Abstract: Methods for covalently modifying surfaces of various substrates are disclosed, along with various substrates having surfaces modified by such methods. Candidate surfaces include various polymeric, siliceous, metallic, allotrophic forms of carbon, and semiconductor surfaces. The surfaces are exposed to a reagent, having molecules each comprising a nitrenogenic group and a functionalizing group, in the presence of energized charged particles such as electrons and ions, photons, or heat, which transform the nitrenogenic reagent to a nitrene intermediate. The nitrene covalently reacts with any of various chemical groups present on the substrate surface, thereby effecting nitrene addition of the functionalizing groups to the substrate surface. The functionalizing groups can then participate in downstream chemistry whereby any of a large variety of functional groups, including biological molecules, can be covalently bonded to the surface, thereby dramatically altering the chemical behavior of the surface.

Abstract: Dendritic derivatives of 3,5-bis(aminomethyl)benzene and aminomethyl benzene core groups are disclosed. In each derivative, termed an "amplifier" because the dendritic structure on each molecule terminates with multiple termini to each of which an "active group" can be attached, the desired effect of the active group per mole is amplified compared to conventional compounds having only one active group per molecule. Amplifier molecules can include a targeting group permitting the molecules to preferentially attach to a particular anatomical or physiological situs. Active groups are any of various pharmacologically or therapeutically active moieties, including moieties useful for magnetic-resonance contrast enhancement. The dendritic structures comprise linkers and branch groups covalently bonded to each other in any of various structural combinations. The amplifiers can be prepared as a solution or mixture with a physiologically compatible carrier for administration to a warm-blooded animal subject.

Abstract: Methods and reaction systems are disclosed that are adapted for forming crystallites having novel crystal habits and/or morphologies compared to conventional crystallites of the same chemical composition. The methods and reaction systems involve chemical reactions between at least two reactant compounds occurring in a liquid (or gel) that form insoluble crystallite products. At least one of the reactants is rendered soluble in a solvent in which the reactant is not normally soluble by adding an agent that forms soluble molecular complexes of the agent and the reactant. The complexing agent not only facilitates dissolution of the reactant in the solvent but also plays a role in how the faces of crystals comprising the crystallite product are enlarged during formation of the product. Products having such altered crystallite structure have a number of possible uses.

Abstract: Chemical and biosensors are disclosed. An optical waveguide is used to conduct electromagnetic radiation by total internal reflection in parallel through a reference waveguide portion and at least one analyte waveguide portion. The electromagnetic radiation is then converged into an exit beam. The external surface of at least the analyte portion is covalently modified, or functionalized, relative to the reference portion. Resulting interaction of the functionalized surface with molecules comprising an analyte causes a phase change in the electromagnetic radiation passing through the analyte portion relative to the reference portion sufficient to generate a corresponding and measurable interference pattern in the exit beam.

Abstract: Disclosed are amplifier molecules: various organic compounds having branched structures terminating with amine groups to which pharmacologically active groups can be chemically attached. A number of MRI contrast-enhancing agents were synthesized, each comprising plural active groups, such as stable nitroxides and complexes of trivalent metal cations. Such syntheses were successfully performed using a number of amplifiers having different branched structures, demonstrating the general utility of the pertinent chemistry in the synthesis of amplifiers having any of a wide variety of pharmacologically active groups. Amplifiers were also synthesized having linkers terminating with chemically reactive groups such as isothiocyanates, which render the amplifier bifunctional: attachable to polymers, biomacromolecules, or other biocompatible entity possessing multiple reactive sites such as terminal amines.

Abstract: Data storage methods and apparatus are disclosed that utilize a swept-carrier optical approach with an inhomogeneously broadened absorber material having multiple special storage cells. Data are encoded on a data pulse by appropriately modulating the data pulse. Data storage in a storage cell is effected by exposing the cell to the data pulse and a reference pulse cotemporal with the data pulse. Both the data and reference pulses are frequency-chirped across the inhomogeneously broadened bandwidth of the absorber material, the data pulse being chirped at a frequency that is offset relative to the reference pulse. Data retrieval from the storage cell is performed by exposing the cell to a read pulse which causes the cell to produce a signal pulse comprising the encoded data. The read pulse can have a temporal profile that produces a signal pulse shaped either similarly to the data pulse or as a mirror image of the data pulse.

