Amylose was prepared by enzymatic polymerization of alpha-D-glucose 1-phosphate dipotassium catalyzed by a phosphorylase using two kinds of the primers derived from maltopentaose, and then it was chemically bonded to silica gel to be used as a chiral stationary phase (CSP) in high-performance liquid chromatography. In method I, maltopentaose was first lactonized and allowed to react with (3-aminopropyl)triethoxysilane to form an amide bond. Amylose chains with a desired chain length and a narrow molecular weight distribution were then constructed by the enzymatic polymerization. The resulting amylose bearing a trialkoxysilyl group at the terminal was allowed to react with silica gel for immobilization. In method II, maltopentaose was first oxidized to form a potassium gluconate at the reducing terminal. After the enzymatic polymerization was performed with the potassium gluconate, the amylose end was lactonized to be immobilized to 3-aminopropyl-silanized silica gel through amide bond formation. Two amylose-conjugated silica gels thus obtained were treated with a large excess of 3,5-dimethylphenyl isocyanate to convert hydroxy groups of amylose to corresponding carbamate residues. The CSP derived through method II was superior in chiral recognition to the CSP derived from method I and showed better resolving power and higher durability against solvents such as tetrahydrofuran compared with a coated-type CSP. Influences of degree of polymerization of amylose, the spacer length between amylose and silica gel, and mobile phase compositions on chiral recognition were investigated.

The objective of our research was to prepare novel conjugates between polysaccharides and vinyl polymers by applying enzymes as polymerization catalyst for polysaccharide synthesis. An approach was attained using amylose-substituted styrene macromonomers (vinylbenzyl amylose amide, VAA; the number-average degree of polymerization of amylose = 24 and 150) which were synthesized from maltopentaose-substituted styrene (VM5A) by phosphorylase-catalyzed polymerization of glucose 1-phosphate. Radical homo- and copolymerization of VAA gave an uncommon type of graft copolymers consisting of polystyrene and polyacrylamide backbones and amylose side chains of uniform length. Water-insoluble amylose was solubilized into water by incorporating VAA units into polyacrylamide main chains and also by hydroxypropylation of the amylose moieties of water-insoluble copolymers. Structural features of these graft copolymers were discussed on the basis of amylose−iodine complexation investigated by UV spectroscopy. Schematic structures of two different types of polystyrene-graft-amylose prepared via homopolymerization of VAA and via enzymatic elongation from poly(VM5A) were proposed. These amylose-carrying polyacrylamide and polystyrene prepared by applying enzyme-catalyzed polymerization are of interest as a new type of biomedical material and a well-defined model for conformational analysis.

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The polycrystalline silicalite membrane was prepared on a porous sintered stainless steel support and its pervaporation performance was investigated using an acetic acid / water mixture as a feed. The silicalite membrane selectively permeates acetic acid in the concentration of the feed acetic acid in the region of 5 to 40 vol%.