Sugars Qualitative Organic Analysis

The precipitation of aluminium hydroxide by solutions of sodium hydroxide and ammonia does not take place in the presence of tartaric acid, citric acid, sulphosalicylic acid, malic acid, sugars, and other organic hydroxy compounds, because of the formation of soluble complex salts. These organic substances must therefore be decomposed by gentle ignition or by evaporating with concentrated sulphuric or nitric acid before aluminium can be precipitated in the ordinary course of qualitative analysis. 

The products of enzyme action must not be utilized by the organism this can be ensured by the presence of an excess of a carbon source such as succinate in the culture medium. The results of qualitative and quantitative analysis of the products released can then be used to deduce the arrangement of the sugar residues in the chain. A study of the specificities of the induced enzymes may lead to information on the configuration and mode of linkage of the sugar residues. 

The most useful detection mode in IC seems to be MS. Because of its flexibility, this coupling method has numerous possible applications in ion analysis. IC coupled with spectrometric detector (IC-MS) is a modem determination method for quantitative and qualitative analysis. Similar analytes are separated by IC and subsequently detected by a mass spectrometer. Both ionic substances (anionic and cationic) and polar substances (e.g., organic acids or sugars) can be determined with this very sensitive detection system. 

TLC analysis of agricultural products, foods, beverages, and plant constituents is described by Sherma in a review paper. In laboratories throughout the world, TLC is widely used for food analysis and qualitative control. Numerous applications of TLC have been reported in the area of food composition, involving determinations of compounds such as lipids, sugars, amines, vitamins, and organic acids such as amino acids and fatty acids. 

With the advent of new, more versatile and more robust LC-MS interfaces based on atmospheric-pressure ionization, the use of thermospray will rapidly diminish. However, the above-mentioned applications in sugar analysis as well as a large number of other applications in organic ion analysis such as phenoxy-acetic acids [128], quaternary ammonium pesticides [129, 130], anionic surfactants [131, 132], sulfated azo dyes [133, 134], sulfonamides [135], and ff-lactam antibiotics [136, 137] have proved the potential of this coupling technique in qualitative and quantitative analysis. 

---