Article (Author postprint) (1.3 MB) - Limited access to UNIGE
Other version: http://www.sciencedirect.com/science?_ob=MImg&_imagekey=B6TG8-4VNK69B-2-H&_cdi=5248&_user=779890&_orig=search&_coverD...
Some solutions to obtain very efficient separations in isocratic and gradient modes using small particles size and ultra-high pressure
|Published in||Journal of Chromatography. A. 2009, vol. 1216, p. 32332-3243|
|Abstract||The UHPLC strategy which combines sub-2 μm porous particles and ultra-high pressure (>1000 bar) was investigated considering very high resolution criteria in both isocratic and gradient modes, with mobile phase temperatures between 30 and 90 °C. In isocratic mode, experimental conditions to reach the maximal efficiency were determined using the kinetic plot representation for ΔPmax = 1000 bar. It has been first confirmed that the molecular weight of the compounds (MW) was a critical parameter which should be considered in the construction of such curves. With a MW around 1000 g mol−1, efficiencies as high as 300,000 plates could be theoretically attained using UHPLC at 30 °C. By limiting the column length to 450 mm, the maximal plate count was around 100,000. In gradient mode, the longest column does not provide the maximal peak capacity for a given analysis time in UHPLC. This was attributed to the fact that peak capacity is not only related to the plate number but also to column dead time. Therefore, a compromise should be found and a 150 mm column should be preferentially selected for gradient lengths up to 60 min at 30 °C, while the columns coupled in series (3× 150 mm) were attractive only for tgrad > 250 min. Compared to 30 °C, peak capacities were increased by about 20–30% for a constant gradient length at 90 °C and gradient time decreased by 2-fold for an identical peak capacity.|
|Keywords||UPLC — UHPLC — HTLC — Temperature — Gradient — Peak capacity — Very high resolution|
|GUILLARME, Davy et al. Some solutions to obtain very efficient separations in isocratic and gradient modes using small particles size and ultra-high pressure. In: Journal of Chromatography. A, 2009, vol. 1216, p. 32332-3243. https://archive-ouverte.unige.ch/unige:1710|