High-performance liquid chromatography solvent pumps

A continuous process was performed by van Eijs et al. [69] and Marty et al. [54], Substrates can be continuously injected into the SCCO2 flow by a high-performance liquid chromatography (HPLC) pump. The substrate concentration is known, an adjustment to a fixed value is possible. In this case the CO2 was not recycled. They also developed a continuous process with recycling of CO2 and post reactional fractionation (Fig. 2) [2], Table 3 shows studies of important parameters for reactivity and productivity of enzymatic reactions in supercritical media. Furthermore, some authors compare supercritical media and conventional organic solvents ... 

Figure 7.5 Schematic diagram of a high performance liquid chromatography (HPLC) system. The solvent(s) are pumped through the system, and the sample injected just before the column where separation occurs. Detection is often by UV/visible spectrophotometry at a fixed wavelength.

High Performance Liquid Chromatography (HPLC) (Chapter 30) gives an elaborate discussion of theoretical aspects. Instrumentation encompasses the various important components e.g., solvent reservoir and degassing system pressure, flow and temperature pumps and sample injection system ... 

This consists of a solvent delivery for isocratic reversed phase and gel filtration chromatography. The isocratic system (Fig. 1.1) provides an economic first step into high performance liquid chromatography techniques. The system is built around a high performance, dual-piston, pulse-free pump providing precision flow from 0.01 to 5mL min-1. 

A typical high-performance liquid chromatography (HPLC) system consists of two pumps, a mixer, an injector, a guard colunm, a separation column, a detector, an electrospray nozzle, and a mass spectrometer. The two pumps and the mixer allow establishment of desired solvent gradients. The injector is used to inject a small amount of sample into the column. In all separation techniques, definition of a small volume of injected sample is cmcial in preventing adverse broadening of peaks and a consequent loss in compmient resolution. The injected compounds are separated in the separation colunm and then detected via a simple detector or a mass spectrometer. All of the parts of the HPLC system have been miniaturized, and several research groups have been able to demonstrate on-chip HPLC separations. 

Dongjin Pyo also reported some other procedures The extraction by SFE was performed with a Beckman 116 pump (System Gold programmable solvent module 126), a 15 cm X 10 mm l.D. ODS column and Agilent high-performance liquid chromatography (HPLC) 1100 series diode-array detector. Methanol/0.05 M phosphate buffer... 

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