Multisegment programs

Selectivity optimization of simple, continuous gradients will be easier than the optimization of complex multisegment programs, because there are bound to be serious... 

Stan and Steinbach [613] have described a sequential optimization procedure for programmed temperature GC that searches for an optimum multisegment program in a systematic way. This procedure can be divided into three different stages ... 

Figure 6.2 Different shapes of elution programs in chromatography. Description of programs (a) step (b) linear (c) convex (d) concave (e) multisegment.

Simplex optimization of the primary (program) parameters in programmed temperature GC analysis has been demonstrated [612]. A systematic sequential search [613] may be used as an alternative. The Simplex method may be used to optimize a limited number of program parameters, whereas the latter approach was developed for the optimization of multisegment gradients. The use of interpretive methods has so far only been suggested [614,615]. 

The example shown in figure 6.10 (ref. [613]) for the optimization of a multisegment temperature program was more impressive. Unfortunately, the required number of experiments was large (21). The selection of simple criteria (e.g. maximum number of peaks) may greatly enhance the possibilities for fully automatic optimization. 

A systematic sequential optimization procedure may be used to establish an optimum multisegment temperature program. 

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