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Toshifumi Takeuchi

Publications and source records attributed to Toshifumi Takeuchi.

22 records · Page 2Linked to original sources

Novel strategy for molecular imprinting of phenolic compounds utilizing disulfide templates.

A molecularly imprinted polymer was synthesized by using allyl phenyl disulfide as a template. The mixture of allyl phenyl disulfide, divinylbenzene, and 2,2'-azobis(isobutyronitrile) in chloroform was polymerized by UV irradiation for 24 h at 5 degrees C and further 3 h at 80 degrees C. The disulfide bonds of the resulting polymer were reductively cleaved by NaBH(4) in methanol to give thiol groups in the binding sites. The polymer selectively recognized phenol rather than thiophenol. In chromatographic study using polymer-packed columns, the retention factor of the IP for phenol was 5.60 and that of a reference polymer was 4.20. The higher retention for phenol was supported by ab initio calculation.

Disulfides↗

Post-oxidative conversion of thiol residue to sulfonic acid in the binding sites of molecularly imprinted polymers: disulfide based covalent molecular imprinting for basic compounds.

An imprinted polymer using a disulfide derivative as a template was treated with NaBH4 to yield the polymer with thiol groups in the binding sites. The thiol groups were then oxidized with H2O2/AcOH to yield the molecularly imprinted polymer with sulfo groups in the binding sites. This site conversion can provide amine-imprinted polymers, in which amine is retained to the imprinted polymer by the strong electrostatic interaction between the amino group and the sulfo group in the binding sites.

Journal Article↗

Molecular recognition by indoleacetic acid-imprinted polymers--effects of 2-hydroxyethyl methacrylate content.

Molecularly imprinted polymers for indole-acetic acid were prepared by co-polymerizing N,N-dimethylaminoethyl methacrylate, 2-hydroxyethyl methacrylate (HEMA), and ethylene glycol dimethacrylate. The dependence of the affinity and selectivity of the imprinted polymers on HEMA content was evaluated chromatographically. The affinity was improved by increasing the HEMA content; the selectivity of the imprinted polymer was best when the HEMA content was approximately 30%, irrespective of monomer content.

Biosensing Techniques↗