Matsuhiko Nishizawa

Membranes containing cylindrical metal nanotubules that span the complete thickness of the membrane are described. The inside radius of the nanotubules can be varied at will; nanotubule radii as small as 0.8 nanometer are reported. These membranes show selective ion transport analogous to that observed in ion-exchange polymers. Ion permselectivity occurs because excess charge density can be present on the inner walls of the metal tubules. The membranes reject ions with the same sign as the exces

A microneedle array is an attractive option for a minimally invasive means to break through the skin barrier for efficient transdermal drug delivery. Here, we report the applications of solid polymer-based ion-conductive porous microneedles (PMN) containing interconnected micropores for improving iontophoresis, which is a technique of enhancing transdermal molecular transport by a direct current through the skin. The PMN modified with a charged hydrogel brings three innovative advantages in iont

Tubules of 200 nm outer diameter spinel were prepared by thermal decomposition of an aqueous solution containing lithium nitrate and manganese nitrate at 1:2 molar ratio using a nanoporous alumina membrane as a template. After dissolving the template membrane, the resulting nanotubule array of was coated with polypyrrole to investigate the galvanostatic charge‐discharge characteristics. The polypyrrole‐coated tubule electrodes exhibited higher capacities than the polypyrrole‐coated thin‐film ele

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTPenicillin sensor based on a microarray electrode coated with pH-responsive polypyrroleMatsuhiko. Nishizawa, Tomokazu. Matsue, and Isamu. UchidaCite this: Anal. Chem. 1992, 64, 21, 2642–2644Publication Date (Print):November 1, 1992Publication History Published online1 May 2002Published inissue 1 November 1992https://pubs.acs.org/doi/10.1021/ac00045a030https://doi.org/10.1021/ac00045a030research-articleACS PublicationsRequest reuse permissionsArticle Vi

Hydrogel-based, molecular permeable electronic devices are considered to be promising for electrical stimulation and recording of living tissues, either in vivo or in vitro. This study reports the fabrication of the first hydrogel-based devices that remain highly electrically conductive under substantial stretch and bending. Using a simple technique involving a combination of chemical polymerization and electropolymerization of poly (3,4-ethylenedioxythiophene) (PEDOT), a tight bonding of a cond

Wound healing on skin involves cell migration and proliferation in response to endogenous electric current. External electrical stimulation by electrical equipment is used to promote these biological processes for the treatment of chronic wounds and ulcers. Miniaturization of the electrical stimulation device for wound healing on skin will make this technology more widely available. Using flexible enzymatic electrodes and stretchable hydrogel, a stretchable bioelectric plaster is fabricated with

The micropatterns of mammalian cells (HeLa cells) were prepared on glass substrates, and the respiration of the patterned cells was studied by microelectrode techniques, mainly by scanning electrochemical microscopy (SECM). The cellular patterns on a micrometer scale were prepared by microcontact printing of an extracellular matrix protein, fibronectin, onto a hydrophobic glass plate. The oxygen concentration in the vicinity of the patterned cells was mapped by scanning a Pt microelectrode, and

A completely organic iontophoresis patch is reported. A built-in biofuel cell is mounted on the patch that generates transdermal iontophoretic administration of compounds into the skin. The amplitude of transdermal current is tuned by integrating a conducting polymer-based stretchable resistor of predetermined resistance. As a service to our authors and readers, this journal provides supporting information supplied by the authors. Such materials are peer reviewed and may be re-organized for onli

We report a porous polymer microneedle array with continuous micropores that has high mechanical strength and water absorption speed.

The solid‐state diffusion of lithium ion in carbon was directly investigated in single spherical particles of graphitized mesocarbon microbeads (MCMB, Osaka Gas Co.). In order to achieve electrochemical measurements focusing on a single particle, a molybdenum‐filament microelectrode was maneuvered to make electrical contact with a single MCMB placed in an organic solvent mixture containing lithium ions as an electrolyte. This novel microelectrode technique gives electrochemical information about

Electrodeposition of Cu on an Au(111)/mica electrode surface coated with a self-assembled monolayer (SAM) of propanethiol has been studied in a potential region comprising the underpotential deposition (UPD). The UPD of Cu and stripping of the deposited Cu took place reversibly through the SAM layer, and furthermore it was found that the SAM was still present on the electrode surface without significant changes in its amount and structure even after repeating Cu deposition/stripping cycles. The

We have developed gel sheet-supported C(2)C(12) myotube micropatterns and combined them with a microelectrode array chip to afford a skeletal muscle cell-based bioassay system. Myotube line patterns cultured on a glass substrate were transferred with 100% efficiency to the surface of fibrin gel sheets. The contractile behavior of each myotube line pattern on the gel was individually controlled by localized electrical stimulation using microelectrode arrays that had been previously modified with