Abstract: We disclose apparatus that includes: (a) an enclosure including an aperture; (b) a prism mounted in the enclosure so that a surface of the prism is exposed through the aperture; (c) an optical assembly contained within the enclosure, the optical assembly including a radiation source and a radiation detector, the source being configured to direct radiation towards the prism and the detector being configured to detect radiation from the source reflected from the exposed surface of the prism; and (d) an electronic processor contained within the enclosure, the electronic processor being in communication with the detector. The apparatus can be configured so that, during operation, the electronic processor determines information about a sample placed in contact with the exposed surface of the prism based on radiation reflected from the exposed prism surface while it is in contact with the sample.

Abstract: An apparatus and method are disclosed for localizing an element of interest in a sample by comparing XRF spectra acquired from at least two distinct but overlapping inspection volumes. The inspection volumes are varied by changing the geometry of the exciting x-ray and/or fluoresced x-ray beam(s), which may be accomplished by repositioning multi-apertured collimators. Comparison of the XRF spectra acquired from different inspection volumes provides an indication as to whether the element of interest (e.g., lead) is present in a coating layer, in the underlying bulk material, or in both.

Abstract: Turbulent mixing condensation devices, methods, and systems adapted to condense a working fluid on particles from a sample gas to enlarge the particles for subsequent detection are provided. The device includes a vapor generator adapted to produce a working-fluid saturated carrier gas and a condensation chamber. The working-fluid saturated carrier gas is mixed with a sample gas containing particles to be detected and is then introduced to the condensation chamber. The operating conditions are controlled to enhance the condensation of the working fluid on the particles. The particles are typically forwarded to a particle detection device to detect at least one characteristic, for example, the size, of the particles. The flow of carrier gas to the vapor generator may be regulated to vary the degree of saturation of the carrier gas with working fluid.

Abstract: An optical emission spectroscopic system contains multiple distinct light paths that provide increased light to a spectrometer, thereby increasing sensitivity and signal-to-noise of the system.

Abstract: A method is provided for screening lead concentration compliance of objects, particularly consumer products such as toys, using x-ray fluorescence (XRF) analysis. The measured intensity ratio of the characteristic L? and L? x-rays of lead provides an indication of whether the lead is located primarily in a coating (e.g., paint) layer on the object, or in a thin or thick bulk material. If the intensity ratio indicates that the lead is located in a coating layer or distributed in a thin bulk material, an areal density of lead is determined from at least one of the characteristic x-ray intensities, and the measured areal density is compared to specified lower and upper limits to determine whether the object is unambiguously compliant, unambiguously non-compliant, or indeterminate.

Abstract: Methods of using an addressable array of biopolymers which has been exposed to a sample, and apparatus and computer program products for use of the arrays. In one embodiment the method includes detecting signals from the exposed array to obtain a signal image of the array. The array signal image is saved in a memory. Based on the detected signals, a shape of each region in one or more sets of multiple regions on the array signal image is established. A definition of the shapes of the established regions of each set is saved in a memory. Each region of each set is processed according to a corresponding routine for that set.

Abstract: A method of interrogating an addressable array unit having a transparent substrate with a back surface, and an array with a plurality of different chemical features on a front surface. The method may include illuminating the features while the array is dry, with an interrogating light which is directed through the substrate from the back surface and onto the chemical features on the front surface. The light emitted from respective features in response to the interrogating light may be detected, which detected light has passed from the front surface, through the substrate and out the back surface. In one arrangement the light is emitted from locations of the features which are spaced from the front surface a distance of less than one-eighth of the wavelength of the illuminating light in a gas or a vacuum which is in contact with the dry array. Other methods and a package containing an addressable array are also provided.

Abstract: A drop deposition apparatus, and a method and computer program products using the drop deposition apparatus, for fabricating at least one addressable array of biopolymers on a substrate. The drop deposition apparatus has a drop dispenser unit and a sensing element. The method comprises includes for each of multiple addresses, dispensing droplets carrying the biopolymers or biopolymer precursors from a drop dispenser unit onto the sensing element, and onto the substrate so as to fabricate the array. Electrical signals resulting from dispensed droplets striking the sensing element are detected. A performance characteristic of the deposition apparatus is evaluated based on the detected signals.

Abstract: Arrays having multiple biopolymer features on a substrate, including elongated features which have a length/width ratio greater than 1.3 or more. Such arrays may be oriented in various directions and of shapes described, and fabricated using apparatus, methods, or computer program products of the invention.

Abstract: The invention provides an apparatus and method for conducting chemical or biochemical reactions on a solid surface within an enclosed chamber. The invention may be used in conducting hybridization reactions, as of biopolymers such as DNA, RNA, oligonucleotides, peptides, polypeptides, proteins, antibodies, and the like. In another aspect, the invention provides an improved method for mixing a thin film of solution, as in a hybridization chamber. The invention further provides a kit for carrying out the methods of the invention.

