A method to reduce gradient delay time of NanoLC.
A novel method to dramatically reduce the delay time of a nanoLC gradient is described. The gradient is divided into two parts, and each part is formed at different flow rates. The beginning part is formed and delivered to the inlet of the column at a higher-than-normal flow rate. With the formation of the rest of the gradient at a normal flow rate, the whole gradient is further delivered through the column at the same normal flow rate. To form the gradient with the desired slope, the volumetric gradient slope was kept constant, independent of the flow rate. A gradient delay time reduction of 12.5-16 min was observed with the reported method. The resulting gradient profiles and chromatograms were very similar to those obtained with a conventional method. Comparable retention time reproducibility was observed between the two methods.
Liu
Hongji
H
Life Sciences R&D, Waters Corporation, 34 Maple Street, Milford, Massachusetts 01757, USA. hongji_liu@waters.com
Finch
Jeffrey W
JW
Gebler
John C
JC
D002853:Chromatography, Liquid / Q000379:methods; D036103:Nanotechnology / Q000379:methods*; D011312:Pressure; D012680:Sensitivity and Specificity; D013997:Time Factors