Contaminants branch method

A chloroform-water mixture is the extraction solvent for the contaminants branch (CB) method, proposed by Eppley (36). The CB method has been adopted by the Association of Official Analytical Chemists as the official method for determination of aflatoxins in groundnuts and their byproducts (17). 

Table III shows the results of chemical analyses of amylose samples compared, where possible, with values of Mn. These indicate the presence of more than one nonreducing, terminal group in some of the amylose samples. In the case of potato starch, this result is thought to be attributable to the presence of contaminating amylopectin rather than to inherent branching in the molecule.106 Other methods of examining the fine structure of amylose, and the question of branching, will be dealt with later (see p. 381).

Nonylphenol, a product of Union Carbide, Canada Ltd., consists of a mix of p-substituted monoalkyl nonypbenols, (randomly branched), with approximately 3% of the o-isomer and 4% dinonyl-phenol also represent. Apart from Dowanol, all the adjuvants mentioned contain minor variable amounts of undefined contaminants which are a function of the well head source and batch from which they were distilled (Aerotex, Cyclosol) or the method of synthesis (Atlox and nonylphenol). These chemicals and related compounds are also widely used in a wide range of household products including detergents, cleaners, shampoos, foods and other consumer and commercial products. 

The use of synthetic materials in biomedical applications has increased dramatically dining the past few decades. Surface properties of polymers are of fundamental importance in many branches of industrial applications (e.g., separation of gasses, liquid mixtures, bonding, coating, adhesion, etc.). Performances of membranes also depend on the properties of their surfaces, since membrane performance is strongly influenced by the surface phenomena. Hence, it is very natural that much attention has been paid to the membrane surface modification. Surface contamination which may lead to deterioration in membrane performance is also known to be governed by the membrane surface properties. Detailed methods for modification of synthetic membranes are discussed by Khulbe et al. [63]... 

Pure enzymes are highly specific and only hydrolyze one type of interglyco-sidic linkage. This affords a valuable method for the identification of a particular t) of linkage, and is useful in studies of branched-chain polysaccharides, since the hydrolysis halts at the branch point. Care must, however, be exercised in the interpretation of results of studies made with crude enz3une preparations, since contaminating enzymes may permit a wide range of other reactions to yield untrustworthy results and vitiate the specificity of the pure enzyme. 

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