Abstract: The present invention is directed to tube-in-a-tube electronic materials and electronic chemical sensors comprising tube-in-a-tube configurations such as covalently functionalized double-walled carbon nanotubes.

Abstract: The present invention is directed to tube-in-a-tube electronic materials and electronic chemical sensors comprising tube-in-a-tube configurations such as covalently functionalized double-walled carbon nanotubes.

Abstract: One embodiment of the invention relates to a microfluidic apparatus for controlling fluid flow velocity during electroosmotic flow. According to one aspect of the invention, a voltage applied to a gate electrode modulates flow velocity within an associated microchannel, where the gate voltage is separate from any voltage used to induce electroosmotic flow. According to another aspect of the invention, the flow control apparatus combines multiple gate electrodes to control flow in a microfluidic network. According to one embodiment of the invention, the flow control apparatus is fabricated in a planar silicon substrate. According to another embodiment of the invention, the flow control apparatus is fabricated using polymer materials.

Abstract: Oligosaccharides are structurally characterized utilizing enzymatic digestion with an array of highly specific exoglycosidases followed by electrochemical detection and measurement of the molar quantity of cleaved monosaccharides in each enzymatic digest.

Abstract: The complexing of an antibody-antigen binding pair is determined by observing the change in fluorescence of a pH-sensitive fluorochrome attached to one of the members of the binding pair. When the binding is conducted in a solution having a pH other than the isoelectric point of the antibody, there will be a change in the pH of the microenviromnent surrounding the fluorochrome. This change will correspond to a change in the observed fluorescent intensity. Either member of the binding pair can be labeled, and combined with that member whose presence is suspect, in an immunoassay.

Abstract: Capillary zone electrophoresis is enhanced by the application of an electric field across the interior of the capillary tube. This external electric field is applied through a conductive member at the exterior of the capillary tube. The external field vectorially couples with the internal field, controlling the polarity and the magnitude of the surface (zeta) potential on the interior surface of the capillary. The control of the surface (zeta) potential reduces adsorption of macromolecular onto the interior surface of the capillary tube, by inducing electrostatic repulsions between the macromolecules, and the capillary surface. Additionally, the control of the surface (zeta) potential can retard, and even reverse, electroosmotic flow, depending upon the magnitude of those fields.