Gradient elution demystified Of the various ways in which chromatography is applied today, few have been as misunderstood as the technique of gradient elution, which presents many challenges compared to isocratic separation. When properly explained, however, gradient elution can be less difficult to understand and much easier to use than often assumed. Written by two well-known authorities in liquid chromatography, High-Performance Gradient Elution: The Practical Application of the Linear-Solvent-Strength Model takes the mystery out of the practice of gradient elution and helps remove barriers to the practical application of this important separation technique. The book presents a systematic approach to the current understanding of gradient elution, describing theory, methodology, and applications across many of the fields that use liquid chromatography as a primary analytical tool. This up-to-date, practical, and comprehensive treatment of gradient elution: * Provides specific, step-by-step recommendations for developing a gradient separation for any sample * Describes the best approach for troubleshooting problems with gradient methods * Guides the reader on the equipment used for gradient elution * Lists which conditions should be varied first during method development, and explains how to interpret scouting gradients * Explains how to avoid problems in transferring gradient methods With a focus on the use of linear solvent strength (LSS) theory for predicting gradient LC behavior and separations by reversed-phase HPLC, High-Performance Gradient Elution gives every chromatographer access to this useful tool.

Gradient elution demystifiedOf the various ways in which chromatography is applied today, fewhave been as misunderstood as the technique of gradient elutionwhich presents many challenges compared to isocratic separation.When properly explained, however, gradient elution can be lessdifficult to understand and much easier to use than oftenassumed.Written by two well-known authorities in liquid chromatographyHigh-Performance Gradient Elution: The Practical Application of theLinear-Solvent-Strength Model takes the mystery out of the practiceof gradient elution and helps remove barriers to the practicalapplication of this important separation technique. The bookpresents a systematic approach to the current understanding ofgradient elution, describing theory, methodology, and applicationsacross many of the fields that use liquid chromatography as aprimary analytical tool.This up-to-date, practical, and comprehensive treatment of gradientelution:* Provides specific, step-by-step recommendations for developing agradient separation for any sample* Describes the best approach for troubleshooting problems withgradient methods* Guides the reader on the equipment used for gradientelution* Lists which conditions should be varied first during methoddevelopment, and explains how to interpret scouting gradients* Explains how to avoid problems in transferring gradientmethodsWith a focus on the use of linear solvent strength (LSS) theory forpredicting gradient LC behavior and separations by reversed-phaseHPLC, High-Performance Gradient Elution gives every chromatographeraccess to this useful tool.

PREFACE.GLOSSARY OF SYMBOLS AND TERMS.1 INTRODUCTION.1.1 The "General Elution Problem" and the Need forGradient Elution.1.2 Other Reasons for the Use of Gradient Elution.1.3 Gradient Shape.1.4 Similarity of Isocratic and Gradient Elution.1.5 Computer Simulation.1.6 Sample Classification.2 GRADIENT ELUTION FUNDAMENTALS.2.1 Isocratic Separation.2.2 Gradient Separation.2.3 Effect of Gradient Conditions on Separation.2.4 Related Topics.3 METHOD DEVELOPMENT.3.1 A Systematic Approach to Method Development.3.2 Initial Experiments.3.3 Developing a Gradient Separation: Resolution versusConditions.3.4 Computer Simulation.3.5 Method Reproducibility and Related Topics.3.6 Additional Means for an Increase in SeparationSelectivity.3.7 Orthogonal Separations.4 GRADIENT EQUIPMENT.4.1 Gradient System Design.4.2 General Considerations in System Selection.4.3 Measuring Gradient System Performance.4.4 Dwell Volume Considerations.5 SEPARATION ARTIFACTS AND TROUBLESHOOTING.5.1 Avoiding Problems.5.2 Method Transfer.5.3 Column Equilibration.5.4 Separation Artifacts.5.5 Troubleshooting.6 SEPARATION OF LARGE MOLECULES.6.1 General Considerations.6.2 Biomolecules.6.3 Synthetic Polymers.7 PREPARATIVE SEPARATIONS.7.1 Introduction.7.2 Isocratic Separation.7.3 Gradient Separation.7.4 Severely Overloaded Separation.8 OTHER APPLICATIONS OF GRADIENT ELUTION.8.1 Gradient Elution for LC-MS.8.2 Ion-Exchange Chromatography.8.3 Normal-Phase Chromatography.8.4 Ternary- or Quaternary-Solvent Gradients.9 THEORY AND DERIVATIONS.9.1 The Linear Solvent Strength Model.9.2 Second-Order Effects.9.3. Accuracy of Gradient Elution Predictions.9.4 Values of S.9.5 Values of N in Gradient Elution.Appendix I: THE CONSTANT-S APPROXIMATION IN GRADIENTELUTION.Appendix II: ESTIMATION OF CONDITIONS FOR ISOCRATIC ELUTION,BASED ON AN INITIAL GRADIENT RUN.Appendix III: CHARACTERIZATION OF REVERSED-PHASE COLUMNS FORSELECTIVITY AND PEAK TAILING.Appendix IV: SOLVENT PROPERTIES RELEVANT TO THE USE OF GRADIENTELUTION.Appendix V: THEORY OF PREPARATIVE SEPARATION.Appendix VI FURTHER INFORMATION ON VIRUS CHROMATOGRAPHY.Index.