A two-dimensional thin-layer chromatographic fingerprint has been developed on a polyamide plate for the quality control of Helleborus thibetanus Franch. The investigated sample was separated by chloroform-ethyl acetate-methanol (3.0:8.0:4.4, v/v) in the first dimension and isooctane-n-propyl alcohol-water (10:2.5:1.0, v/v) adding 0.28 mol L−1 sodium dodecyl sulfate, a reversed micelle, in the second dimension. The plate was dried in the air at room temperature and examined in ultraviolet (UV) light at λ = 365 nm after development. The two developments were carried out over a distance of 70 mm. The two-dimensional thin-layer chromatographic method was validated in terms of repeatability, stability, and robustness. For fingerprint analysis, nine spots were identified as common spots. Statistical method (canonical correlation analysis) was first used to calculate the degree of similarity between the two-dimensional chromatograms. The proposed method was novel and accurate for the identification and quality evaluation of H. thibetanus Franch.
P. Liu, L. Song, Y. Ren, X.H. Tian, X.H. Zhang, Acta Bot. Boreali- Occident. Sin. 26 (2006) 2208–2213.