Supplementary Appendix 2 to A Practical Approach to Modelling of Reversed-Phase Liquid Chromatographic Separations: Advantages, Principles, and Possible Pitfalls
LCGC Europe
This information is supplementary to the article “A Practical Approach to Modelling of Reversed-Phase Liquid Chromatographic Separations: Advantages, Principles, and Possible Pitfalls” that was published in the March 2018 LCGC Europe issue.
Flow diagram for modelling based on the manual approach
Optional determination of Vm Vd, ECBB and confirm linearity of gradient profile
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Select appropriate samples (that is, forced degradation, mother liquors etc.)
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Select suitable retention model (for example, log(k )= q1 + q2 F + q3 F2.)
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Select appropriate input experiments (tG, T etc.)
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Write methods and sequence (allowing sufficient time to equilibrate the new conditions)
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Collect input data for fitting and evaluation of models (typically performed overnight)
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Perform peak assignment / tracking (using MS, UV DAD, or peak areas), determine peak area, width, and asymmetry
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Produce Excel tables for each input experiment, copy, and paste into retention software input section
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Enter chromatographic conditions used
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Combine each individual input run into one large combined table
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Transfer input data to modelling software and fit models
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Evaluate resolution as a function of the operating variable examined (that is, gradient shape and T)
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Establish operational parameters fit for purpose (that is, identify robust conditions)
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Collection of data for confirmation of optimal conditions
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Optional in silico evaluation of other column formats, particle size, and flow
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