Abstract: Methods for preparing uniformly sized micropanicles, with an optional polymeric coating generally include: 1) providing nanoparticles, preferably having a size of between 1 nm and 100 nm; 2) adding a hydrophobic surface layer to the nanoparticles; 3) making a suspension of the hydrophobic nanoparticles and a polymerization initiator in an hydrophobic solvent; 4) dissolving a monomer in the hydrophobic solvent; 5) making an emulsion by dispersing droplets of the hydrophobic solvent in a continuous aqueous phase with an emulsifier; 6) sizing the first emulsion to provide a second emulsion of the same components in which the droplets are substantially uniform and between 2 and 20 um in size; 7) evaporating at least a substantial portion of the dispersed hydrophobic droplets to assemble nanoparticles to form micropanicles suspended now in the aqueous phase; 8) replacing the first surfactant with a second surfactant, which is preferably a polymerizable surfactant; 9) adding a polymerizable monomer to the aqueous p

Abstract: A method of separating a target biological analyte from a mixture of substances in a fluid sample employs nonlinear magnetophoresis. Magnetic particles having the capacity to bind to the target analyte are contacted with the fluid sample so that the analyte is immobilized on the surface of at least some of the particles. The magnetic particles are provided adjacent an array of micromagnets patterned on a substrate so that the particles are attracted the micromagnets. The magnetic particles are then subjected to a traveling magnetic field operating at or above a frequency effective to sweep those particles not bound to analyte to an adjacent micromagnet. Those magnetic particles bound to analyte have a larger size or smaller magnetic moment that prevents them from being moved to adjacent micromagnets, thereby affording separation of the analyte.

Abstract: Bioanalytical device that includes a biofunctional component and an optional sensor component. The device includes arrays of addressable, durable, asymmetric biofunctional membranes containing protein transducers capable of unidirectional transport of analytes. Suitable protein transducers include members of the ATP-binding cassette family, such as P-glycoprotein.

Abstract: A sensor for a selected analyte in a test sample has (a) a semipermeable membrane with pores for retaining the analyte, where the membrane has been chemically modified by attachment of membrane modifiers; (b) immunoassay labels which have label binding ligands where these label binding ligands will have a binding affinity for the membrane modifiers in the presence of the analyte, and a measurably different binding affinity for the membrane modifiers in the absence of the analyte; and (c) a label detecting system, for detecting the presence of the labels on the membrane.

Abstract: A sensor for a selected analyte in a test sample has (a) a semipermeable membrane with pores for retaining the analyte, where the membrane has been chemically modified by attachment of membrane modifiers; (b) immunoassay labels which have label binding ligands where these label binding ligands will have a binding affinity for the membrane modifiers in the presence of the analyte, and a measurably different binding affinity for the membrane modifiers in the absence of the analyte; and (c) a label detecting system, for detecting the presence of the labels on the membrane.

Abstract: A process and apparatus for the collection of biological materials from air. Collection and separation devices utilize a novel membrane structure formed from a functionalized inorganic mesoporous membrane supported by porous substrate.

Abstract: An ultrasonic energy source is used to provide a variable force for measuring the binding forces between molecular entities and for sensing the presence of an analyte in a test sample. The device includes a surface that has a first binding member attached thereto and one or more particles that have a second binding member attached thereto. A reaction vessel is provided for exposing the surface to the particles whereby, if the first binding member has a binding affinity for the second binding member, a complex is formed between individual first binding members and individual second binding members and the particles thereby become immobilized with respect to the surface. The ultrasonic energy source is positioned for applying a variable ultrasonic force onto the surface, and the position of the particles is monitored as the intensity of the ultrasonic force is varied.

Abstract: A sensor for a selected analyte in a test sample has (a) a semipermeable membrane with pores for retaining the analyte, where the membrane has been chemically modified by attachment of membrane modifiers; (b) immunoassay labels which have label binding ligands where these label binding ligands will have a binding affinity for the membrane modifiers in the presence of the analyte, and a measurably different binding affinity for the membrane modifiers in the absence of the analyte; and (c) a label detecting system, for detecting the presence of the labels on the membrane.

Abstract: Biological material in a sample is reacted with a novel functionalized superparamagnetic Fe/Au nanoparticle that specifically binds to the biological material to produce a magnetic particle/biological material complex. The biological material is detected upon application of an electromagnetic magnetic field which separates the magnetic bound complex from other components of the reaction mixture.

Abstract: A sensor for a selected analyte in a test sample has (a) a semipermeable membrane with pores for retaining the analyte, where the membrane has been chemically modified by attachment of membrane modifiers; (b) immunoassay labels which have label binding ligands where these label binding ligands will have a binding affinity for the membrane modifiers in the presence of the analyte, and a measurably different binding affinity for the membrane modifiers in the absence of the analyte; and (c) a label detecting system, for detecting the presence of the labels on the membrane.

