Abstract: A method and apparatus for the measurement of radiation, especially fluorescence from samples in assays, wherein a plurality of micro-sample light emitting sites are imaged simultaneously onto a detector array by a plurality of miniature objectives, one for each sample site and focussed thereon, producing parallel beams of light arranged in parallel and spaced apart, which beams are focussed at a pinhole aperture and then reconstituted as parallel beams for incidence on the detector array.

Abstract: A fiber optic epi-fluorescence imaging system in which the optical fibers are rearranged so that the system can be used for measuring luminescence samples. The system comprises at least two optical fibers (32, 46) or bundles of fibers which lead to a CCD camera (74), the fibers or bundles of fibers from all samples being arranged in two sets, a first set which are formed from a non-fluorescing material and a second set which are formed from a material which may fluoresce but enables the fibers formed therefrom to have a higher numerical aperature than those of the first set.

Abstract: A system for imaging radiation emitted by assay couples into a photoelectric detector, the system including a fibre optic bundle (100) for conveying light to the detector, wherein a microlens (118), preferably a drum lens, is located at the impact end of the fibre optic bundle to match the field of view of the bundle to a potential area of interest in a sample.

Abstract: A fiber optic epi-fluorescence imaging system in which the optical fibers are rearranged so that the system can be used for measuring luminescence samples. The system comprises at least two optical fibers (32, 46) or bundles of fibers which lead to a CCD camera (74), the fibers or bundles of fibers from all samples being arranged in two sets, a first set which are formed from a non-fluorescing material and a second set which are formed from a material which may fluoresce but enables the fibers formed therefrom to have a higher numerical aperture than those of the first set.

Abstract: Apparatus for detecting light emitted by an assay sample is provided, in which light emitted by the sample is collected for transmission to a photosensitive detector such as a charge coupled device (CCD) (74) by an optical fiber 78 bundle. The cross-sectional area of the optical fiber bundle corresponds to the area of the sample, the end of which is located close to the sample for detecting any light emitted therefrom. Selected fibers (30) of those making up the bundle may be separated from the remainder and extend to a source of excitation radiation (76) to convey excitation radiation to the sample. The remaining fibers (32, 38) serve to collect emitted light and provide a light path to the photosensitive detector (74). A blocking filter and an interference filter are placed between the fiber bundle and the detector. The blocking filter may be between the bundle and the interference filter or between the latter and the detector.

Abstract: Apparatus for detecting light emitted by assay samples is provided, in which light emitted by the sample is collected for transmission to a charge coupled device camera (74) by an optical fiber bundle. The cross-sectional area of the optical fiber bundle corresponds to the area of the sample, the end of which is located close to the sample for detecting any light emitted therefrom, and selected fibers (30) of those making up the bundle are separated from the remainder and extend to a source of excitation radiation (76) and serve to convey excitation radiation (if required) directly to a corresponding plurality of points distributed over the are of the end face of the bundle and therefore over the area of the sample.

Abstract: An optical system for imaging a multiwell sample plate onto a CCD camera, wherein light from the illuminated sample plate (26) is imaged by one or more lenses (20,24) onto a fibre optic taper (22), bonded to the input face of the camera (28).

Abstract: A fiber optic coupling plate (24) has a sample viewing face for receiving light from a sample (12), an output window (18) for conveying sample originating (emitted) light to an imaging detector and an additional window through which excitation radiation can be projected. A primary light is provided through the plate made up of optical fibers which will convey light entering the viewing face, directly and with minimal loss, to the output window, and a secondary light path separate from the primary light path, by which excitation radiation entering the additional window is conveyed to the viewing face for irradiating the sample.

Abstract: Method of performing a biomedical assay comprising the steps of exciting the sample or samples with incident radiation of a given wavelength, thereby causing the sample to emit radiation of a different wavelength, measuring the quantity of light falling on a detector receiving the emitted radiation from the sample, thereby to produce a first measurement, illuminating the sample or samples with incident radiation in a manner which does not cause the sample to emit any significant radiation, again detecting the quantity of light falling on the detector, thereby to produce a second measurement and correcting the first measurement, with respect to the second measurement.

Abstract: The present invention provides a detection system comprising means (12) for supporting a multiple sample assay (11) in an inspection station, plural addressable photosensitive detector elements in an array (20) which is positioned relative to the inspection station, means (30, 32) for addressing the groups of elements at regularly occurring intervals of time so as to generate linked numerical values for analysis, means (44, 46) for computing the arithmetic mean of the linked numerical values read out, and means for supplying as output information the numerical value of the computed arithmetic mean of the linked values. A method of analyzing a multiple sample assay is also provided.

Abstract: A microvolume liquid handling system includes a microdispenser employing a piezoelectric transducer attached to a glass capillary, a positive displacement pump for priming and aspirating transfer liquid into the microdispenser, controlling the pressure of the liquid system, and washing the microdispenser between liquid transfers, and a pressure sensor to measure the liquid system pressure and produce a corresponding electrical signal. Dispensing of a single sub-nanoliter drop can be detected in real time. As the result of dispensing the liquid in sub-nanoliter droplets, the dispensed volume can be precisely controlled. The dispenser automatically detects the liquid surface of the transfer liquid, automatically aspirate, analyze desired volume of the transfer liquid, dispense the transfer liquid without contacting the destination vessel or its contents, and automatically wash off the transfer liquid from dispensing system after each transfer.

