Marker-free on-the-fly fabrication of graphene devices based on fluorescence quenching.

Graphene has been dominating the electronic research community recently, with a brisk surge in proposals for its use in novel devices. The aspirations of 2D-carbon-based electronics largely rely on the availability of a mass-production technique to obtain wafer-scale graphene circuits. In this paper, we take a first step towards fulfilling this aspiration by demonstrating a rapid prototyping route for graphene-based devices. The method is based on our observation that graphene quenches the fluorescence from dyes. Utilizing this property, we use a confocal microscope to identify graphene flakes and perform the required lithography steps, bypassing the need for markers and other infrastructure such as atomic force microscopy or e-beam lithography. The versatility of this technique enables it to harbour ambitions of an automated process for large scale in situ assembly of graphene-based circuits.

Effect of stacking order on the electric-field induced carrier modulation in graphene bilayers.

When planar graphene sheets are stacked on top of each other, the electronic structure of the system varies with the position of the subsequent sublattice atoms. Here, we employ scanning photocurrent microscopy to study the disparity in the behavior of charge carriers for two different stacking configurations. It has been found that deviation from the regular Bernal stacking decouples the sheets from each other, which imparts effective electrostatic screening of the farther layer from the underlying backgate. Electrochemical top-gating is demonstrated as a means to selectively tune the charge carrier density in the decoupled upper layer.

Manufacturing nanosized fenofibrate by salt assisted milling.

PURPOSE: The aim of this study is to develop a new process for manufacturing a nano-sized form of the popular cholesterol-reducing drug fenofibrate which can be implemented on industrial scale with minimal changes of currently used production schemes. METHODS: Salt-assisted milling was used to reduce particle size of commercial fenofibrate from micron-sized particles to nanometer domains. RESULTS: The optimal parameters for the salt milling are reported, allowing one to reduce the particle size from tens of micrometers to a hundred of nanometers. Dissolution of nano-sized fenofibrate was studied in various formulations and compared against the micron-sized commercially available fenofibrate. CONCLUSIONS: The nano-sized fenofibrate demonstrates faster dissolution kinetics in aqueous media, simulating stomach environment, within the first 60 min as compared to the micronized form. The highest dissolution rate is achieved with the nano-sized fenofibrate when surfactants, such as sodium dodecyl sulfate or inclusion complex forming agents such as alpha-cyclodextrin, are used.