Abstract: A method of fabricating an addressable array of biopolymers on a substrate using a biomonomer with a first linking group which must be activated for linking to a substrate bound moiety, and apparatus and computer program products for executing the method. The method includes forming on a region of the substrate carrying the substrate bound moiety, a solid activator composition. A biomonomer containing fluid composition is deposited on the region so that the solid activator activates the first linking group and the biomonomer links to the substrate bound moiety. The foregoing steps may be repeated, wherein a biomonomer deposited and linked to the substrate bound moiety in one cycle is the substrate bound moiety for the next cycle, so as to form the biopolymer.

Abstract: A method and apparatus for fabricating an array of biopolymers on a substrate using a biopolymer or biomonomer fluid, and using a dispensing head. The head has a reservoir chamber and at least one jet which can dispense droplets onto a substrate. The jet includes a capillary delivery chamber communicating with the reservoir chamber, which delivery chamber has an orifice. The jet further includes an ejector which, when activated, causes a droplet to be ejected from the orifice. The method includes loading the head by positioning the head with the orifice adjacent and facing a biomonomer or biopolymer fluid, and providing a load pressure to the reservoir chamber. The load pressure is sufficiently negative such that the fluid is drawn into the reservoir chamber through the orifice and delivery chamber, while simultaneously being insufficient to result in ambient atmosphere entering the delivery chamber through the orifice once the head has been loaded and no further fluid is facing and adjacent the orifice.

Abstract: A method of using an addressable array of biopolymers on a substrate includes receiving the addressable array and an associated machine readable identifier carried on an array substrate or array housing. The array is exposed to a sample and read, and the identifier machine read as an identifier signal. Biological function data for one or more of the biopolymers is retrieved from a memory based on the identifier signal. Other methods in which first and updated sets of feature characteristic data may readily be provided to array users, and methods of generating arrays are also provided, as are apparatus and computer program products which can execute a method for generating or using arrays.

Abstract: Array units and methods are provided which have constructions to reduce or take advantage of Fresnel reflection. The array units may have a subtantially unreflective substrate. In one arrangement a transparent spacer layer is provided while in another an anti-reflective layer is present.

Abstract: A method and apparatus for fabricating an array of biopolymers on a substrate using a biopolymer or biomonomer fluid, and using a dispensing head. The head has a reservoir chamber and at least one jet which can dispense droplets onto a substrate. The jet includes a capillary delivery chamber communicating with the reservoir chamber, which delivery chamber has an orifice. The jet further includes an ejector which, when activated, causes a droplet to be ejected from the orifice. The method includes loading the head by positioning the head with the orifice adjacent and facing a biomonomer or biopolymer fluid, and providing a load pressure to the reservoir chamber. The load pressure is sufficiently negative such that the fluid is drawn into the reservoir chamber through the orifice and delivery chamber, while simultaneously being insufficient to result in ambient atmosphere entering the delivery chamber through the orifice once the head has been loaded and no further fluid is facing and adjacent the orifice.

Abstract: A method of fabricating an addressable array of biopolymers on a substrate using a biomonomer with a first linking group which must be activated for linking to a substrate bound moiety, and apparatus and computer program products for executing the method. The method includes forming on a region of the substrate carrying the substrate bound moiety, a solid activator composition. A biomonomer containing fluid composition is deposited on the region so that the solid activator activates the first linking group and the biomonomer links to the substrate bound moiety. The foregoing steps may be repeated, wherein a biomonomer deposited and linked to the substrate bound moiety in one cycle is the substrate bound moiety for the next cycle, so as to form the biopolymer.

Abstract: Low surface energy functionalized surfaces on solid supports are provided by treating a solid support having hydrophilic moieties on its surface with a derivatizing composition containing a mixture of silanes. A first silane provides the desired reduction in surface energy, while the second silane enables functionalization with molecular moieties of interest, such as small molecules, initial monomers to be used in the solid phase synthesis of oligomers, or intact oligomers. Molecular moieties of interest may be attached through cleavable sites. Derivatizing compositions for carrying out the surface functionalization process are provided as well.

Abstract: The invention provides an apparatus and method for conducting chemical or biochemical reactions on a solid surface within an enclosed chamber. The invention may be used in conducting hybridization reactions, as of biopolymers such as DNA, RNA, oligonucleotides, peptides, polypeptides, proteins, antibodies, and the like. In another aspect, the invention provides an improved method for mixing a thin film of solution, as in a hybridization chamber. The invention further provides a kit for carrying out the methods of the invention.

Abstract: An assay plate for detecting the presence of a mobile reactant that binds to a immobilized reactant and the methods of making and using the same. An assay plate according to the present invention includes a substrate and at least one dried aliquot of the immobilized reactant, the immobilized reactant being bound to the surface of the substrate. The immobilized reactant binds the mobile reactant when a solution containing the mobile reactant is brought into contact with the immobilized reactant. The mobile and immobilized reactants may be any pair of biological compounds that have a specific affinity for one another For example the reactants may be nucleic acids or antibody-antigen pairs.