Abstract: A method of individually analyzing with a surface acoustic wave (SAW) sensor apparatus the presence or absence of at least two different target antigens in a liquid sample is described. The method comprises providing and running a single flow cell comprising a SAW sensor chip with at least two, e.g. twelve, SAW sensor elements, each comprising an individual coating immobilizing and exposing a modified antigen that has a weaker affinity for an antibody which is specific for one of the target antigens than the target antigen itself. Such a flow cell and surface acoustic wave (SAW) sensor chip for immunological displacement reactions are also disclosed.

Abstract: A coated metal surface on a solid support, wherein the coating consists of a protein layer firmly attached to the metal surface, and said protein layer is coupled to linker molecules that are bound to low molecular weight antigens, wherein the linker molecules are coupled to the protein layer and are bound to the antigen via functional end groups and contain between the functional end groups an aliphatic hydrocarbon of 1, 2 or 3 carbon atoms, and wherein the antigens are optionally reversibly bound to antibodies specific for the antigens, is described. The coated metal surface on a solid support may be used in a method of detecting analyte antigens as part of an analysis device, such as a Piezoelectric Crystal Microbalance device or a Surface Plasmon Resonance biosensor, for detection in an aqueous solution of an analyte antigen with higher affinity to an antibody than the antigen of the coating by monitoring the displacement of the antibody from the coating.

Abstract: A system, device and method for detection of several individual analytes in a test solution aliquot (83) with an array of individually operated piezoelectric crystal microbalances are described. The system comprises a connecting station (100) that receives a plurality of individually specific piezoelectric crystal microbalance flow-trough cells (10), each containing a piezoelectric crystal (50) carrying electrodes (56,62) and a coating (66,46) exposing a first member of an interaction pair specific for an individual analyte being a second member of the interaction pair. Flowing means (70) flows a solution (75) and the test solution aliquot (83) to and through a cell compartment of each of the cells (10) via the connecting station (100). Power and measurement means (130) oscillate the piezoelectric crystal(s) (50). A change in oscillating characteristics of the crystal(s) (50), following interaction between the first and second members of the interaction pair, detects presence of the individual analyte(s).

Abstract: A continuously repeatable method of detecting possible presence of one or several different selected target antigen(s), such as explosives and/or narcotics, in a predetermined test volume with a flow-through analysis device, such as a Piezoelectric Quartz Crystal Microbalance device (QCM), an Ellipsometer device or a Surface Plasmon Resonance biosensor device, is described. The device is equipped with one or several fluidly connected, individually operated, flow-through testing cells, each cell containing a sensing surface, each sensing surface comprising a selected modified target antigen immobilized thereon, which modified antigen has weaker affinity than the target antigen for a selected antibody specific for the selected target antigen. One testing cell is for analyzing a target antigen by the competition mode, whereas optional other testing cells are individually selected for analysis by the competition mode or the displacement mode.

Abstract: A coated metal surface on a solid support, wherein the coating consists of a self-assembled monolayer (SAM) of oligo(ethylene glycol)-terminated amide group-containing alkyl thiols firmly attached to the metal surface via the thiol-end and low molecular weight antigens bound via an amide-group to the SAM-forming OEG molecule, wherein the alkyl portion has 1-20 methylene groups, wherein the oligo(ethylene glycol) portion has 1-15 ethylene oxy units, and wherein the antigens, such as explosives and narcotics, are optionally reversibly bound to antibodies specific for the antigens, is disclosed. The coated metal surface on a solid support may be used in a method of detecting analyte antigens as part of an analysis device, such as a Piezoelectric Crystal Microbalance device or a Surface Plasmon Resonance biosensor, for detection in an aqueous solution of an analyte antigen with higher affinity to an antibody than the antigen of the coating by monitoring the displacement of the antibody from the coating.

