Fast separations at 1000 bar UHPLC

It is not trivial to build pumps for use at 1000 bar which fulfill the common requirements such as pulse-free flow which is independent of the pressure drop. Nevertheless it is possible the demand for high peak capacity (e.g. needed in proteomics) or for fast method development in industry led to the appearance of such instruments on the market. The technique is called ultra high pressure hquid chromatography (UHPLC). 

The theoretical background for separations up to 3000 bar was discussed comprehensively by Martin and Guiochon.It seems that various phenomena such as the compressibility of the mobile phase or thermal effects occur at pressures above 1000 bar, making it difficult to develop and optimize separations in this region. 

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