Sulphonated amphoterics

Anionic (sulphate or sulphonate) Amphoteric excluding betaine (WW) Quaternary ammonium salt Betaine, amine, amine oxide Sulphobetaine with strongly basic N Nonionic... 

Sulphate and sulphonate analogues of the carboxylates, such as the sulphobetaine 9.58, can also be used as amphoteric agents. 

Pickling and plating bath Phosphate esters Fatty acid sulphonates Alkanolamides Complex amphoterics Wetting agents... 

These TLC plates have cation- or anion-exchange resins bonded to their surfaces. The resins are materials such as styrene-divinylbenzene copolymers having either quaternary ammonium or sulphonic acid groupings for ion exchange. They are particularly usefril for substmices of high molecular weight and for amphoteric materials. Strong acids or alkalis are usually used as mobile phases. 

Biological interfaces, the surfaces of, for example, proteins, biomembranes, and biological cells in contact with an aqueous solution, often carry carboxyl, amino, phosphate, sulphonate, and imidazole groups. All these groups associate/dissociate with protons. As both cationic and anionic groups are usually present, most biological surfaces are amphoteric. 

Anionics and any other surfactant present. Combine the two columns already described, in the order given. The first column retains sulphates and sulphonates, the second retains the amphoterics, and all other species pass through. Elute as before. 

In this study, the effects of the detergents Ufasan 65 (a linear alkylbenzene sulphonate (LAS), anionic), Triton X-100 (iso-octylphenoxypolyethoxyethanol, non-ionic) and TEGO-Betain L7 (an amphoteric betaine) on the sterol composition of P, purpureum were assessed using lipid fractionation techniques and GLC. The detergent concentrations used were 5-30 ppm. The main characteristics of the detergents used have been listed earlier (2). 

A detailed classification of the chemical compounds usually employed was given by (Dubief et al., 2005). The most important of these are organic acids (carboxylic acids and aromatic sulphonic acids), fatty compounds and their derivatives (fatty acids, fatty alcohols, natural triglycerides, natural waxes, fatty esters, oxyethylenated and oxypropy-lenated waxes, partially sulphated fatty alcohols, lanolin and its derivatives, ceramides), vitamins (A, B and E) (see Section 8.6), protein derivatives (extracts or hydrolysates of keratin, collagen and vegetable proteins), silicones (dimethicone and others), cationic surfactants, cationic polymers, amphoteric and betainic polymers. 

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