Aluminium oxide reagent

Composition materials ineluding indieator reagent and bearer have been investigated as sensor materials. It has been found out that nature of beai er (sorbent or polymer film) is of the main signifieanee. Siliea gel, aluminium oxide, porous glass, polyurethane, polyvinylehloride ete have been investigated as beai ers. 

Aluminium fluoride (anhydrous) [7784-18-4] M 84.0, m 250°. Technical material may contain up to 15% alumina, with minor impurities such as aluminium sulfate, cryolite, silica and iron oxide. Reagent grade AIF3 (hydrated) contains only traces of impurities but its water content is very variable (may be up to 40%). It can be dried by calcining at 600-800° in a stream of dry air (some hydrolysis occurs), followed by vacuum distn at low pressure in a graphite system, heated to approximately 925° (condenser at 900°) [Henry and Dreisbach J Am Chem Soc 81 5274 1959]. 

It is known that not all reactions proceed in the same manner on all adsorbent layers because the material in the layer may promote or retard the reaction. Thus, Ganshirt [209] was able to show that caffeine and codeine phosphate could be detected on aluminium oxide by chlorination and treatment with benzidine, but that there was no reaction with the same reagent on silica gel. Again the detection of amino acids and peptides by ninhydrin is more sensitive on pure cellulose than it is on layers containing fluorescence indicators [210]. The NBP reagent (. v.) cannot be employed on Nano-Sil-Ci8-100-UV2S4 plates because the whole of the plate background becomes colored. 

The reagent may be employed on silica gel, kieselguhr, aluminium oxide, cellulose and polyamide layers. 

Note The dipping solution can also be sprayed on. The detection of the aromatic acids is best performed on cellulose layers, if ammonia-containing mobile phases have been employed. The reagent can also be employed on silica gel, aluminium oxide, RP 18 and polyamide layers. 

Note Indoles, that are substituted with oxygen in position 2 or 3, do not react [11]. The reagent can be employed on silica gel, kieselguhr and Si 50 000 layers. Aluminium oxide layers are not suitable [3]. 

The reagent, which can also be employed to impregnate the layer before chromatography, is best suited for silica gel layers [4] it can, however, also be employed on aluminium oxide, kieselguhr. Si 50000, cellulose and polyamide layers [4]. 

First spray the dried chromatogram homogeneously with reagent 1. Then remove excess reagent in a stream of cold air in the fume cupboard (ca. 30 min for silica gel and 3 h for aluminium oxide layers). Then spray the chromatogram lightly with reagent 2. 

The reagent can be employed on aluminium oxide, silica gel, kieselguhr and Si 50000 layers. 

The reagent can be used, for example, on aluminium oxide and on cellulose layers. 

The reagent can be used on silica gel, kieselguhr. Si 50000, aluminium oxide and cellulose layers. 

The reagent can be employed, for example, on aluminium oxide, silica gel, silver nitrate impregnated silica gel, kieselguhr. Si 50000 and cellulose layers RP and CHIR phases are also suitable. 

The reagent can be used, for example, on silica gel, kieselguhr and Si 50000 layers as well as on aluminium oxide, cellulose or chiral layers. Neither do difficulties occur on RP 18, Diol, NHj and CN phases. Silver nitrate- [4] and calcium oxalate-impregnated layers [9] are also suitable. However, polyamide phases are colored yellow. 

Note The reagent can be just as successfully employed on silica gel, kieselguhr, aluminium oxide and polyamide layers as it can with RP and NH2 phases. The final treatment with ammonia vapor to decolorize the background can be omitted in the last case. 

The reagent can be employed on sihca gel, kieselguhr. Si 50 000 and aluminium oxide layers. 

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