Current status and perspectives in atomic force microscopy-based identification of cellular transformation

Chenbo Dong, Xiao Hu, Cerasela Zoica Dinu Department of Chemical and Biomedical Engineering, West Virginia University, Morgantown, WV, USA Abstract: Understanding the complex interplay between cells and their biomechanics and how the interplay is influenced by the extracellular microenvironment, as well as how the transforming potential of a tissue from a benign to a cancerous one is related to the dynamics of both the cell and its surroundings, holds promise for the development of targeted translational therapies. This review provides a comprehensive overview of atomic force microscopy-based technology and its applications for identification of cellular progression to a cancerous phenotype. The review also offers insights into the advancements that are required for the next user-controlled tool to allow for the identification of early cell transformation and thus potentially lead to improved therapeutic outcomes. Keywords: atomic force microscopy (AFM), nanoindentation, malignant transformation, cancerous phenotype, bio-nano-mechanical signatur

Integrated devices based on networks of nanotubes and nanowires

Although advanced devices based on nanotubes (NTs) and nanowires (NWs) are drawing much attention, devices based on a single NT or NW are not suitable for general manufacturing purposes, as it is still extremely difficult to control the electronic properties, growth and alignment of individual NTs or NWs on an industrially reliable scale. An alternative strategy for implementing NTs or NWs in real-world devices is the use of NT- or NW-network-based structures containing a number of NTs or NWs. Herein, we review the recent progress in NT/NW-network-based integrated devices. The technology for NW/NT-network-based devices is supported by massive integration methods, such as directed assembly, printing and directed growth, and devices based on NW/NT networks display several unique properties, such as percolating conduction and scaling behaviors, that differentiate them from individual NT/NW-based devices. A variety of applications are possible for NT/NW networks, including transistors and sensors, all of which offer unique characteristics for use in integrated nanoelectronics

Transportation of Nanoscale Cargoes by Myosin Propelled Actin Filaments

<p>Myosin II propelled actin filaments move ten times faster than kinesin driven microtubules and are thus attractive candidates as cargo-transporting shuttles in motor driven lab-on-a-chip devices. In addition, actomyosin-based transportation of nanoparticles is useful in various fundamental studies. However, it is poorly understood how actomyosin function is affected by different number of nanoscale cargoes, by cargo size, and by the mode of cargo-attachment to the actin filament. This is studied here using biotin/fluorophores, streptavidin, streptavidin-coated quantum dots, and liposomes as model cargoes attached to monomers along the actin filaments ("side-attached") or to the trailing filament end via the plus end capping protein CapZ. Long-distance transportation (> 100 mu m) could be seen for all cargoes independently of attachment mode but the fraction of motile filaments decreased with increasing number of side-attached cargoes, a reduction that occurred within a range of 10-50 streptavidin molecules, 1-10 quantum dots or with just 1 liposome. However, as observed by monitoring these motile filaments with the attached cargo, the velocity was little affected. This also applied for end-attached cargoes where the attachment was mediated by CapZ. The results with side-attached cargoes argue against certain models for chemomechanical energy transduction in actomyosin and give important insights of relevance for effective exploitation of actomyosin-based cargo-transportation in molecular diagnostics and other nanotechnological applications. The attachment of quantum dots via CapZ, without appreciable modulation of actomyosin function, is useful in fundamental studies as exemplified here by tracking with nanometer accuracy.</p>