Abstract:
The present invention relates to a process to determine the concentration of any substance in a colorimetric, turbidimetric or nephelometric reaction using a fluorometric detector to measure fluorescence intensity. In particular, a change in color can be monitored by observing the measurement of fluorescence intensity of a fluorophore in an inert matrix. The absorption spectrum of the chromophore may overlap the excitation and/or emission spectrum of the fluorophore, thereby allowing the change in fluoroscence to be related to the intensity of color in the reaction and thus related to the quantity of the substance of interest.
Abstract:
Nucleic acid primers of complementary sequence to portions of the gene encoding a semiconserved region of B. burgdorferi flagellin are utilized to amplify target sequences of nucleic acids extracted from infective sites of Lyme borreliosis, which are then probed with a nucleic acid tracer conjugated to signal-generating molecules for highly specific detection of B. burgdorferi.
Abstract:
A method and apparatus for assaying the sensitivity of biopsied tumor cells to chemotherapeutic agents using a predetermined amount of chemotherapeutic agent in an easily deliverable form is disclosed and claimed.
Abstract:
A method to use a reaction by-product as a calibrator in an automated enzymatic assay is described. In particular, the reaction by-product pyruvate is used as an instrument calibration standard to measure the activity of alanine aminotransferase. Use of this method eliminates errors due to inaccurate pipetting and corrects for small optical deviations from the wavelength of interest in the instrument. Left uncorrected, pipetting error and optical deviation negatively impact the accuracy of the enzyme activity calculation. In the fluorescence mode, calibration with a pyruvate standard also eliminates having to use unstable NADH standards. The pyruvate calibration standard of this invention is shown to be stable in standard stability testing. This method can be extended to a number of other automated enzymatic assays. Like alanine aminotransferase, the accuracy of the activity calculation for other enzymes should be increased by use of this procedure.
Abstract:
The compound 2,3,5,6-tetrahydroxy-1,4-quinone, its derivatives and structural analogs are used as activators for intrinsic blood coagulation and as diagnostic reagents for the activated partial thromboplastin time test of blood coagulation.
Abstract:
Methods and compositions are provided for specific binding assays in which specific binding reagents are immobilized on a solid phase. Immobilization is facilitated by coupling bifunctional reagents to specific binding assay proteins thereby chemically cross-linking the specific binding assay reagents. Such cross-linked specific binding assay reagents provide the advantage of performing assays without the use of secondary reagents. This provides for enhanced sensitivity through minimizing nonspecific background interference with the solid phase or with the target samples.
Abstract:
A precision liquid reagent fluid dispensing apparatus (10) and method includes a continuously operating pump (16) inducting and pressurizing ambient air. The pressurized air is delivered at a first location into a flow-through volume (18) with provision to substantially completely abate at a second location any noncontinuous air flow or air pressure variations from the pump. A long-lived pressure sensor (32) which is substantially free of drift is associated with the flow through volume at a third location and provides a signal indicative of sensed air pressure. A controller (36) by reference to a calibration standard for the sensor provides a time-variant control signal in response to the sensed air pressure. At a fourth location a duty cycle valve (38) vents pressurized air from the flow through volume in response to the control signal to provide at the second location a precisely regulated dispensing air pressure. The dispensing air pressure is applied via a reagent liquid container (46) and closure member (62) to a liquid reagent to pressurize this reagent for dispensing at a precise rate via a dispensing valve (82). The dispensing valve is sealingly carried by the closure member to reduce leakage paths and corrosion opportunities in the apparatus of the present invention.
Abstract:
The present invention provides a stable control serum or plasma for tumor diagnosis, wherein the control contains the tumor markers relevant for the diagnosis of tumors. The serum or plasma has a reduced lipid content. The present invention also provides for a method of making the control.
Abstract:
A composition and method are disclosed to reduce the effects that endogenous alkaline phosphatase found in some human bodily fluid samples have on solid phase immunoassay systems. The composition comprises a detergent, inhibitors to alkaline phosphatase, and a buffer and may contain a substrate to alkaline phosphatase.
Abstract:
A cartridge for holding an analytical sample during a diagnostic assay comprises a panel with a number of adjacent wells in its upper side. The wells have an upper opening and a lower opening, and the lower opening extends to the underside of the panel. A filter membrane extends across the lower openings of the wells so that liquids contained in the wells may be drawn through the filter, thereby concentrating suspended solids near the lower openings of the wells. The panel includes a supporting wall for supporting the panel on a non-integral, external surface, which does not form a part of the panel.