Abstract: A mixture of isolated or synthetic affinity molecules in a liquid carrier is disclosed. The mixture comprises at least two different affinity molecules, each with affinity for a predetermined analyte, for use in a single or multi flow cell piezoelectric crystal micro balance apparatus. Each isolated or synthetic affinity molecule forms together with the predetermined analyte an interaction pair selected from the group consisting of anion-cation, antibody-antigen, receptor-ligand, enzyme-substrate, oligonucleotide-oligonucleotide with complementary sequence, oligonucleotide-protein, oligonucleotide-cell, and peptide nucleic acid (PNA) oligomer-polynucleotide, wherein the polynucleotide may be selected from the group consisting of RNA, DNA and PNA polymers complementary to PNA oligomer. Use of the mixture for introduction into the liquid flow of a single or multi flow cell piezoelectric crystal micro balance apparatus is also described, as well as a kit containing the mixture.

Abstract: A protein comprising an antigen-binding portion formed by two cooperating peptide sequences of FIGS. 3A and 3B of the application. The protein may alternatively comprise an altered antigen-binding portion where at least one of the peptide sequences is an altered sequence, an altered sequence being a sequence of FIG. 3A or 3B in which one or more of an amino acid residue has been added, deleted or replaced by another amino acid residue. The altered antigen-binding portion retains substantially the same antigen-binding specificity as said antigen-binding portion. Also disclosed are apparatus, systems and methods for detecting small assayed molecules in a sample using the protein.

Abstract: An apparatus (10) and a method for concentrating and transferring volatile compounds contained in a sample on a detachable solid support (12) into a liquid for subsequent detection and/or analysis of the volatile compounds, are described. The apparatus comprises a holder (14) for the solid support (12), means (16) for transporting the holder (14) to a heating position on a heatable plate (18), an enclosed space-creating arrangement comprising the heatable plate (18) attached to a movable housing (30), the holder (14), the solid support (12), a funnel (20) on the solid support (12), and inside the funnel (20) a chilled member (22), means inside the housing (30) for heating the heatable plate (18) to evaporate the volatile compounds which then are condensed on the chilled member (22), means (24) for transporting the chilled member (22) from a cooler (26) to the inside of the funnel (20) and from there to a position (28) where condensed compounds are removed from the chilled member (22) into a liquid.

Abstract: A system, device and method for detection of several individual analytes in a test solution aliquot (83) with an array of individually operated piezoelectric crystal microbalances are described. The system comprises a connecting station (100) that receives a plurality of individually specific piezoelectric crystal microbalance flow-trough cells (10), each containing a piezoelectric crystal (50) carrying electrodes (56,62) and a coating (66,46) exposing a first member of an interaction pair specific for an individual analyte being a second member of the interaction pair. Flowing means (70) flows a solution (75) and the test solution aliquot (83) to and through a cell compartment of each of the cells (10) via the connecting station (100). Power and measurement means (130) oscillate the piezoelectric crystal(s) (50). A change in oscillating characteristics of the crystal(s) (50), following interaction between the first and second members of the interaction pair, detects presence of the individual analyte(s).

Abstract: Binding between two members of a recognition pair, e.g. antigen-antibody is determined by utilizing a probe which includes a piezoelectric crystal with electrodes on two opposite faces of the crystal. The crystal carries one or more metal plates which may be the same or different than the electrodes, the metal plates having immobilized thereon a first member of a recognition pair. Binding of a second member of the recognition pair to the first member, or dissociation between the two members and release of the second member from the probe, causes a change of immobilized mass which results in a change to the probe's resonance frequency.

Abstract: An apparatus, a system and a method for the detection of an analyte in air comprising an air sampling system (1) comprising a mouthpiece (10) and a fan, a first enrichment stage (11) for enrichment of the analyte comprising a thermally regulated adsorption/desorption filter (20) creating a non-laminar gas flow for adsorption of the analyte, a heat source for heating the filter to evaporate the analyte, a second enrichment stage (30) for the further enrichment of the gaseous analyte comprising a cold trap (32) for condensing the analyte, extraction of the condensed material with a solvent, and collecting the solution, and analyzing the collected liquid sample with an analytical detection system, are disclosed. Further, an adsoption/desorption filter creating a non-laminar gas flow comprising a winding (21) of a resistance wire coated with an active material electric heating of the wire, is described. A specific application is detection of a gaseous component of explosives or mines, e.g. TNT, in air.