TY - JOUR

T1 - Two- and three-parameter equations for representation of retention data in reversed-phase liquid chromatography

AU - Pappa-Louisi, A.

AU - Nikitas, P.

AU - Balkatzopoulou, P.

AU - Malliakas, Christos D

PY - 2004/4/9

Y1 - 2004/4/9

N2 - Two-parameter equations that describe the dependence of lnk upon φ, where k is the retention factor and φ the volume fraction of the organic modifier in the mobile phase, are examined in what concerns the underlying approximations and their performance to fit experimental data obtained from reversed-phase liquid chromatography. Using 293 experimental systems, it was found that the performance of these equations to describe lnk versus φ data is rather low, since the percentage of the systems that can be described satisfactorily ranges from 40 to 60% depending on the fitting equation. This percentage may be raised to 75%, if the discreteness effect is properly taken into account. A further improvement to 90% of the systems studied can be achieved only by the use of three-parameter equations, which may arise by refinements of the rough approximations of the two-parameter equations. Although the refinements do not lead always to better equations, we developed a new three-parameter expression of lnk that works more satisfactorily, since it combines simplicity, linearity of its adjustable parameters and the highest applicability.

AB - Two-parameter equations that describe the dependence of lnk upon φ, where k is the retention factor and φ the volume fraction of the organic modifier in the mobile phase, are examined in what concerns the underlying approximations and their performance to fit experimental data obtained from reversed-phase liquid chromatography. Using 293 experimental systems, it was found that the performance of these equations to describe lnk versus φ data is rather low, since the percentage of the systems that can be described satisfactorily ranges from 40 to 60% depending on the fitting equation. This percentage may be raised to 75%, if the discreteness effect is properly taken into account. A further improvement to 90% of the systems studied can be achieved only by the use of three-parameter equations, which may arise by refinements of the rough approximations of the two-parameter equations. Although the refinements do not lead always to better equations, we developed a new three-parameter expression of lnk that works more satisfactorily, since it combines simplicity, linearity of its adjustable parameters and the highest applicability.

KW - Liquid chromatography

KW - Mathematical modelling

KW - Retention models

UR - http://www.scopus.com/inward/record.url?scp=1542328841&partnerID=8YFLogxK

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U2 - 10.1016/j.chroma.2004.01.021

DO - 10.1016/j.chroma.2004.01.021

M3 - Article

C2 - 15072288

AN - SCOPUS:1542328841

VL - 1033

SP - 29

EP - 41

JO - Journal of Chromatography A

JF - Journal of Chromatography A

SN - 0021-9673

IS - 1

ER -