By Tony on Monday, March 24, 2003 - 03:11 am:
Has anyone had success obtaining a stable baseline with refractive index detection when working with isocratic mobile phases obtained by blending pure solvents rather than by pre-mixing
e.g. 20:80 ethyl acetate:hexane ?
Which type of mixing - low pressure using 1 pump and proportioning or high pressure using 2 pumps would be expected to give better results?
TIA
Tony
By Benjamin on Monday, March 24, 2003 - 10:24 am:
Tony;
This idea is something of a dream that has been attempted since the early days of LC, together with the dream of sdesigning a gradient system capable of RI work. RI detectors are so sensitive to RI changes that the best pumps/mixers and related controls etc, are not good enough to give you perfect baselines.
To my knowledge the ideas of pump-mixing for RI and the use of gradients, has been never achieved in practical terms, and probably never will be.
Benjamin