Criteria for optimizing the separation of target analytes in complex chromatograms

Chromatographic response functions in 1D and 2D chromatography as tools for assessing chemical complexity

“…It then becomes necessary to transform these individual criteria into a global separation criterion. Several global separation criteria have been already reviewed [1,12], and the most used are the separation of the worst separated peak pair, and the sum and the product of all individual criteria, and some others are more complex (e.g., the normalized resolution product, which has already been used in target analysis) [17,18]. Although several of these individual elementary criteria have been used separately for optimizing the chromatographic conditions, it is considered that a chromatogram should be classified taking into account not only one criterion, but a relationship between the various elementary criteria.…”

Development of flexible and efficient strategies for optimizing chromatographic separations

“…In this paper, the described optimization examples are based on experimental data already reported in previous articles [6,7]. The first set of data [6] concerned a mixture of four acidic solutes (benzoic acid, m-nitrobenzoic acid, 3,5-dinitrobenzoic acid and salicylic acid).…”

“…3, Table 2 lists the values of the minimum resolu- Table 2 Values of analysis time (t analysis ), minimum resolution (R S , min ), and of the minimum effective resolution (R l, min ) corresponding to the chromatograms presented in Fig. 3a- takes into account peak asymmetry and the difference in peak heights [7,10]:…”

“…So, the calibrated normalized resolution product, r6 * (Eq. (7)) promotes situations where relevant peaks are equally distributed over the chromatogram (same resolution) and where, ideally, all irrelevant peaks are confounded with a (hypothetical) t 0 peak [7]. When these two conditions are fulfilled, r6 * is equal to one.…”

“…In conclusion, improved optimization criteria which can deal with non-ideal peaks and with limited optimization now exist [7] and these should be integrated in all optimization software.…”