| Abstract: | Size exclusion chromatography (SEC) is capable of evaluating the molecular weight distribution (MWD) of a sample. Information about the chemical composition distribution can be gained by gradient high performance liquid chromatography (gradient HPLC), where a poor starting eluent is, in the course of the separation, substituted by another one of increasing elution strength. Both normal-phase and reversed-phase systems can be employed. The combination of SEC and gradient HPLC enables chromatographic cross-fractionation to be performed efficiently. |
