EXPLORING HIDDEN TRENDS IN CLASSIC AND MICELLAR THIN-LAYER CHROMATOGRAPHIC RETENTION OF MODEL COMPOUNDS BY CHEMOMETRIC METHODS

Abstract

We present chemometric analysis of the retention of 35 simple model compounds in nonmicellar and micellar TLC systems. Nonmicellar systems were investigated on silica gel, RP18, and CN plates, by use of several modifiers in hexane or water as the mobile phase. Micellar systems were processed on silica and RP8 plates with three surfactants (cetyltrimethylammonium bromide, sodium dodecylsulfate, and Triton-X100) dissolved in water above critical micellar concentration. The resultant dataset was subjected to principal component analysis (PCA) to explore hidden trends in retention. It was concluded that PCA is a valuable tool for factor analysis of retention, as it allows the chromatographer to see and interpret all trends which would be hidden in manual analysis of retention matrix. Retention on each adsorbent can be decomposed to maximally four main independent trends and each compound has be characterized by intensity of these trends, expressed as PCA scores.

Keywords:

• chemometrics
• micellar TLC
• principal component analysis
• retention

ACKNOWLEDGMENT

We acknowledge the computational support of the Interdisciplinary Center of Mathematical Modeling, Warsaw University, Poland (Grant No. G3-8).