Instrument calibration method for dry biochemical analyzer - Database & Sql Blog Articles

Instrument calibration method for dry biochemical analyzer

At present, the country has not yet developed a dry biochemical analyzer.

Instrument measurement

Verification procedures or calibration specifications. To this end, we refer to the corresponding national instrument metrology verification procedures, such as

JJG464-2011

"Semi-automatic biochemical analyzer verification procedures",

JJG1051-2009

The "Electrochemical Analyzer Verification Protocol" determines the measurement performance of the dry biochemical analyzer by several aspects such as instrument accuracy, instrument repeatability and linearity. Calibration samples were selected from serum-based national secondary standards with fixed-value data. According to the reaction principle of the dry biochemical analyzer, the corresponding standard substances, such as human serum glucose standard substances, are used.

(

End point method

)

Potassium-sodium chloride standard substance

(

Potential method

)

,Alanine aminotransferase

(

Rate method

)

.

Instrument calibration

When the ambient temperature is

15

°C～

30

Between °C, and the temperature does not change more than ±

5

°C. After the dry biochemical analyzer is turned on, it is preheated and calibrated as required. The sample and the film are also required to be equilibrated at room temperature according to the requirements of the instrument.

First, the instrument indication error

(

Experimental data see table

1)

The insignificant error indicates the extent to which the instrument's test results are close to the true value, usually expressed as the relative error of the measurement results. When the instrument is calibrated, the standard material is continuously determined according to the operating instructions of the instrument.

3

Then, the average value of each measured value is obtained separately, and is calculated by the following formula

:

Second, instrument repeatability

(

Experimental data see table

2)

The repeatability of the measuring instrument refers to the ability of the measuring instrument to provide similar value under the same measurement conditions, reflecting the random error component of the measuring instrument, which can be quantified by the non-distributive dispersion. When the instrument is calibrated, the standard material is continuously determined according to the operating instructions of the instrument.

7

Second, the standard deviation is calculated according to the Bessel formula, and the repeatability is expressed by the relative standard deviation.

:

Third, linear

(

Experimental data see table

3)

The linear index and the quantity are proportional and linear. When the instrument is calibrated, select the series concentration standard solution separately, or dilute the high value sample of the standard solution according to the method provided by the manufacturer.

5

Samples of different concentrations were tested separately. Continuous measurement

3

Times, take the average value as the measured value. A set of measured values ​​of different concentrations was obtained. Linear Regression Analysis Method for Calculating Linear Regression Parameters of Samples

(a(

Slope

)

with

h(

intercept

)

Linear correlation coefficient

y

Said that the method is as follows

:

Fourth, the conclusion

According to the above method, the non-value error, repeatability, linearity and the like of the dry biochemical analyzer are obtained, which meets the requirements of the dry chemical analyzer medical industry standard. Since there is currently no comprehensive evaluation of the standard substances of dry biochemical analyzers in China, only some traceable methods are selected in this paper.

SI

The standard material of the unit is subject to instrument calibration or instrument calibration of the dry biochemical analyzer, which has certain limitations. In order to ensure the accuracy of the test results, the following points should be noted during the calibration process of the instrument.

:

1.

Different dry biochemical analyzers require different temperature and equilibration times for samples and wafers before testing. Room temperature should be balanced strictly according to the instrument manual.

2.

The standard solution added to the dry reagent strip should also be controlled for the addition amount and residence time as required by the instrument manual.

3.

For solution dilution, the method should be performed by the manufacturer to control the matrix effect.

For more information on instrument calibration methods for dry biochemical analyzers, please download the attachment: