Selectivity evaluation of core-shell sislica columns for reversed-phase liquid chromatography using the solvation...

Area of Science:

• Analytical Chemistry
• Chromatography

Background:

• Core-shell silica and siloxane-bonded reversed-phase columns are widely used in chromatography.
• Evaluating column selectivity is crucial for method development and optimization.
• The solvation parameter model provides a framework for understanding chromatographic retention behavior.

Purpose of the Study:

• To identify a minimal set of calibration compounds for evaluating the selectivity of core-shell silica, siloxane-bonded reversed-phase columns.
• To optimize calibration models using the solvation parameter model for various mobile phase compositions.
• To assess the predictive capability of the developed models.

Main Methods:

• Utilized the Kennard-Stone uniform mapping algorithm to select 35 calibration compounds from a larger database.
• Employed the solvation parameter model to build calibration models for column selectivity evaluation.
• Investigated mobile phases containing 20-70% (v/v) methanol- or acetonitrile-water.
• Constructed system maps and correlation diagrams using system constants determined at 10% (v/v) organic solvent increments.

Main Results:

• A minimal set of 35 calibration compounds demonstrated high predictive capability with a root mean square error of prediction (log k) of 0.028.
• Calibration models achieved high coefficients of determination (0.970-0.999) and low standard errors of estimate (<0.030 for 75% of models).
• System maps and correlation diagrams effectively illustrated column selectivity for various Kinetex columns and mobile phases.

Conclusions:

• A minimal set of 35 calibration compounds is sufficient for accurate selectivity evaluation of core-shell silica, siloxane-bonded reversed-phase columns.
• The solvation parameter model, combined with optimized calibration sets, provides a robust approach for predicting chromatographic behavior.
• The developed methodology aids in selecting appropriate columns and mobile phases for specific analytical applications.