Ultra high performance liquid chromatography UHPLC

There are a variety of HPLC columns and most of them are based on silica particles. The most popular column used today is the reversed-phase Cl8 column that uses a silica support with a bonded organic surface layer. Traditional HPLC analytical columns are usually 4.6 mm x 250 mm with a 5 pm particle size, as used in the USP official method. Modern columns for HPLC-mass spectrometry (LC-MS) applications are more efficient and offer the same or better resolving power in a much smaller package (2.1 mm x 150 mm with a 3.5 pm particle size or smaller). Ultra high-performance liquid chromatography (UHPLC) columns (sub 2pm particle size, 1-2 mm in diameter and 30-100 mm in length) are becoming more and more popular. 

UFIPLC. See Ultra high performance liquid chromatography (UHPLC)... 

Ultra high performance liquid chromatography (UHPLC) or ultra performance liquid chromatography (UPLC) is a quite novel technique, but it is one of the most popular nowadays, due to the fact that it is much more rapid than conventional LC. UHPLC systems can work at very high pressures and are compatible with stationary phases with particle sizes of around two micrometers or even smaller. Thus, the development of UHPLC methods [69,77, 80] or the conversion of HPLC to UHPLC methods is a current trend, due mainly to the speed of analysis and low solvent use. 

Kovalczuk et al. [81] developed a high-throughput method for multiresidue pesticide analysis in food matrices based on ultra high-performance liquid chromatography (UHPLC) with coupling to tandem mass spectrometry. Separation of 17 polar pesticides was achieved in under 8 min (see Figure 13.5). The authors compared UHPLC and conventional LC approaches, and they observed higher separation efficiencies with the LC method. Faster separations and better limits of quantitation were possible with the UHPLC method, however. A different approach for multiresidue... 

Particle size Plate height and column permeability decrease with the particle diameter. Smaller particle size columns provide, therefore, a better resolution. This concept, which led to the development of Ultra High Performance Liquid Chromatography (UHPLC), can also be adapted to SEC taking some peculiarities into account. Figure 9.10 shows a comparison of a protein mixture... 

---