Abstract: An imaging system for fluorescence assays includes a fiber optic coupling plate (20, 24, 26) for transmitting radiation emitted by a sample (18) towards a camera. This is combined with an interference filter (22) so as to enable highly sensitive transmission of radiation to the camera, according to wavelength. The interference filter may be combined with a fiber optic coupling plate in which sample sites or wells of an array are viewed by separate fiber optic bundles, each bundle transmitting emitted light from a one sample or well to a discrete region of the field of view of the camera.

Abstract: The disclosed spotting instrument includes one or more sensors that are mechanically fixed to the instrument's printhead. The sensors enable the instrument to detect whether a substrate is mounted in a particular holder of the instrument's substrate station prior to attempting to print spots onto that substrate. Similarly, the sensors enable the instrument to detect whether a reservoir is mounted in a particular holder of the instrument's well station prior to attempting to collect a sample of target material from that reservoir. The sensors also enable the instrument to read bar code labels affixed to substrates or reservoirs mounted in the instrument.

Abstract: In one embodiment, a microvolume liquid handling system includes a microdispenser employing a piezoelectric transducer attached to a glass capillary, a positive displacement pump for priming and aspiring transfer liquid into the microdispenser, controlling the pressure of the liquid system and washing the microdispenser between liquid transfers, and a pressure sensor to measure the liquid system pressure and produce a corresponding electrical signal. The pressure signal is used to verify and quantify the microvolume of transfer liquid dispensed and is used to perform automated calibration and diagnostics on the microdispenser. In another embodiment of the microvolume liquid handling system, a system reservoir is connected with tubing to a pressure control system for controlling the liquid system pressure in the system reservoir. The system reservoir is coupled to one or more microdispenser through a distribution tube having a branched section for each microdispenser.

Abstract: A fibre optic coupling plate (24) has a sample viewing face for receiving light from a sample (12), an output window (18) for conveying sample originating (emitted) light to an imaging detector and an additional window through which excitation radiation can be projected. A primary light is provided through the plate made up of optical fibres which will convey light entering the viewing face, directly and with minimal loss, to the output window, and a secondary light path separate from the primary light path, by which excitation radiation entering the additional window is conveyed to the viewing face for irradiating the sample.

Abstract: A microarray storage device includes a cassette having top, bottom and opposite side walls, the front and rear of the cassette being open. The side walls are formed with a multiplicity of parallel rails spaced along the heights of the walls which define compartments in the cassette for supporting a multiplicity of microarrays one above the other. The depth of the cassette is such that the microarrays supported in the compartments project appreciably from the front and/or rear of the cassette. Integral springs are formed in the side walls of the cassette which press down directly on the side edge margins of the microarrays so as to releasably retain the microarrays in their respective compartments.

Abstract: A microplate forms a multiplicity of sample wells for holding samples to be assayed by light emissions or light transmission. The microplate comprises a unitary upper plate and a unitary lower plate. The unitary upper plate forms the side walls of the sample wells, while the unitary lower plate forms the bottom walls of the sample wells. The side walls are opaque so that light cannot be transmitted between adjacent wells through the side walls. The bottom walls are transparent to allow the transmission of light therethrough. Bands of opaque material surround the bottom wall of each well and are located below a level of an upper surface of, the bottom wall of each well. The bands of opaque material are constructed and arranged to block the transmission of light between adjacent wells through the lower plate.

Abstract: An arrangement senses a liquid level by monitoring the peak capacitance formed between a probe and the liquid as the probe approaches or departs from the liquid. In an automated system, a computer controls the position of a pipette probe for aspirating or dispensing liquid in the vessel. The charge developed via the capacitance on the probe is coupled to a capacitive sensor circuit which provides a peak detector with an amplified signal representing the peak capacitance between the probe and the liquid. This amplified signal is detected by a peak-capacitance discrimination circuit, the output of which is monitored by the computer for determining the precise position of the probe with respect to the liquid surface level. Other aspects of the present invention include a negative-static elimination circuit coupled to the output of a detector latch and a positive-static elimination circuit coupled to the input of the detector latch.

Abstract: A normalization system for multi-photodetector single photon counting luminescent measuring systems and a standard for use in the same. The method comprises calculating one or more counting ratios for each photodetector in the single photon counting system and multiplying counts of unknown samples by the inverse of the appropriate counting ratio. A counting ratio for a particular photodetector is calculated by dividing the count of a standard measured by the photodetector by the count of the same standard measured by a reference photodetector. The particular standard developed employs calcium tungstate:lead as a scintillator and tritium or carbon-14 thymidine as a means of exciting the scintillator. This standard has the advantages of providing a good model of typical luminescence chemistry and producing an emission pattern which is susceptible to single photon counting.