Abstract: The present invention provides methods of on-demand, reversible generation of aqueous two-phase microdroplets core-shell microbeads, microparticle preparations comprising the core-shell microbeads, and drug delivery formulation comprising the microparticle preparations. Because these aqueous microdroplets have volumes comparable to those of cells, they provide an approach to mimicking the dynamic microcompartmentation of biomaterial that naturally occurs within the cytoplasm of cells. Hence, the present methods generate femtoliter aqueous two-phase droplets within a microfluidic oil channel using gated pressure pulses to generate individual, stationary two-phase microdroplets with a well-defined time zero for carrying out controlled and sequential phase transformations over time. Reversible phase transitions between single-phase, two-phase, and core-shell microbead states are obtained via evaporation-induced dehydration and water rehydration.

Abstract: The present invention provides methods of on-demand, reversible generation of aqueous two-phase microdroplets core-shell microbeads, microparticle preparations comprising the core-shell microbeads, and drug delivery formulation comprising the microparticle preparations. Because these aqueous microdroplets have volumes comparable to those of cells, they provide an approach to mimicking the dynamic microcompartmentation of biomaterial that naturally occurs within the cytoplasm of cells. Hence, the present methods generate femtoliter aqueous two-phase droplets within a microfluidic oil channel using gated pressure pulses to generate individual, stationary two-phase microdroplets with a well-defined time zero for carrying out controlled and sequential phase transformations over time. Reversible phase transitions between single-phase, two-phase, and core-shell microbead states are obtained via evaporation-induced dehydration and water rehydration.

Abstract: A microfluidic device for generation of monodisperse droplets and initiating a chemical reaction is provided. The microfluidic device includes a first input microchannel having a first dimension and including a first phase located therein. The device also includes a second input microchannel having a second dimension and including a second phase located therein. In accordance with the present disclosure, the second dimension is different from the first dimension and the first phase is immiscible in the second phase. A microchannel junction is also present and is in communication with the first input microchannel and the second input microchannel. The device further includes an output channel in communication with the microchannel junction and set to receive a monodisperse droplet. In the present disclosure, the difference in the first dimension and the second dimension creates an interfacial tension induced force at the microchannel junction which forms the monodisperse droplet.

Abstract: The invention is a device including array of aciive regions for use in reacting one or more species in at least two of the active regions in a sequential process, e.g., sequential reactions. The device has a transparent substrate member, which has a surface region and a silane material overlying the surface region. A first active region overlies a first portion of the silane material. The first region has a first dimension of less than 1 micron in size and has first molecules capable of binding to the first portion of the silane material. A second active region overlies a second portion of the silane material. The second region has a second dimension of less than 1 micron in size, second molecules capable of binding to the second portion of the active region, and a spatial distance separates the first active region and the second active region.

Abstract: A microfluidic device for generation of monodisperse droplets and initiating a chemical reaction is provided. The microfluidic device includes a first input microchannel having a first dimension and including a first phase located therein. The device also includes a second input microchannel having a second dimension and including a second phase located therein. In accordance with the present disclosure, the second dimension is different from the first dimension and the first phase is immiscible in the second phase. A microchannel junction is also present and is in communication with the first input microchannel and the second input microchannel. The device further includes an output channel in communication with the microchannel junction and set to receive a monodisperse droplet. In the present disclosure, the difference in the first dimension and the second dimension creates an interfacial tension induced force at the microchannel junction which forms the monodisperse droplet.

Abstract: A metal-filled nanostructure and fabrication methods thereof are discussed. A metal-filled nanostructure according to an embodiment of the present invention comprises a metal filling and a nanostructure shell, and may provide superior conductivity and contact resistance over those inherent in the nanostructure shell. In a preferred embodiment, the metal filled nanostructure comprises a continuous metal nanowire inserted into a single-walled carbon nanotube using an electrowetting technique.

Abstract: Embodiments in accordance with the present invention relate to techniques for the growth and attachment of single wall carbon nanotubes (SWNT), facilitating their use as robust and well-characterized tools for AFM imaging and other applications. In accordance with one embodiment, SWNTs attached to an AFM tip can function as a structural scaffold for nanoscale device fabrication on a scanning probe. Such a probe can trigger, with nanometer precision, specific biochemical reactions or conformational changes in biological systems. The consequences of such triggering can be observed in real time by single-molecule fluorescence, electrical, and/or AFM sensing. Specific embodiments in accordance with the present invention utilize sensing and manipulation of individual molecules with carbon nanotubes, coupled with single-molecule fluorescence imaging, to allow observation of spectroscopic signals in response to mechanically induced molecular changes.

Abstract: Probe tips comprising tips and coatings are described. The tips and coatings may be selected to provide various probe-tip features, including, but not limited to, high reproducibility, high reliability, low cost, ultra-sharpness, high conductivity and/or simultaneous critical dimension imaging and sidewall roughness analysis.

Abstract: A method for fabricating assembled structures. The method includes providing a tip structure, which has a first end, a second end, and a length defined between the first end and the second end. The second end is a free end. The method includes attaching a nano-sized structure along a portion of the length of the tip structure to extend a total length of the tip structure to include the length of the tip structure and a first length associated with the nano-sized structure. The method includes shortening the nano-sized structure from the first length to a second length. The method also includes pushing the nano-sized structure in a direction parallel to the second length to reduce the second length to a third length of the nano-sized structure along the direction parallel to the second length to cause the nano-sized structure to move along a portion of the length of the tip structure.

Abstract: Volatile and non-volatile solid state molecular switching devices which are electrically addressable and may be used in memory cells, routing circuits, inverters and field programmable devices which may or may not be designed to exhibit diode behavior. The molecular switching devices include certain [2] catenanes as bistable molecules which are sandwiched between two switch terminals. The switches are extremely small and have dimensions which range from several microns down to a few nanometers.