Concurrent solvent evaporation is suited for coupled HPLC-HRGC if solutes elute at intermediate to high column temperatures-otherwise retention gap techniques are more appropriate. Concurrent eluent evaporation using a loop-type interface requires that the GC oven temperature during eluent introduct
Concurrent solvent evaporation for on-line coupled HPLC-HRGC
β Scribed by Grob, K. ;Walder, Ch. ;Schilling, B.
- Publisher
- John Wiley and Sons
- Year
- 1986
- Tongue
- English
- Weight
- 569 KB
- Volume
- 9
- Category
- Article
- ISSN
- 0935-6304
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β¦ Synopsis
A technique is proposed which allows introduction of very large volumes of liquid (10 ml were tested) into capillary columns equipped with short (1 -2 m long) retention gaps. It is based on concurrent solvent evaporation, i.e. evaporation of the solvent during introduction of the sample. The technique presupposes high carrier gas flow rates (at least during sample introduction) and column temperatures near the solvent boiling point. The major limitation of the method is the occurrence of peak broadening for solutes eluted up to 30Β°, in some cases up to looo, above the injection temperature. This is due to the absence of solvent trapping and a reduced efficiency of phase soaking. Therefore, use of volatile solvents is often advantageous. Application of the concurrent solvent evaporation technique allows introduction of liquids which do not wet the retention gap surface. However, the method is still not very attractive for analysis of aqueous or water-containing solutions (reversed phase HPLC).
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Concurrent solvent evaporation using the loop-type HPLC-GC interface requires that the GC oven temperature be above the eluent boiling point at the given carrier gas inlet pressure in order to prevent eluent flowing into the GC capillary column. Corresponding oven temperatures representing minimum o
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