Application of a thermalin situ reaction for fluorimetric detection of carbohydrates on NH2-layers

Carbohydrates

“…Sugars are readily converted, leading to stable, intensely fluorescing derivatives. The thermal treatment, after development, does not lead to a discoloration of the chromatograms as is often the case with chemical postchromatographic derivatization (56). A disadvantage of the aminopropyl-modified silica gel layer is the tendency for glycosylamine to form between reducing sugars and the amino groups on the stationary phase (32).…”

“…Chromatographic properties of amino-silica gel layers are similar to those of nonmodified silica gel, and some identical solvent systems can be used with both sorbents ( Table 6). The main advantage of amino-bonded silica is that it affords simple detection of separated sugars by a thermal in situ reaction (56)(57)(58)(59). Sugars are readily converted, leading to stable, intensely fluorescing derivatives.…”

“…Amino groups added as aminopropyl groups bonded to silica gel, or simply as amino-silica gel (NH 2 -silica gel), are particularly useful as sorbent modifications for carbohydrate analysis (32, 56). As is the case with other polar bonded phases, such sorbents can be used in either the normalphase or reversed-phase mode.…”

“…Heating the developed plate to approximately 150°C for 3-4 min converts the separated sugars into stable, fluorescing derivatives with a practically unlimited life (56). Longer activation time is necessary for nonreducing di-and trisaccharides.…”

Determination of the Mycotoxin, Sterigmatocystin, by Thin‐Layer Chromatography and Reagent‐Free Derivatisation

“…[18] A simple and effective method was developed for fluorometric detection of glucose, fructose, and other carbonylic compounds after TLC separation on amino-silica gel. [19] A reagent-free derivatisation procedure was also successfully applied for fluorescence induction in various carbohydrates, [20] uric acid, and creatinine [21] or catecholamines. [22] Therefore, the aim of this paper was to develop a simple TLC-based method with reagent-free derivatisation, suitable for routine analysis of sterigmatocystin at levels of interest in the lower mg/kg range.…”