Amylose composition

Fig. 15 UV-VIS spectra of a PANIs/SPG composite (black line) and PANIs/amylose composite (gray line) after doping, b After 24 h under the same condition and c Photo image of PANIs/SPG composite aqueous solution after doping. Reprinted with permission from [97]...

Ikeda M, Furusho Y, Okoshi K, Tanahara S, Maeda K, Nishino S, Mori T, Yashima E (2(K)6) A luminescent poly(phenylenevinylene)-amylose composite with supramolecular liquid crystallinity. Angew Chem Int Ed 45 6491-6495... 

Young, A. H., 1967, Polyvinyl alcohol plasticized amylose compositions. US Pat. 3,312,641. 

Cellulose and amylose derivative CSPs are mostly used, in the normal-phase mode, with n-hexane-based mobile phases containing some alcohol as modifier. Chromatographic performances, retention and selectivity, are reported to be affected by the composition of the mobile phase... 

The composition of branched building blocks in the isolated clusters of the amylose-free potato starch, was analyzed by treating the clusters with excess a-amylase (Bertoft, 2007b). Under such conditions, the enzyme is forced to continue the attack at internal chains shorter than 9 residues inside the clusters. As a resultthe building blocks, which practically resist further attack... 

Senti and Witnauer1 have provided the only information yet available on the stoichiometry of formation of polysaccharide adducts. Their studies of addition compounds of amylose in aqueous ethanolic media showed that the combining ratio of D-glucose residue to salt is a function of salt concentration, and that the minimum ratios are approached as the salt concentration is increased. Beyond a certain concentration of salt, the ratio becomes almost constant. The anion plays an important role in determining the magnitude of the minimum ratio for an amylose adduct. Potassium bromide and potassium iodide give adducts of minimum ratio 2 1, whereas potassium acetate and potassium propionate give 1 1 adducts. A study of the composition of the potassium acetate adduct as a function of salt concentration indicated that two, relatively stable adducts are formed, the 1 1 and the 2 1. 

A second very widely distributed polysaccharide is starch, which is stored in the seeds, roots, and fibers of plants as a food reserve — a potential source of glucose. The chemical composition of starch varies with the source, but in any one starch there are two structurally different polysaccharides. Both consist entirely of glucose units, but one is a linear structure (amylose) and the other is a branched structure (amylopectin). 

In sub-FC, a detailed study of the influence of mobile phase additives on the chiral resolution of isoxazoline-based Ilb/IIIb receptor antagonists was carried out by Blackwell [145] on Chiralcel OD-H CSPs. The different mobile phase additives used were acetic acid, trifluoroacetic acid, formic acid, water, triethylamine, triethanolamine, n-hexylamine, trimethyl phosphate, and tri-w-butyl phosphate. In general, n-hexylamine and tri-/ -butyl phosphate mobile phase additives resulted in better resolution. The chiral separation of four 1,3-dioxolane derivatives on an amylose-based column has been described [151]. The effects of mobile phase composition, temperature, and pressure have been investigated. The nature of the modifier is the main parameter it has the highest impact on chiral resolution and is more important than the polarity of the mobile phase. Therefore, the organic modifier that gave the best enantiomeric separation was different for each compound. 

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