Biomedical subjects

Takashi Mukawa

Publications and source records attributed to Takashi Mukawa.

4 recordsLinked to original sources

PubMed2006

Dopamine selective molecularly imprinted polymers via post-imprinting modification.

A novel synthetic dopamine receptor bearing bidentate binding sites were prepared by covalent imprinting using a disulfide linkage which is cleaved and oxidized to a non-covalent sulfoxide recognition group. The used templates have dopamine-like structures connected to an allyl moiety via a disulfide and to a 4-vinylphenyl group via a cyclic boronic diester. After the polymerization, the ester bonds were hydrolyzed and the disulfide bond was reduced to remove the template moiety from the polymer matrix, followed by the oxidation to transform the thiol residues into sulfonic acid (post imprinted process). The imprinted polymer adsorbed dopamine selectively in aqueous solution with the two-point interaction, i.e. the formation of cyclic boronic diester and electrostatic interaction with the sulfonic acid residue.

Biomimetic Materials↗

PubMed2005

Signaling molecularly imprinted polymers: molecular recognition-based sensing materials.

Molecular imprinting is a template polymerization technique that can easily provide synthetic polymers capable of molecular recognition for given target molecules. In addition to their highly specific recognition ability, we are attempting to introduce signaling functions to molecularly imprinted polymers, enabling them to respond according to specific binding events. Some of our work regarding such signaling molecularly imprinted polymers is presented here, including molecularly imprinted polymers that induce spectral shifts of target compounds because of binding. Such compounds include hydrogen-bonding-based fluorescent imprinted polymers and metalloporphyrin-based signaling molecularly imprinted polymers.

Acrylates↗

PubMed2003

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↗

PubMed2002

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↗