Gold-carbonaceous materials based heterostructures for gas sensing applications

The carbon nanostructures such as carbon nanotubes and graphene decorated with gold nanoparticles exhibit promising gas sensing applications with enhanced sensitivity.

A high precision length-based carbon nanotube ladder

Today, carbon nanotubes manufacturers as well as users such as molecular electronics, nanomedicine, nano-biotechnology and similar industries are facing a major challenge: lack of length uniformity of carbon nanotubes in mass production. An effective solution to this major issue is the use of a length-based ladder. We are, for the first time, presenting such a valuable tool to determine the length purity. Our length-based carbon nanotubes ladder, containing a series of carbon nanotubes markers with different lengths, is made based on three combined techniques - bio-conjugation, sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), and silver staining. Creating an indicator using conjugation of a biomolecule with carbon nanotubes to make a carbon nanotubes ladder is a novel idea and a significant step forward for length-based carbon nanotubes separation. The very sensitive silver staining technique allows a precise visualization and quantification of the gel. This ladder with a pending patent by Northeastern University is an effective quality control tool when bulk quantities of nanotubes with a desirable length are manufactured.

Nanocomposites based on tubular and onion nanostructures of molybdenum and tungsten disulfides: inorganic design, functional properties and applications

The review concerns the development and the state-of-the-art in studies on the surface modification methods aimed at fabricating promising nanocomposites based on multilayer inorganic tubular and onion (fullerene-like) MoS2 and WS2 nanostructures. The synthetic details and structural features of these materials are considered. Considerable attention is paid to targeted functionalization of molybdenum and tungsten disulfide nanostructures and to fundamental principles that underlie their ability to chemical interactions. The functional properties and applications of the obtained materials are described.

The bibliography includes 183 references.

Osteoblast function on electrically conductive electrospun PLA/MWCNTs nanofibers

The electrospinning process was utilized successfully to fabricate the random oriented and aligned electrically conductive nanofibers of biodegradable poly-DL-lactide (PLA) in which multiwalled carbon nanotubes (MWCNTs) were embedded. The topographical features of the composite nanofibers were characterized by SEM. The dispersion and alignment of MWCNTs in nanofiber matrix were observed by TEM. The in vitro degradation was characterized in terms of the morphological change, the mass loss and the reduction of polymer molecular weight as well as the decrease of pH value of degradation media. In particular, these conductive nanofiber meshes offered a unique system to study the synergistic effect of topographic cues and electrical stimulation on osteoblasts outgrowth as a way of exploring their potential application in bone tissue engineering. The results of obsteoblasts assay unstimulated showed that the aligned nanofibers as topographic cues could enhance the extension and direct the outgrowth of obsteoblasts better than random fibers. In the presence of direct current (DC) of 100 μA, the obsteoblasts on all samples grew along the electrical current direction. The cellular elongation and proliferation were mainly dependent on the electrical stimulation whereas the topographical features played a minor role in them. Therefore, electrical stimulation with an appropriate DC value imparted on conductive substrate had great potential in application of bone tissue engineering.