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We report molecular dynamics simulations showing that a DNA molecule could be spontaneously inserted into carbon nanotube (CNT) in a water solute environment. The van der Waals and hydrophobic forces were found to be important for the insertion process, with the former playing a more dominant role in the DNA−CNT interaction. Our study suggests that the encapsulated CNT−DNA molecular complex can be further exploited for applications such as DNA modulated molecular electronics, molecular sensors, electronic DNA sequencing, and nanotechnology of gene delivery systems.

Nanostructured viruses are attractive for use as templates for ordering quantum dots to make self-assembled building blocks for next-generation electronic devices. So far, only a few types of electronic devices have been fabricated from biomolecules due to the lack of charge transport through biomolecular junctions. Here, we show a novel electronic memory effect by incorporating platinum nanoparticles into tobacco mosaic virus. The memory effect is based on conductance switching, which leads to the occurrence of bistable states with an on/off ratio larger than three orders of magnitude. The mechanism of this process is attributed to charge trapping in the nanoparticles for data storage and a tunnelling process in the high conductance state. Such hybrid bio-inorganic nanostructures show promise for applications in future nanoelectronics.

In real life applications, supercapacitors (SCs) often can only be used as part of a hybrid system together with other high energy storage devices due to their relatively lower energy density in comparison to other types of energy storage devices such as batteries and fuel cells. Increasing the energy density of SCs will have a huge impact on the development of future energy storage devices by broadening the area of application for SCs. Here, we report a simple and scalable way of preparing a three-dimensional (3D) sub-5 nm hydrous ruthenium oxide (RuO2) anchored graphene and CNT hybrid foam (RGM) architecture for high-performance supercapacitor electrodes. This RGM architecture demonstrates a novel graphene foam conformally covered with hybrid networks of RuO2 nanoparticles and anchored CNTs. SCs based on RGM show superior gravimetric and per-area capacitive performance (specific capacitance: 502.78 F g−1, areal capacitance: 1.11 F cm−2) which leads to an exceptionally high energy density of 39.28 Wh kg−1 and power density of 128.01 kW kg−1. The electrochemical stability, excellent capacitive performance, and the ease of preparation suggest this RGM system is promising for future energy storage applications.

We demonstrate the use of surface Zeta potential measurements as a new tool to investigate the interactions of iron oxide nanoparticles and cowpea mosaic virus (CPMV) nanoparticles with human normal breast epithelial cells (MCF10A) and cancer breast epithelial cells (MCF7) respectively. A substantial understanding in the interaction of nanoparticles with normal and cancer cells in vitro will enable the capabilities of improving diagnostic and treatment methods in cancer research, such as imaging and targeted drug delivery. A theoretical Zeta potential model is first established to show the effects of binding process and internalization process during the nanoparticle uptake by cells and the possible trends of Zeta potential change is predicted for different cell endocytosis capacities. The corresponding changes of total surface charge of cells in the form of Zeta potential measurements were then reported after incubated respectively with iron oxide nanoparticles and CPMV nanoparticles. As observed, after MCF7 and MCF10A cells were incubated respectively with two types of nanoparticles, the significant differences in their surface charge change indicate the potential role of Zeta potential as a valuable biological signature in studying the cellular Biomed Microdevices

We report the controlled synthesis of multiwalled carbon nanotube−quantum dot (CNT-QD) heterojunctions using the ethylene carbodiimide coupling procedure (EDC). Thiol-stabilized ZnS-capped CdSe quantum dots containing amine terminal groups (QD−NH 2 ) were conjugated with acid-treated multiwalled carbon nanotubes (MWCNT) ranging from 400 nm to 4 µm in length. Scanning and transmission electron microscopy were used to characterize the conjugation process.The unique electrical, mechanical, and chemical properties of carbon nanotubes have made them intensively studied materials in the field of nanotechnology. [1][2][3][4] A number of device applications of these nanoscale materials have been envisioned. [5][6][7][8][9][10] Single-walled carbon nanotubes (SWCNTs) 11 and multiwalled carbon nanotubes (MWCNTs) 12,13 under special conditions have been shown to possess ballistic conduction behavior, which makes them attractive candidates for field-emission devices. 14 SWCNTs indicate either metallic or semiconductor behavior depending on their chirality 15 and radial dimension. 16,17 Although the electronic properties of MWCNTs 18-20 are less well known, they have been shown to exhibit either metallic 19 or semiconducting properties 20 depending on their outermost shell. The intershell interactions in an MWCNT are weak; therefore, electrical transport is confined to the outermost shell. 17 It has been shown recently that it is possible to manipulate the electrical properties of an MWCNT by using current-induced oxidation to break down systematically the outermost shells layer by layer. 21 This opens up the possibility of selecting the tube with the desired electrical property. In addition, doping 8 and the introduction of defects 20 or distortion 22 into the CNTs have also been utilized for manipulating their energy-band structure. The versatile electrical properties of CNTs make them promising candidates for nanoscale electronic devices, 12,14,23,24 especially transistors. 25,26 In most of the previous work on CNT-based nanoscale transistors, control over the electrical

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Magnetic nanoparticles (MNP) with a diameter of 8 nm were modified with different generations of polyamidoamine (PAMAM) dendrimers and mixed with antisense survivin oligodeoxynucleotide (asODN). The MNP then formed asODNdendrimer-MNP composites, which we incubated with human tumor cell lines such as human breast cancer MCF-7, MDA-MB-435, and liver cancer HepG2 and then analyzed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, quantitative reverse transcription-PCR, Western blotting, laser confocal microscopy, and high-resolution transmission electron microscopy. Results showed that the asODN-dendrimer-MNP composites were successfully synthesized, can enter into tumor cells within 15 min, caused marked down-regulation of the survivin gene and protein, and inhibited cell growth in dose-and time-dependent means. No.5 generation of asODN-dendrimer-MNP composites exhibits the highest efficiency for cellular transfection and inhibition. These results show that PAMAM dendrimer-modified MNPs may be a good gene delivery system and have potential applications in cancer therapy and molecular imaging diagnosis.