Quaternary gradient solvent systems

The system shown is capable of performing a quaternary gradient and shows all of the elements to be considered for industrial scale separations. For instance, a solvent reservoir size of 1-2 m3 would allow continuous operation for several hours. Separations carried out at this scale will be extremely well-defined with respect to fraction size and point of collection so very few fraction collection vessels would be required. 

Table F4.4.1 Linear Gradient Conditions for Separation of Chlorophylls and Their Nonpolar Derivatives Using a Ternary/Quaternary Solvent Delivery System...

Another means of controlling eluent strength is the use of ternary or quaternary solvent mixtures instead of the more common binary approach. Each solvent has its own unique properties that can be used to improve the separation of difficult-to-resolve analytes or to shorten the analysis time without sacrificing resolution. Although gradients and more complex solvent matrices are more difficult to model than binary isocratic systems, software exists for such purposes and can assist in method development. 

The HPLC analyses were conducted with a Water 600 Pump apparatus. This apparatus was equipped with a quaternary solvent delivery system, a Rheodyne injector with 20qL sample loop and a UV detector Waters 486 Tunable which was fixed at 280 nm. Throughout this study. Alltech Intertsil ODS-5 C18 reversed phase column (150 mm, 4.6 mm, 5qm particle size) was used. The flow rate of the mobile phase was of 1 mL / min and the gradient elution was adapted from (Nakatani et al., 2000 Bouayed et al, 2007). The solvent composition and the gradient elution program are reported in the table 1. 

For the standard configuration, an automatic column selection valve for accommodating two different columns is required, and solvent switching is performed using the channels of a quaternary low-pressure gradient pump. This configuration can be realized for all HPLC systems supported by ChromSword . 

---