To facilitate combined doxorubicin and photothermal treatments, we developed doxorubicin-loaded poly(lactic-co-glycolic acid)-gold half-shell nanoparticles (DOX-loaded PLGA-Au H-S NPs) by depositing Au films on DOX-loaded PLGA NPs. As the PLGA NPs biodegraded, DOX was released, and heat was locally generated upon near-infrared (NIR) irradiation due to NIR resonance of DOX-loaded PLGA H-S NPs. Compared with chemotherapy or photothermal treatment alone, the combined treatment demonstrated a synergistic effect, resulting in higher therapeutic efficacy and shorter treatment times. Since our NPs selectively deliver both heat and drug to tumorigenic regions, they may improve the therapeutic effectiveness with minimal side effects.

We report direct measurements of electrical transport through poly(dA)-poly(dT) and poly(dG)-poly(dC) DNA molecules containing identical base pairs. The observed experimental results suggest that electrical transport through DNA molecules occurs by polaron hopping. We have also investigated the effect of gate voltage on the current-voltage curve. It demonstrates the possibility of a DNA field-effect transistor operating at room temperature. Moreover, the gate-voltage dependent transport measurements show that poly(dA)-poly(dT) behaves as an n-type semiconductor, whereas poly(dG)-poly(dC) behaves as a p-type semiconductor.

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We have developed RGD-attached gold (Au) half-shell nanoparticles containing methotrexate (MTX) for the treatment of rheumatoid arthritis (RA), where MTX is the most widely used disease-modifying anti-rheumatic drug (DMARD) for the treatment of RA, and RGD peptide is a targeting moiety for inflammation. Upon near-infrared (NIR) irradiation, heat is locally generated due to Au half-shells, and the drug release rate is enhanced, delivering heat and drug to the inflamed joints simultaneously. RA is a chronic inflammatory disease characterized by synovial inflammation in multiple joints within the penetration depth of NIR light. When combined with NIR irradiation, these nanoparticles containing a much smaller dosage of MTX (1/930 of MTX solution) showed greater therapeutic effects than that of a conventional treatment with MTX solution in collagen-induced arthritic mice. This novel drug delivery system is a good way to maximize therapeutic efficacy and minimize dosage-related MTX side effects in the treatment of RA. Furthermore, these multifunctional nanoparticles could be applied to other DMARDs for RA or other inflammatory diseases.

The contact resistance between a carbon nanotube and metal electrodes decreases by several orders of magnitude and becomes long-term stable when the nanotube contacted by Ti-Au electrodes was annealed by a rapid thermal annealing method at 600-800 °C for 30 s. The contact resistances of the annealed samples are in the range 0.5-50 kΩ at room temperature, depending on the electrical properties of the nanotube. The short and relatively low-temperature annealing process enables us to make a surface Ti-nanotube contact suitable for electrical measurements. For the samples with relatively low contact resistances (0.5-5 kΩ) at room temperature, the contact resistance remained constant or decreased slightly as the temperature was lowered. Those with a relatively high contact resistance (5-50 kΩ), on the other hand, showed increasing contact resistance with a lowering of the temperature.

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Core–multishell nanoparticles: Near‐IR‐resonant rhodamine‐encapsulated poly(lactic‐co‐glycolic acid) (PLGA)–Mn/Au half‐shell nanoparticles (NPs; see figure) are developed by depositing metal multilayers on PLGA NPs. These NPs can be used for photothermally controlled drug delivery and magnetic resonance imaging. Upon NIR irradiation, the release rate of rhodamine from the PLGA NPs is about twice as great as that without NIR irradiation, indicating photothermally controlled drug delivery possibilities.