Flavone reagent

Detection and result The developed chromatogram was heated to 80°C for 15 min the warm plate was sprayed first with Flavone Reagent (3% in methanol)... 

Flavone reagents quercetin [71,72] and morin (formulae 57.4 and 57.3) [73] have been recommended for determining tin. In the presence of antipyrine, the Sn(IV) compounds can be extracted into chloroform [73]. 

Derlvatlzatlon reagent hRf-values Dlphenylborlc acld-2-amlnoethyl ester reagent and polyethylenglycol 6000 (Flavone reagent acc. to Neu) Colours of fluorescence ... 

With some reagents, it is advisable to spray a heated plate to cause the solution to evaporate more quickly, as a further spraying process with a different reagent is often subsequently performed, e.g. with the flavone reagent according to Neu [101]. In these cases, the plate is placed in front of a hot-air dryer after the documentation and before the derivatization. The derivatization can then proceed more rapidly and the layer can take up more solvent without causing the substances to run. 

See Section 6.3.1, Fig. 84 various species of Echinacea derivatized by the flavone reagent according to Neu and stabilized with a 2 % ethanolic solution of Magrocol 400. 

UV305 nm after spraying with the flavone reagent acc. to Neu... 

Figure 5Z Difference between matured and fresh solvent system on the chromatographic result using the example of flavonoid-containing dry extracts (DE) (shots in 365-nm UV light after derivatization with the flavone reagent according to Neu)...

Figure 84. Identification of three species of coneflower (Echinacea) and detection of a hybrid of two of these after spraying with the flavone reagent according to Neu (shots in 365-nm UV light). All the plant material is from authentic cultivation in Middle Franconia (northern Bavaria), and the chromatography was performed 40 hours after harvesting (by the author) in June 1996 only above-ground parts of plants which were not in flower were investigated. AU the parameters of the TLC are listed in Table 19.

---