A test system for the semi-automatic analysis of chemical constituents in a test fluid which comprises test devices having test reagents and code means associated therewith and an instrument which receives the test devices and is programmed by the device code means for automatically reading the particular test reagents associated with the particular test device being used. Preferably the test reagents are in a dry form, immobilized in or on a carrier member which upon contact with the test fluid can be manually presented to the instrument. Another preferable embodiment of the present device comprises the use of the code means to calibrate the instrument each time a test device is introduced thereto.
A test strip of the type which is dipped into a liquid such as urine for indicating by color information with respect to the liquid. The test strip has a transparent backing on one side of which is located a color-reaction paper with a fastening layer situated between the paper and the backing for fastening the paper to the backing. The fastening layer is opaque and non-reflecting with respect to light, so that while light can pass freely through the backing it will reflected by the color-reaction paper without passing through the backing. The test strip is moved perpendicularly across an optical axis along which light is directed with the light traveling first through the transparent backing and then being reflected by the color-reaction paper. Signals are generated from the light passing through the backing and the light reflected by the color-reaction paper, with the timing of the signal from the reflected light being controlled by the signal from the light which has passed through the transparent backing. The signal from the light which has traveled through the backing is utilized to initiate a time interval after which the signal from the reflected light is generated so as to assure that the operation of the structure providing the signal from the reflected light takes place when the color-reaction paper intersects the optical axis.
A method that provides techniques for determination of urinary constituents (Blood (Red Blood Cells/Hemoglobin), Leukocytes, pH, Specific Gravity, Bacterial Reductase/Nitrite/Indole activity, Total Ketone Bodies, Protein, and Glucose) at low chemically significant levels with a carrier independent reagent system that can be placed on a high throughput autoanalyzers. Thus, giving the analyst the ability to run multiple urinary assays on a single sample of urine simultaneously with the ability to compare to reference standards on the same run. This system is designed to neutralize urinary interfering substances. This method is fast, efficient, an adaptable to many of the currently available discrete and continuous flow automated analyzers, effective at sample to reagent ratios of 1 to 13 or more. This method is applicable to samples with high turbidity, high ionic strength, high color content, wide pH extremes, and buffer strengths, among other interfering substances.
A method for correction of calibration curve in a dry analytical process for quantitative analysis of analyte in a liquid sample such as blood is disclosed. In the method, a calibration curve which has been previously determined for analysis of the analyte using a standard dry analytical element is corrected for application to a dry analytical element having deviated from the standard dry analytical element in its sensitivity to the analyte due to unintentional denaturation, variation, etc., utilizing an optical density determined on the above deviated dry analytical element which has not received spotting of a liquid sample containing the analyte.
Improved apparatus for automatically calibrating and verifying the calibration of a chemical analyzer of the type which determines the concentration of a component in chemical or biological samples, e.g. concentration of glucose in blood or urine, wherein a sample changer sequentially advances samples into position for analysis. Calibration of the analyzer is performed by measuring a calibration standard of known concentration and generating a conversion factor therefor which converts the measured value of the standard to the known value thereof. Means is provided for storing conversion factors and proper calibration of the analyzer is verified by comparing successive conversion factors. If the compared conversion factors differ by more than a predetermined amount, the sample changer is halted and the calibration standard is remeasured. Measurement of the calibration standard is repeated until either two successive calibration factors are generated which differ by less than the predetermined amount, or until a predetermined number of unsuccessful measurements are made at which time the analyzer is stopped.
A method of distinguishing between strips for different assays in an automated instrument, wherein characteristics to which the instrument is sensitive are selectively introduced in microwells of individual microstrips which are pretreated with a specific antigen or antibody for a particular test. On each microstrip, the wells having the characteristic collectively define a multi-bit code which corresponds to a particular condition or disease to be tested for. The automated instrument reads the characteristic from the selected wells and thus determines what test is to be conducted. The marks may have optical, radioactive, luminescent, fluorescent, or magnetic characteristics, in accordance with the test to be conducted.
