Abstract: A simplified one-dimensional thin-layer chromatography (TLC) method has been established for the identification of Paulownia species leaves,including Paulownia fortunei,Paulownia elongata,Paulownia tomentosa and Paulownia kawakamii.A single-factor experiment was conducted to select the optimal two-dimensional multiple development TLC method,which was then combined with column chromatography to segment the extract.Then,the one-dimensional TLC method was employed to identify the leaves of the four Paulownia species after developing the concentrated segments.The results showed that in the two-dimensional multiple expansion,characteristic spots of Paulownia fortunei were identified.Additionally,in the one-dimensional thin layer after segmented concentration,four common characteristic spots were observed for the four Paulownia species at 254 nm,seven common spots at 365 nm,and twelve common spots after color reaction under sunlight.The differences between Paulownia fortunei and the other three species were noted:on the developed TLC plate after color reaction,the first segment of the small polar sample showed a slightly yellow spot at an Rf value of 0.5,while the third segment of the large polar sample exhibited two light pink spots at an R_f value of approximately 0~0.2.

Key words: two-dimensional thin-layer chromatography, chromatographic identification method, Paulownia fortunei, quality control