PatJiways uf Decomposition of Indole Derivatives 



189 



Substances Separated by Electrophoresis 



Electropositive or basic substances and electronegative or acidic 

 substances were detected in ionograms at pH 7 (Figure 4). Substances 

 which remained at the starting line were mostly insoluble in the 

 phosphate buffer at that pH. Some, however, may have been 

 neutral or amphoteric. In chromatograms with multiple levels of 

 pH (Figure 2) acidic, basic, and amphoteric substances exhibited a 

 wavy pattern due to the different R( values of the forms of dissoci- 



-e- 



Fig. 5. Double chromatogram of indole-3-acetaldehyde. Ascending chromatogra- 

 phy, with water, in an atmosphere saturated with vapors of acetic acid. A-B, 

 distribution of spots after the first run; A, lAAL-sodium bisulfite addition com- 

 pound, B, ether extract of a solution of the same compound. After the first run 

 A was detached and sprayed with Ehrlich's reagent which revealed a purplish spot 

 of lAAL or of the addition compound. In B lAAL was seen under short-wave ul- 

 traviolet light as a dark elongated area. Three dots indicate the center of the 

 spots of the presumed polymers. It is suggested that the ultraviolet absorbing spot 

 that remained at the origin is also a polymer. Interrupted lines indicate a faint 

 yellow fluorescent tail above and below the large spot of lAAL. C, same chromato- 

 gram after the second run, sprayed with Ehrlich's reagent. lAAL now constitutes 

 the large square spot near the center of the chromatogram. Left behind is another 

 spot at the starting line, corresponding to the large spot of the first run in B but 

 probably of the same polymer as at the origin. All three spots exhibited the 

 same light blue color of lAAL in the Ehrlich reaction. In the square, large dots 

 on the diagonal indicate the center of primary spots of the three presumed poly- 

 mers; small dots indicate the secondary spots of the same polymers formed by 

 polymerization and depolymerization during chromatography. 



