Prediction of the chromatographic behaviour for a series of diuretic compounds

Abstract

SummaryThe proportion of organic modifier and the pH of the acetonitrile-water mixtures used as mobile phases were optimized in order to separate a group of diuretic compounds covering a wide range of physyco-chemical properties. The Linear Solvation Energy Relationship (LSER) formalism based either on the multiparameter re*,/3 and ce scales or the single solvent polarity parameter E7 N, have been used to predict their chromatographic behaviour as a function of the percentage of acetonitrile in the eluent. Moreover, correlation established between retention and pH of the aqueous-organic mobile phases have been used to predict the chromatographic behaviour of the diuretic compounds studied as a function of the eluent pH. Linear correlation between the chromatographic retention and the E~ polarity parameter of mobile phases containing different percentages of organic modifier has been obtained. Based on the knowledge of the acid-base dissociation constant the relation between retention and mobile phase pH has also been linearized. These relationships allowed an important reduction of the experimental retention data needed for developing a given separation and a great improvement in chromatographic optimization schemes.

Liquid chromatography?mass spectrometry approach for the characterization and purification of crude synthetic peptide hormones

“…2. This linearity has also been demonstrated in previous works for structurally different substances, obtaining different slopes which corre- ¬ spond to different structural regions of acetonitrile-water mixtures [21,22,23,24,25,26]. As all the data were obtained in one of the structural regions, the linear relationships obtained allow suitable prediction of the elution behaviour of peptide derivatives and hence optimisation of eluent composition from only two experimental measurements of k values for each analyte.…”

“…For the optimisation of the mobile phase composition, the linear solvation energy relationships (LSER) method, based on the single-solvent parameter was used as in previous works [21,22,23,24,25,26]. The linear relationship: (1) was applied to predict the retention of analytes at different acetonitrile percentages, between 25 and 35% (v/v), containing 0.1% (v/v) TFA.…”

“…Hence, the prediction of the elution profile of analytes on the basis of accurate quantitative relationships can be the basis for subsequent optimisation of the chromatographic conditions [15]. In previous studies the linear solvation energy relationship (LSER) methodology, based on the Kamlet-Taft multiparameter scale and on the scale of polarity [16,17,18,19,20], was used to predict the retention of series of peptides [21], quinolones [22,23], diuretics [24], anabolic steroids [25] and polyphenolic acids [26] in LC. This approach can be used to develop LC methodology to separate target peptides from other similar impurity peptide components, on the analytical scale and also on the preparative scale without lack of resolution.…”

Characterization of metallothionein isoforms from rabbit liver by liquid chromatography coupled to electrospray mass spectrometry

“…One approach for the development of analytical procedures is the application of experimental methods that can predict the chromatographic behavior of substances as a function of the percentage of the organic component in the eluent. To optimize the composition of the mobile phase, the linear solvation energy relationship (LSER) method, which is based on the Kamlet-Taft multiparameter scale, was used in the same way as in previous works [25][26][27][28][29][30]. The LSER approach applied to chromatographic processes [31][32][33] correlates retention parameters of solutes with characteristic properties of solutes and both stationary and mobile phases.…”

Optimization of HPLC conditions for the separation of complex crude mixtures produced in the synthesis of therapeutic peptide hormones

“…Undoubtedly, the stationary phase plays a major role in the separation process, but most researchers have focused attention on mobile phase optimization, since this is the easiest way to control retention and selectivity in LC. In previous studies the LSER method [18 21], based on the Kamlet-Taft multiparameter solvent scales, has been used to predict the chromatographic retention of series of peptides [22], quinolones [23], diuretics [24] and anabolic steroids [25] in LC, taking into account dependence of retention with chromatographic characteristics of solute, mobile phase and stationary phase:…”