Figure 7-3. Percentage of sample constituents that are resolvable as chromatographically distinct peaks (“singlets,” with a minimum resolution of 1.0) as a function of the number of compounds in a sample and different separation peak capacities. Effective peak capacities of 100 and 200 (dark gray in print versions) are easily achievable within 15 min using modern particle and instrument technologies. A peak capacity of 400 (light gray in print versions) is more difficult to reach for small molecules, but can be reached within an hour for peptides. An effective peak capacity of 3000 (gray in print versions) is not accessible by one-dimensional liquid chromatography in a practically reasonable time, but can be achieved by two dimensional liquid chromatography in 1-2 h. Singlet peak numbers were calculated assuming the same concentrations for all components and using Eq. (7.3) from Davis and Giddings.

*Click on image for full-size .jpg*

<< Back to Chapter 7 <<