code: -kanzulhussainpdfdownload description: 提取所有pdf文件到某个目录中 this invention relates to a method and apparatus for the detection and measurement of the concentration of analytes in a fluid. the invention may be used in the medical field, such as in the analysis of blood samples taken from patients for the diagnosis of disease, in the environmental field, or in any other analytical field where it is important to detect and measure the concentration of certain chemical species in fluids. there is a great need for an accurate, inexpensive and highly-sensitive means for measuring the concentration of certain chemical species in fluids. one such example is the need to detect and measure the concentration of glucose in blood. the concentration of glucose in blood may be used to determine if an individual is suffering from diabetes. the concentration of glucose in blood may be measured using the enzyme-catalyzed formation of a colored end product from a substrate. a chemical reaction for glucose detection by means of this enzyme-catalyzed reaction is described in the article "glucose oxidase", by william a. shafer, appearing in analytical chemistry, vol. 36, no. 4, april 1964. the article describes the formation of hydrogen peroxide by glucose and shows that the hydrogen peroxide reacts with a chromogenic substrate to form a chromogenic end product. the article contains no suggestion of a method for measuring the concentration of glucose in a sample. the article "an improved method for the enzymatic determination of glucose", by john s. lowe et al. appearing in analytical chemistry, vol. 35, no. 9, pp. 1841-1847, describes an analysis method for glucose, but does not indicate a means for measuring the glucose concentration. a method for the measurement of glucose concentration by first oxidizing the glucose to form gluconic acid and then forming a color complex between the oxidized glucose and an acidic dye is described in the article "a reagent for the enzymatic determination of glucose", by k. e. rieder et al. 1, pp. 132-135, january 1963. it is important to have a sensitive means for measuring the concentration of glucose in fluids. in the early stages of diabetes, the concentration of glucose in the blood is often at a very low level. therefore, a sensitive means for measuring glucose in blood is important for the early diagnosis of diabetes. the sensitivity of an assay is a measure of the ability of an assay to measure the concentration of an analyte present in a test sample. the sensitivity of a glucose assay depends on the concentration of hydrogen peroxide formed during the reaction catalyzed by the enzyme. the concentration of hydrogen peroxide is determined by the amount of glucose which is oxidized to form gluconic acid. in the assay of a sample for glucose using an oxidase enzyme, the minimum amount of glucose in the sample that is oxidized to produce a measurable amount of hydrogen peroxide is known as the "detection limit". the detection limit is the minimum concentration of glucose in a test sample at which a positive test result is achieved with a given enzyme assay. a high sensitivity of an enzyme-catalyzed glucose assay is important for the early diagnosis of diabetes. one disadvantage of known glucose assays is that they are relatively insensitive to the presence of other interfering species.