Abstract: A process and apparatus for the collection of biological materials from air. Collection and separation devices utilize a novel membrane structure formed from a functionalized inorganic mesoporous membrane supported by porous substrate.

Abstract: An ultrasonic energy source is used to provide a variable force for measuring the binding forces between molecular entities and for sensing the presence of an analyte in a test sample. The device includes a surface that has a first binding member attached thereto and one or more particles that have a second binding member attached thereto. A reaction vessel is provided for exposing the surface to the particles whereby, if the first binding member has a binding affinity for the second binding member, a complex is formed between individual first binding members and individual second binding members and the particles thereby become immobilized with respect to the surface. The ultrasonic energy source is positioned for applying a variable ultrasonic force onto the surface, and the position of the particles is monitored as the intensity of the ultrasonic force is varied.

Abstract: An ultrasonic energy source is used to provide a variable force for measuring the binding forces between molecular entities and for sensing the presence of an analyte in a test sample. The device includes a surface that has a first binding member attached thereto and one or more particles that have a second binding member attached thereto. A reaction vessel is provided for exposing the surface to the particles whereby, if the first binding member has a binding affinity for the second binding member, a complex is formed between individual first binding members and individual second binding members and the particles thereby become immobilized with respect to the surface. The ultrasonic energy source is positioned for applying a variable ultrasonic force onto the surface, and the position of the particles is monitored as the intensity of the ultrasonic force is varied.

Abstract: A sensor for a selected target species has (a) a substrate which has been chemically modified by attachment of substrate modifiers; (b) one or more magnetically active beads which have been chemically modified by attachment of bead modifiers, where these bead modifiers will have a binding affinity for the substrate modifiers in the presence of the target species, and a measurably different binding affinity for the substrate modifiers in the absence of the target species; (c) an adjustable source of a magnetic field for exerting a force on the beads; and (d) an imaging system, for observing and counting beads bound to the substrate. In a preferred embodiment, the invention further has a system for identifying clusters of beads, and for removing the effect of such clusters from measurements of the target analyte. As with other assays, the sensor relies on the ability of certain molecules to bind with specific target (analyte) molecules.

Abstract: An ultrasonic energy source is used to provide a variable force for measuring the binding forces between molecular entities and for sensing the presence of an analyte in a test sample. The device includes a surface that has a first binding member attached thereto and one or more particles that have a second binding member attached thereto. A reaction vessel is provided for exposing the surface to the particles whereby, if the first binding member has a binding affinity for the second binding member, a complex is formed between individual first binding members and individual second binding members and the particles thereby become immobilized with respect to the surface. The ultrasonic energy source is positioned for applying a variable ultrasonic force onto the surface, and the position of the particles is monitored as the intensity of the ultrasonic force is varied.

Abstract: A sample support member for atomic force microscopy of intermolecular interactions includes a sample support base having a plurality of protrusions, each protrusion having an apical substrate region or tip that has been chemically modified by the immobilization thereon of a sample compound or of a linking compound that is capable of binding a sample compound. A reference compound support member has a surface region having at least one reference compound immobilized thereon.The relative position and orientation of the reference compound support member and the substrate support member are controlled to select a particular protrusion and to cause an interaction between a reference compound immobilized on the surface region of the free end of the cantilever and the sample compound immobilized on the apical substrate area of the selected protrusion. A physical parameter associated with the interaction between the reference compound and the sample compound can be measured.

Abstract: A method is disclosed for measuring intramolecular forces within a sample compound by providing an atomic force microscope that includes a sample support member and a cantilever. The sample support member has a plurality of protrusions, and each protrusion has an apical substrate region that has been chemically modified to have a sample compound immobilized thereon. The cantilever has a fixed end and a free end, the free end having a surface region that has been chemically modified to have a grasping compound immobilized thereon. To measure intramolecular forces within the sample compound, the relative position and orientation of the cantilever and the sample support member are controlled to select a particular protrusion and to allow a molecule of the grasping compound to bind with a molecule of the sample compound.

Abstract: The present invention is a method and apparatus for detecting a target species. The target molecule may be in liquid phase (in solution) or (for some embodiments of the invention) in vapor phase. A sensor according to the present invention monitors whether a target species has selectively bound to groups on the cantilever surface by monitoring the displacement of the cantilever, and hence the force acting on the cantilever. This force acting on the cantilever arises from the force acting on a structure that moves in electric or magnetic field, and that may be selectively bound to the cantilever. In the case of target species having a sufficiently large net electric charge or dipole moment, the target species itself may serve as the structure that moves in an electric field.