Cathode-Ray Presentation of Chromatograms

Abstract

FROM the results of investigations on nylon capillary columns¹, it became apparent that there were two possible applications for the capillary system. The columns could be used to produce very high efficiencies with elution times of 10–60 min., or the high efficiencies could be sacrificed and chromatograms developed in a matter of seconds, with moderate efficiencies of perhaps 5,000 or 10,000 plates. Under these conditions it was found that a chromatogram of a mixture boiling over a range of about 100 deg. C. would be developed in 60 sec., the early peaks being eluted during a period of about 0.5 sec., but it was necessary to use a high-speed recording system with time constants of the order of milliseconds. Such a performance cannot be achieved by the normal potentiometric recorder, and the oscilloscope is an obvious alternative method of presenting the chromatogram.