Abstract: Disclosed are amplifier molecules: various organic compounds having branched structures terminating with amine groups to which pharmacologically active groups can be chemically attached. A number of MRI contrast-enhancing agents were synthesized, each comprising plural active groups, such as stable nitroxides and complexes of trivalent metal cations. Such syntheses were successfully performed using a number of amplifiers having different branched structures, demonstrating the general utility of the pertinent chemistry in the synthesis of amplifiers having any of a wide variety of pharmacologically active groups. Amplifiers were also synthesized having linkers terminating with chemically reactive groups such as isothiocyanates, which render the amplifier bifunctional: attachable to polymers, biomacromolecules, or other biocompatible entity possessing multiple reactive sites such as terminal amines.

Abstract: Methods for synthesizing solid-state crystalline alloys and products made therefrom are disclosed. Plural repeat units, each comprising an ordered sequence of superposed layers of preselected solid-state reactants, are formed superposedly on a surface of a solid substrate to form a modulated composite of the reactants. The layers comprising a repeat unit are controllably formed to have relative thicknesses corresponding to the stoichiometry of a preselected solid compound found on a phase diagram of the reactants. Each repeat unit also has a repeat-unit thickness no greater than a critical thickness for a diffusion couple of the reactants, where the repeat-unit thickness is preferably less than or equal to about 100 .ANG.. The modulated composite is then heated to an interdiffusion temperature lower than a nucleation temperature for the reactants for a time sufficient to form an amorphous alloy of the reactants having a stoichiometry corresponding to the preselected solid compound.

Abstract: Disclosed are amplifier molecules: various organic compounds having branched structures terminating with amine groups to which pharmacologically active groups can be chemically attached. A number of MRI contrast-enhancing agents were synthesized, each comprising plural active groups, such as stable nitroxides and complexes of trivalent metal cations. Such syntheses were successfully performed using a number of amplifiers having different branched structures, demonstrating the general utility of the pertinent chemistry in the synthesis of amplifiers having any of a wide variety of pharmacologically active groups. Amplifiers were also synthesized having linkers terminating with chemically reactive groups such as isothiocyanates, which render the amplifier bifunctional: attachable to polymers, biomacromolecules, or other biocompatible entity possessing multiple reactive sites such as terminal amines.

Abstract: Polymers having photoreactive metal-metal bonds along the backbone of the polymer are disclosed, which bonds rendering the polymers photo-labile. Metals participating in such metal-metal bonds are from Groups VIB and VIIB (first column) of the Periodic Table as well as nickel. Each metal-metal bond is present in a cord group present in at least one monomer incorporated into the polymer. The core group also comprises carbonyl groups and an aromatic cyclopentadienyl (Cp) group bonded to each metal atom. Various organic and organosiloxane linker groups bonded to the Cp groups render the core group-containing monomer polymerizable into a composition of matter having physical properties determined in part by the chemical composition and conformation of the linkers. Reactions for synthesizing core groups, monomers, and various polymers therefrom are disclosed, including copolymerization reactions.

Abstract: A method and probes are disclosed for the localization of functional receptors by electron microscopy (EM). Electron dense probes are directed to receptors by means of specific ligand-receptor interactions and subsequently anchored covalently to target cellular material. A particular probe is a complex between colloidal gold and dextran derivatized with diaminohexane and containing photo-activatable nitroarylazido groups. Ligands with a specific affinity for certain receptors can be covalently attached to the complex to provide receptor-specific markers. For example, ouabain can be covalently attached to the dextran matrix to produce a probe specific for functional units of Na,K-ATPase. Covalent attachment of the bound probes at or near their respective receptors greatly enhances retention of probe during washing and standard procedures of fixation and dehydration in preparation for EM.

Abstract: Nitroxide contrast agents for MRI have a long useful life and can be administered in low concentration doses. Such agents include nitroxide-doped liposomes that encapsulate an oxidant and large molecules having surfaces covered with persistent nitroxide free radicals.

Abstract: Micropole undulators for use in the generation of x-rays from moving charged particles and methods for manufacturing such undulators are disclosed.One type of micropole undulator has two jaws containing rows of spaced apart poles arranged so that each pole produces a magnetic field aligned with all other similar fields. An external biasing field extends through the jaws so that an overall undulator field of substantially sinusoidal shape and substantially zero average value extends along the undulator axis. Preferably, the poles are bars formed of a magnetizable, but unmagnetized, material so that, after the jaws are assembled, all of the bars can be magnetized simultaneously in a uniform magnetic field of suitable strength.