Spray solutions

D) Spraying solution. A solution of 0-2 g. of ninhydrin in a mixture of 99 ml. of redistilled n-butanol and i ml. of glacial acetic acid. 

Nicotine is used as a contact insecticide for aphids attacking fmits, vegetables, and ornamentals, and as a fumigant for greenhouse plants and poultry mites. Nicotine sulfate is safer and more convenient to handle and the free alkaloid is rapidly Hberated by the addition of soap, hydrated lime, or ammonium hydroxide to the spray solution. Nicotine sprays commonly contain 0.05—0.06% nicotine, and nicotine dusts, 1—2% nicotine. 

The dipping solutions described in Part II of this book are usually less concentrated than the corresponding spray solutions. The solvents employed are specially chosen for their suitability to the special requirements of dipping solutions. Water, which on the one hand, can sit on the surface of RP plates and not penetrate them and, on the other hand, can cause disintegration of water-incompatible layers is usually replaced by alcohol or other lipophilic solvents. 

Liquid paraffin benzo(a)pyrene 35-fold spray solution, 67% in n-hexane the fluorescence is stable for more than 10 h [245]... 

Liquid parafTin selenium as 2,1,3-naphthoselenodiazole 25-fold spray solution, 67% m n-hexane (Fig 53 [240])... 

Liquid paraffin carbamate and urea herbicides stabilization and enhancement spray solution, 20% in toluene, water investigation [241]... 

Liquid paraffin luteoskynn, rugulosin stabilization spray solution, 50% in toluene—ethyl acetate — formic acid (16-1-4-1-1) [244]... 

Glycerol ethoxyquin, dansyl amides 20-fold spray solution, 33% in methanol [292] or 50% ethanol [245]... 

Polyethylene glycol 4000 alcohols, amines stabilization and enhancement spray solution, 50% in methanol, best results on silica gel [271]... 

Triton X-100 dansyl amides and amino acids 30 to 110-fold spray solution, 20% in chloroform [265, 290]... 

Triton X-100 ethoxyquin (antioxidant in spices) > 200-fold, stabilization > 15 h spray solution, 33% in benzene the fluorescence of aflatoxin Bi is reduced by 10 to 15% [292]. 

Spray solution A 0.25% [3] or saturated solution of alizarin [4] in ethanol. 

The dipping solution and spray solution 1 can be stored in the refrigerator for about 1 week. 

Spray solution For sugars [3] dissolve 3 g 2-aminodiphenyl in 100 ml glacial acetic acid and add 1.5 ml 85% orthophosphoric acid. 

Note The dipping solution, which can also be used as a spray solution, can be employed with silica gel, kieselguhr, cellulose, RP, NH2 and CN phases. Sugars (exceptions include, for example, fructose, melezitose and raffinose) yield brilliantly colored zones on an almost colorless background when the spray solution is employed. Aldohexoses appear brown, aldopentoses bright red and hexuronic acids orange in color [3]. The detection limit differs for different substances it ranges from 10 ng (pyridoxal) over 100 ng (cinnamaldehyde) up to 2 pg (citral). 

Spray solution Dissolve 0.5 g 4-aminohippuric acid in 100 ml ethanol. 

The well-dried chromatogram (1 h at 105°C if acidic or basic eluents have been employed) is immersed in the dipping solution for 1 s or homogeneously sprayed with the spray solution and then dried in a stream of cold air. Acids yield blue zones on a colorless or pale blue background [1] which gradually darkens. 

For the detection of ampicillin it is necessary to add acetic acid to the dipping or spray solution. Ampicillin then yields pale zones on a blue background [2]. 

Spray solution Dissolve 1 to 2 g diphenylamine and 1 to 2 ml aniline in 80 ml methanol or ethanol. After addition of 10 ml phosphoric acid make up to 100 ml with methanol [3, 9] or ethanol [7]. 

The chromatogram is freed from mobile phase and evenly sprayed with the spray solution or immersed for 1 s in the dipping solution. After drying the TLC plate is heated to 85 —120°C normally for 10 to 15 min but in exceptional cases for 60 min. It is advisable to observe the chromatogram during the reaction period, because the temperature and duration of heating strongly affect color development. 

Spray solution Dissolve 0.9 ml anihne and 1.66 g phthahc acid in 100 ml water-saturated 1-butanol [1]. 

Spray solution Dissolve 100 mg of 8-anilinonaphthalene-l-sulfonic acid ammonium salt in 100 ml water [1]. 

Spray solution For glycolipids Carefully add 72 ml cone, sulfuric acid to 28 ml water with cooling. Dissolve 50 mg anthrone in the mixture with gentle warming [5]. 

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