Skip main navigation

Cookies Notification

We use cookies on this site to enhance your user experience. By continuing to browse the site, you consent to the use of our cookies. Learn More
×

System Upgrade on Tue, May 28th, 2024 at 2am (EDT)

Existing users will be able to log into the site and access content. However, E-commerce and registration of new users may not be available for up to 12 hours.
For online purchase, please visit us again. Contact us at customercare@wspc.com for any enquiries.

SEARCH GUIDE  Download Search Tip PDF File

  • articleNo Access

    Magnetotaxis as a Means for Nanofabrication

    Magnetotactic bacteria (MTB), discovered in early 1970s contain single-domain crystals of magnetite (Fe3O4) called magnetosomes that tend to form a chain like structure from the proximal to the distal pole along the long axis of the cell. The ability of these bacteria to sense the magnetic field for displacement, also called magnetotaxis, arises from the magnetic dipole moment of this chain of magnetosomes. In aquatic habitats, these organisms sense the geomagnetic field and traverse the oxic-anoxic interface for optimal oxygen concentration along the field lines. Here we report an elegant use of MTB where magnetotaxis of Magnetospirillum magneticum (classified as AMB-1) could be utilized for controlled navigation over a semiconductor substrate for selective deposition. We examined 50mm long coils made out of 18AWG and 20AWG copper conductors having diameters of 5mm, 10mm and 20mm for magnetic field intensity and heat generation. Based on the COMSOL simulations and experimental data, it is recognized that a compound semiconductor manufacturing technology involving bacterial carriers and carbon-based materials such as graphene and carbon nanotubes would be a desirable choice in the future.

  • articleNo Access

    SPOTLIGHTS

      Cancer Control Efforts in Vietnam: Interview with Dr Tran Thanh Huong.

      Prof. Jackie Y. Ying, a Leader in Nanotechnology.

      Exclusive Interviews with TR Innovators under 35.

    • articleOpen Access

      PSYCHIATRIC INVESTIGATION USING WGMs IN MICRORING CIRCUITS

      The use of an electrical probe is formed by whispering gallery modes (WGMs) of light within the coated microring circuits, in which the electrical signal is generated by trapped electron tunneling along the circular path of the coated microring circuit. The collection of electrons is formed within the WGMs, where in this study, a modified nonlinear microring resonator known as a PANDA ring resonator is coated by gold material and forms the mirroring circuit. The induced current (magnetic field) within the circuit occurs by the coupling effects between trapped electrons and coated ring, which can penetrate into the brain cells and transform to the required signals via the terahertz carrier for psychiatric investigations. The use of WGMs for 3D image construction using a PANDA conjugate mirror is also discussed, which is useful for thermal and imaging sensors.

    • chapterNo Access

      MOLECULAR SELF-ASSEMBLY: A TOOLKIT FOR ENGINEERING AT THE NANOMETER SCALE

      Among the many challenges facing the development of a molecular-based nanotechnology, the directed assembly of discrete molecular objects, and their controlled integration into macroscopic structures, is fundamental. The selective self-assembly or self-organizing characteristic inherent to certain molecules, for example DNA, is a property that could be exploited to address these challenges. This integration problem can be separated into more fundamental tasks: attaching molecular anchors to the macroscopic structures with high spatial resolution; assembling the discrete molecular objects; and positioning and attaching the molecular objects onto the macroscopic structures.

      Here, several aspects of these tasks will be discussed, for example using short DNA molecules as molecular anchors and their attachment to electrodes separated by a few ten nanometers; the generation of branched DNA complexes by molecular self-organization; and using AC electric fields for the manipulation, orientation, and positioning of DNA molecules.