Fuji Electric Co., Ltd.

Toshiyoshi Hamada

Nobuhiko Tsuji

Keijiroh Nakamura

Keiichi Ishida

Koichi Endoh

A blood sugar analyzer has a reaction cell which houses a fixed enzyme membrane and measuring electrode and which receives a blood specimen, to cause a chemical reaction between the specimen and membrane for measuring the blood sugar concentration in the specimen on the basis of the reaction current generated in the electrode by the reaction. The analyzer also monitors the temperature in the cell and the sensitivity of the electrode, and a printer prints out data on the temperature and sensitivity. A digital control device controls overall operation of the analyzer.

System for controlling a printer in a blood sugar analyzer

A process of calibrating a blood sugar analyzing apparatus, in which the blood sugar concentration in a blood specimen is measured with a fixed enzyme membrane sensor and corrected by calibration means, said blood sugar analyzing apparatus providing a linear relationship between measured and actual blood sugar concentrations in a range of blood sugar concentrations which are lower than a predetermined blood sugar concentration, and producing a deviation from said linear relationship in a range of blood sugar concentrations higher than said predetermined blood sugar concentration, in that said process comprises the steps of effecting a plurality of measurements of standard solutions having known low blood sugar concentrations in said blood sugar analyzing apparatus, obtaining an average value of the results of the measurements with said calibration means, determining a first correction coefficient (k.sub.1) to correct a deviation of said average value from the reference blood sugar concentration, thereafter measuring a blood specimen, and multiplying the result of the measurement by said correction coefficient with said calibration means when said result of the measurement is less than said predetermined blood sugar concentration and by a second calibration coefficient (K.sub.2) when the result of the measurement exceeds said predetermined blood sugar concentration.

Process of calibrating a blood sugar analyzing apparatus

A blood sugar analyzing apparatus has a reaction cell which houses a fixed enzyme membrane sensor and a measuring electrode which receives a blood specimen which causes a chemical reaction between the blood specimen and said fixed enzyme membrane for measuring the blood sugar concentration in the specimen on the basis of a reaction current signal generated in the sensor by the chemical reaction. The analyzing apparatus has a microcomputer for calculating a conversion coefficient used for converting the reaction current into a blood sugar concentration value by introducing a standard solution having a known blood sugar concentration, for storing data representing the value of said conversion coefficient, for calculating a blood sugar concentration value of a test specimen based upon the stored conversion coefficient value and reaction current from the test specimen. A display and printer provide a read-out of the blood sugar concentration value obtained. The microcomputer controls temperature and timing of the measurement process, as well as other control functions.

Blood sugar analyzer having fixed enzyme membrane sensor

A blood sugar analyzer system for measuring the blood sugar concentration level in a blood specimen is provided. A sensor having a fixed enzyme membrane and a measuring electrode generates a reaction current proportional to the blood sugar level of the specimen, and a sampling mechanism samples the sensor output at regular intervals. A memory receives data from the sampling and divides the data into a group of new data and a group of old data. A calculating mechanism calculates the average value of each group, and the difference between the averages. When the difference exceeds a predetermined value, the latest sensed data value is selected as the rising point of the chemical reaction between the fixed enzyme membrane of the sensor and the blood sugar of the specimen.

Blood sugar analyzing apparatus

An infrared gas analyzer includes side-by-side measuring and comparison vessles S, V containing sample and reference gases alternately exposed to infrared light through a rotary chopper CH. The end windows of the vessels are transparent, and a detector D containing two series chambers D1, D2 filled with a gas of the same kind as the component gas to be analyzed is axially disposed below the vessels. A capacitive diaphragm sensor is coupled between the chambers to detect pressure variation differences therebetween, and an adjustable reflecting means is disposed below the transparent bottom window of the second chamber to reflect back a portion of the light energy passing therethrough. The degree of reflection is suitably adjusted so that any interference gas component has an equal influence on the absorption curves of both chambers, whereby its effects are self-cancelling. The same structural concept of an adjustable reflecting means disposed below the bottom window of the second chamber may also be used to implement zero adjustment when a reference gas is circulated through the vessel.

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Tokyo, Japan

Toshiyoshi Hamada