Chloroform dip solutions

Figure 3. Chloroform dip solution contained 3.2% 4-chlorobenzophenorte plus zirconium...

Figure 5. Chloroform dip solutions contains amounts of compounds as indicated...

Figure 2. Chloroform dip solution contained plus 4-chhrobenzophenone as...

Polyethylene glycol 400 cysteine adducts of a-, -unsaturated aldehydes as dansyl hydrazones stabilization and enhancement dipping solution, 25% in chloroform [268]... 

Polyethylene glycol 4000 cetanol after reaction with 8-bromomethyl-benzo-d-pyndo( 1,2-a)pynmidin-6-one stabilization > 15 d dipping solution, 10% in chloroform [291]... 

Triton X-100 testosterone dansyl hydrazone > 25-fold dipping solution, 20% in chloroform [232]... 

Dipping solution Dissolve 2 g antimony(III) chloride in 50 ml chloroform. 

Dipping solution II Mix chloroform, paraffin oil and triethanolamine in the ratio of6- -l- -l. 

Dipping solution Dissolve 0.1 g 2,6-dibromoquinone-4-chloroimide in 10 ml dimethyl sulfoxide saturated with sodium hydrogen carbonate. Then make up to 100 ml with chloroform. 

Dipping solution Dissolve 5 g trichloroacetic acid in 50 ml chloroform [2] or ethanol. 

Dipping solution Dilute 1 ml stock solution to 100 ml with chloroform. 

Dipping solution Dissolve 10 g trichloroacetic acid and 0.4 g chloramine T (N-chloro-4-methylbenzenesulfonamide sodium salt) in a mixture of 80 ml chloroform, 18 ml methanol and 2 ml water [11]. 

Detection and resnlt The chromatogram was freed from mobile phase for 5 min in a stream of cold air, immersed twice in the dipping solution for 2 s and then dried for 5 min in a stream of cold air. In order to stabilize and enhance the fluorescence intensity it was then immersed twice for 2 s in a solution of Triton X-100 — chloroform (1+4), with the chromatogram being kept in the dark between and after these dipping processes. 

Note The reagent can be employed on silica gel, kieselguhr. Si 50 000 and RP layers [6]. The fluorescence intensities of the chromatogram zones can be increased by dipping in a solution of liquid paraffin in hexane or chloroform [8,11]. 

Teflon support with its glass side facing the gas inlet the autoclave was evacuated (10 min, < 1 mbar), carefully filled with HCl gas (1 bar) and heated to 110°C for 15 min. After opening the autoclave the HCl vapors were blown out with a stream of cold air (5 min) and the HPTLC plate was cooled to room temperature. In order to intensify and stabilize the fluorescence the plate was dipped in a solution of liquid paraffin in chloroform (30 + 70) for 15 s. 

The fluorescence was stabilized and enhanced by a factor of 30 by dipping into a solution of liquid paraffin — chloroform — triethanolamine (10 - - 60 -I- 10). 

Detection and result The chromatogram was dried in a stream of warm air for 1 min, after cooling it was immersed for 1 s in the reagent solution. After redrying in a stream of warm air it was dipped into a mixture of chloroform — liquid... 

The distillation should be carried out carefully at first until all the chloroform has distilled. A distilling adapter dipping just below the surface of the acid solution should be used in order to minimize loss of cyclobutylamine. Care must be taken that the basic solution in the distillation flask which still contains sodium azide does not come in contact with the hydrochloric acid solution in the receiver. 

Induced fluorescence (X, > 430 nm, cut off filter) by thermal treatment of the chromatogram, the fluorescence increased by a factor of 2.5 by dipping in a solution of Triton X-100 — chloroform (1+4). Working range 2-50 ng substance per chromatogram zone. Prewashing the layers with methanol-ammonia solution (25%) (50+ 50) increased the precision. 

Detection and result The dried chromatogram was heated in the drying oven at 180 °C for 20 min. After cooling to room temperature it was dipped twice for 1 s into a solution of Triton X-100 — chloroform (l-t-4) which stabilized the fluorescence and increased its intensity by a factor of 2.5. Between the two dipping steps the chromatogram was air-dried in the dark for 30 min until the chloroform had completely evaporated. 

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