Abstract: A test strip for detecting an analyte (e.g., blood glucose) in a liquid sample (e.g., whole blood) includes an analytical portion (e.g., a reagent pad), a first edge with a first edge indentation and a second edge with a second edge indentation. The test strip also includes a first capillary channel adapted for providing fluid communication between the first edge indentation and the analytical portion, as well as a second capillary channel adapted for providing fluid communication between the second edge indentation and the analytical portion. Furthermore, the first and second edges are in an opposing relationship (e.g., on left-hand and right-hand sides of the test strip). Also, a test strip and meter combination for detecting an analyte in a liquid sample. The combination includes a test strip with an analytical portion and first and second edges. The first and second edges of the test strip each include an edge indentation with a sample application region.

Abstract: The invention provides testing devices useful in colorimeteric measurements of analytes in which at least a portion of the device's support is of a reflectivity that will not interfere with the meter's error detecting means

Abstract: A reagent strip is provided for measuring the concentration of an analyte in a liquid test sample, such as glucose or cholesterol in whole blood. The reagent strip includes a testing pad containing a color-forming reagent system specific to the analyte. The testing pad is disposed so that a side with relatively small pores defines a testing surface and an opposite side with relatively larger pores defines a sample-receiving surface. A porous sample transport medium is attached to the sample-receiving surface. A change in coloration caused by the color-forming reagent system at the testing surface is quantitatively related to the concentration of the analyte in the liquid test sample. The reagent strip may optionally include a rigid support member which facilitates evaluation of the change in coloration by mechanical viewing means. Also provided is a method for determining the concentration of an analyte in a liquid test sample.

Abstract: A dye couple compound is provided for use in a test device containing a reagent system for detecting the presence or quantity of an analyte in a sample. The reagent system comprises one or more enzymes which, in the presence of the analyte, produce an oxidizing agent in quantities indicative of the quantity of analyte in the sample. The compound of choice is meta?3-methyl 2-benzothiazolinone hydrozone!N-sulfonyl benzenesulfonate monosodium.

Abstract: A reagent strip for measuring glucose concentration in whole blood has reduced interference of hematocrit with the glucose measurement. When a biological fluid contacts the strip, it causes, in a reagent impregnated in the strip, a color change that is a measure of the glucose concentration in the fluid. However, the color change is also affected by the red blood cell concentration (hematocrit), thereby reducing the accuracy of the glucose measurement. The hematocrit effect is reduced by adding to the reagent an acrylic acid polymer.

Abstract: A chemical timer for a direct-reading reagent test strip changes color a predetermined time after a biological fluid is applied to the strip. The strip measures the concentration of an analyte in the fluid. The timer is a dry coating of an indicator, an enzyme-containing reagent that when hydrated can react with glucose to change the color of the indicator, an inhibitor to inhibit the change in color of the indicator, glucose, and optionally, an aldose that does not react with the enzyme in the reagent. Preferably, the reagent and glucose are present in excess in the coating, and the time it takes for the timer color to change can be controlled by the inhibitor concentration. The aldose provides timer stability, probably by interfering with glycosylation by the glucose in the dry state.

Abstract: A control solution for use with a photometric blood glucose strip contains glucose in an aqueous suspension of carbon black. The control solution mimics blood when applied to a whole blood glucose test strip, which is then inserted into a meter. A meter reading within a predetermined range indicates that meter and strip are operating satisfactorily. Preferably the control solution is buffered to a neutral pH and includes chloride ion to provide a stable end point for the glucose reaction. Depending on the glucose concentration, the solution checks meter and strip operation at high, low, and normal blood glucose levels.

Abstract: A dye couple compound is provided for use in a test device containing a reagent system for detecting the presence or quantity of an analyte in a sample. The reagent system comprises one or more enzymes which, in the presence of the analyte, produce an oxidizing agent in quantities indicative of the quantity of analyte in the sample. The compound of choice is meta[3-methyl 2-benzothiazolinone hydrozone]N-sulfonyl benzenesulfonate monosodium.

Abstract: A dye couple, comprising 3-methyl-2-benzothiazolinone hydrazone (MBTH) and 8-anilino-l-naphthalenesulfonate (ANS), is used as an indicator in a reaction cascade producing a strong oxidizing agent, such as hydrogen peroxide or other peroxides or perborates. The strong oxidizing agent reacts with the dye couple to produce a blue dye stuff. The MBTH-ANS dye couple exhibits strong and flat spectral absorption at the region of about 600 to 650 nm. This region is free of blood color interference, which enables one to measure glucose and other analytes that react with an oxidase enzyme to produce the strong oxidizing agent, through the use of LED optics, accurately without much optic calibration. Further, the MBTH and ANS are very soluble in aqueous solution, yet become insoluble upon oxidative coupling. The poor solubility minimizes dye fading, thus providing a stable endpoint.