention of solutes drops as temperature is raised. It seems that the effect of temperature on chromatographic behavior of the solutes on bare silica using mobile phases containing various organic modifiers or pHs, results from a number of different retention mechanisms.

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Section: Temperature Effect At Various Buffer Phsmentioning

confidence: 53%

Section: Temperature Effect At Various Buffer Phsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

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Effect of temperature on the chromatographic behavior of epirubicin and its analogues on high purity silica using reversed-phase solvents

DONG¹,

HUANGL²

2007

Chromatographia

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“…This is especially true for polar and ionizable compounds since ionization equilibria are temperature dependent. A systematic study of the effect of temperature (25-508C) on the retention of ionizable compounds in methanol-water mobile phases [104] and ACN-water mobile phases [105] showed significant changes in selectivity. This has been demonstrated repeatedly in the literature, yet its potential role in method development is often underestimated.…”

Section: Selectivitymentioning

confidence: 99%

Elevated temperature and temperature programming in conventional liquid chromatography – fundamentals and applications

Vanhoenacker

Sandra²

2006

J of Separation Science

101

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Temperature, as a powerful variable in conventional LC is discussed from a fundamental point of view and illustrated with applications from the author's laboratory. Emphasis is given to the influence of temperature on speed, selectivity, efficiency, detectability, and mobile phase composition (green chromatography). The problems accompanying the use of elevated temperature and temperature programming in LC are reviewed and solutions are described. The available stationary phases for high temperature operation are summarized and a brief overview of recent applications reported in the literature is given.

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“…The same is true for the buffer. The s s pK a for phosphate at pH 2.8 and 7.9 and acetate at pH 5.5 in 25% MeCN did not change at all in the range from 15 to 508C, while the values for piperazine, Tris, and butylamine decreased by about 1 pH unit [191]. For butylamine, the s s pK a value changed by about 1 unit from 20 to 508C in a methanol-based mobile phase [190].…”

Section: Methods Developmentmentioning

confidence: 93%

Stationary phase characterization and method development

Neue

2007

J of Separation Science

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The properties of stationary phases and their characterization methods are reviewed. New and significant developments have occurred in the last few years, and new methods for stationary phase characterization have become available. The characterization methods are discussed, and the differences between the different methods are pointed out. In addition, method development approaches are reviewed, with special emphasis on recent developments that employ multiple parameters in parallel. Also, the renewed interest of temperature as a tool in method development is surveyed.

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Effect of temperature on the chromatographic retention of ionizable compounds

Cited by 33 publications

References 53 publications

Effect of temperature on the chromatographic behavior of epirubicin and its analogues on high purity silica using reversed-phase solvents

Effect of temperature on the chromatographic behavior of epirubicin and its analogues on high purity silica using reversed-phase solvents

Elevated temperature and temperature programming in conventional liquid chromatography – fundamentals and applications

Stationary phase characterization and method development

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