EVALUATION OF MOBILE-PHASE ADDITIVES IN LC-SYSTEMS USING CHEMOMETRICS

A strategy for general optimization of the mobile phase in LC-systems is described in this study. The influence on column efficiencies and c apacity factors of three uncharged modifiers, two charged modifiers, p H and column temperature was evaluated with experimental design and mu ltivariate analyses. A factorial design was used and the experimental results demonstrated that the uncharged modifiers and the pH were impo rtant for the capacity factors while column temperature and pH were im portant for the column efficiency. Two different stationary phase mate rials were used and compared, one was a traditional silica based mater ial and the other a silica covered with a polymer. Both were reversed phase materials. A partial least squares model obtained from the resul ts from the polymer column, Chromspher B, was used to predict retentio n data.