Dragendorff spray reagent

Phospholipid and PEG alone or their conjugates are visualized by phosphomolybdic acid and Dragendorff spray reagents (see Note 1). 

FIGURE 11.6 (a) Densitogram of PLC of Fumaria officinalis herb extract and (b) photocopy of isolated fractions (after spraying with Dragendorff s reagent). Numbers indicate isolated fractions. System silica/CHjClj + PrOH + AcOH (5 4 1). Plates double developed. 

FIGURE 11.23 Densitograms of Fumaria muralis herb extract chromatographed in system silica/PrOH + MeOH + AcOH + water + CHjClj (28 2 2 2 66). Plates double developed (a) plate scanned at 254 nm (b) plate scanned at 400 nm after spraying with Dragendorff s reagent. 

Figure 11.23a and Figure 11.23b show densitograms from the separation of Fumaria muralis extract scaimed in UV 254 mn (Figure 11.23a) and at 400 nm after spraying with Dragendorff s reagent (Figure 11.23b). It is seen that derivatization enables determination of alkaloid zones and their isolation from the nonalkaloid extract components.

In the procedure with mobile phase 1 and 2, the visualization is accomplished by screening under uv light (254 and 366 nm) and in addition by spraying with Dragendorff s reagent, modified by Munier and Deboeuf, followed by 30 percent hydrogen peroxide. 

Beside the modified Dragendorff s reagent/hydrogen peroxide already mentioned, a variety of spraying reagents has been used for the visualization of bromocriptine. 

Violet yvithfurfuraldehyde reagent t Weak reaction with Dragendorff spray t Positive reaction with Dragendorff spray... 

Thin-layer Chromatography. System TA—Rf 50 system TB—Rf 30 system TC—Rf 35. Dragendorff spray, positive acidified iodoplatinatesolution, positive Marquis reagent, red-brown.)... 

Thin-layer Chromatography. System TA—Rf 71 system TB—Rf 09 system TC—Rf 30 system TL—Rf 64. Dragendorff spray, posiii q acidified iodoplatinate solution, pos i Q,ninhydrinspray, positive Van Urk reagent, bright yellow.)... 

Thin-layer Chromatography. System TA—Rf 75 system TD—Rf 63 system TE—Rf 78 system TF—Rf 62. Dragendorff spray, weak reaction acidified iodoplatinate solution, positive mercuric chloride-diphenylcarbazone reagent, positive mercurous nitrate spray, black.)... 

Thin-layer Chromatography. Sy.stem TA—Rf 52 system TB—Rf 07 system TC—Rf 62 system TD—Rf 43 system TE—Rf 61 system TF—Rf 47. (Dragendorff spray, positive FPN reagent, pale yellow Marquis reagent, very weak pale yellow mercuric chloride-diphenylcarbazone reagent, blue, on heating turns pale pink acidified potassium permanganate solution, positive.)... 

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