Abstract: Methods for building sensor arrays using electrical signals to selectively functionalize individual electrodes in an array of electrically addressable electrodes are provided. These methods are useful for providing sensor arrays for use in chemical and biochemical assays. The method is based on the sequential electrochemical reduction of functional groups on individual electrodes in order to selectively promote the functionalization of selected electrodes with selected binding entities.

Abstract: Disclosed are supercapacitors having organosilicon electrolytes, high surface area/porous electrodes, and optionally organosilicon separators. Electrodes are formed from high surface area material (such as porous carbon nanotubes or carbon nanofibers), which has been impregnated with the electrolyte. These type devices appear particularly suitable for use in electric and hybrid electric vehicles.

Abstract: Radio-frequency (RF) excitation is used for direct detection of hybridization events at microelectrodes with surface-attached DNA oligomers. A homodyne reflectometer operates on a high frequency carrier to detect the presence of a low-frequency modulation signal. Without non-linearities in an interface, the modulation signal is not impressed upon the carrier signal. As such, the reflectometer can sensitively measure changes in dielectric properties without interference from other sources of capacitance/resistance unrelated to the reaction at the surface.

Abstract: This invention provides surfaces having nanocylinders, such as carbon nanotubes, attached thereto through biomolecular interactions, devices made from assemblies of nanocylinder-modified surfaces, and methods for producing nanocylinder modified surfaces. A variety of biomolecular interactions may be used to attach the nanocylinders to the surfaces, including hybridization of complementary oligonucleotide sequences and receptor-ligand interactions.

Abstract: A method for converting arsenite in a source to arsenate is disclosed. The method involves incubating bacteria of a Thermus species in the source at a temperature at which the bacteria can convert at least some of the arsenite to arsenate.

Abstract: Radio-frequency (RF) excitation is used for direct detection of hybridization events at microelectrodes with surface-attached DNA oligomers. A homodyne reflectometer operates on a high frequency carrier to detect the presence of a low-frequency modulation signal. Without non-linearities in an interface, the modulation signal is not impressed upon the carrier signal. As such, the reflectometer can sensitively measure changes in dielectric properties without interference from other sources of capacitance/resistance unrelated to the reaction at the surface.

Abstract: A method for converting arsenite in a source to arsenate is disclosed. The method involves incubating bacteria of a Thermus species in the source at a temperature at which the bacteria can convert at least some of the arsenite to arsenate.

Abstract: Chemically-modified surfaces on unoxidized, bromine- or iodine-terminated carbon, silicon, and germanium substrates are disclosed. Visible light mediates the reaction of protected &ohgr;-modified, &agr;-unsaturated aminoalkenes (preferred) with bromine- or iodine-terminated carbon, silicon, or germanium surfaces. Removal of the protecting group yields an aminoalkane-modified silicon surface. These amino groups can be coupled to terminal-modified oligonucleotides using a bifunctional crosslinker, thereby permitting the preparation of modified surfaces and arrays. Methods for controlling the surface density of molecules attached to the substrate are also disclosed.

Abstract: Chemically-modified surfaces on unoxidized carbon, silicon, and germanium substrates are disclosed. Ultraviolet radiation mediates the reaction of protected &ohgr;-modified, &agr;-unsaturated aminoalkenes (preferred) with hydrogen-terminated carbon, silicon, or germanium surfaces. Removal of the protecting group yields an aminoalkane-modified silicon surface These amino groups can be coupled to terminal-modified oligonucleotides using a bifunctional crosslinker, thereby permitting the preparation of modified surfaces and arrays. Methods for controlling the surface density of molecules attached to the substrate are also disclosed.

Abstract: Chemically-modified surfaces on unoxidized carbon, silicon, and germanium substrates are disclosed. Ultraviolet radiation mediates the reaction of protected &ohgr;-modified, &agr;-unsaturated aminoalkenes (preferred) with hydrogen-terminated carbon, silicon, or germanium surfaces. Removal of the protecting group yields an aminoalkane-modified silicon surface. These amino groups can be coupled to terminal-modified oligonucleotides using a bifunctional crosslinker, thereby permitting the preparation of modified surfaces and arrays. Methods for controlling the surface density of molecules attached to the substrate are also disclosed.

Abstract: Chemically-modified surfaces on unoxidized, bromine- or iodine-terminated carbon, silicon, and germanium substrates are disclosed. Visible light mediates the reaction of protected &ohgr;-modified, &agr;-unsaturated aminoalkenes (preferred) with bromine- or iodine-terminated carbon, silicon, or germanium surfaces. Removal of the protecting group yields an aminoalkane-modified silicon surface. These amino groups can be coupled to terminal-modified oligonucleotides using a bifunctional crosslinker, thereby permitting the preparation of modified surfaces and arrays. Methods for controlling the surface density of molecules attached to the substrate are also disclosed.

Abstract: Systems and methods for fabricating ordered anisotropic organic monolayers are described. An apparatus includes a substrate including a surface; and an ordered organic monolayer chemically bonded to the surface, the ordered organic monolayer including a plurality of cyclic organic molecules, each of the plurality of cyclic organic molecules being obtained from an unsaturated cyclic organic reactant that is chemically bonded to the surface through an addition reaction. The systems and methods provide advantages in that translational and rotational order from the substrate is extended into the monolayer.

Abstract: A controller for an inchworm type linear transducer is constructed so as to be extremely low noise and to permit very fine positioning. This is done by storing the desired output waveforms in digital form in an EEPROM memory array and then counting through the address locations of the memory array to re-create the desired waveform. An analog amplifier is used to actually drive the piezoelectric elements in the transducer.