Calibration Specification for Fully Automatic Biochemical Analyzer

Calibration Specification for Fully Automatic Biochemical Analyzer

The fully automatic biochemical analyzer belongs to medical specialized measuring instruments. Below isDetailed introduction of calibration specifications for fully automatic biochemical analyzers:

1. Scope

This specification applies to the calibration of fully automatic biochemical analyzers based on Lambert Beer's law as the quantitative principle, and is not applicable to the calibration of dry biochemical analyzers based on reflectance photometry as the quantitative principle.

2. Reference files

JJG 464-2011 semi-automatic biochemical analyzer

JJF 1071-2010 National Metrology Calibration Specification Compilation Rules

JJF 1059.1-2012 Evaluation and Representation of Measurement Uncertainty

YY/T 0654-2017 Fully Automatic Biochemical Analyzer

OIML R135:2004 (E) Spectrometer for Medical Laboratories

For all referenced documents with dates, only the version with dates is applicable to this specification; For all reference documents without a date, the latest version (including all modifications) shall apply to this specification.

3. Terminology and measurement units

The following terms and definitions apply to this specification.

3.1 Fully automatic biochemical analyzer

All analysis processes, including sample and reagent addition, mutual reaction, chemical and biological analysis, result calculation, and result readout, have been implemented with automated biochemical analyzers.

3.2 Absorbance

The ratio of transmitted light intensity to incident light intensity is called transmittance, and the commonly used logarithm of the reciprocal of transmittance is called absorbance.

4. Overview

The fully automatic biochemical analyzer (hereinafter referred to as the analyzer) follows the principle of Lambert Beer's law based on the characteristic absorption spectra of the measured substance in the ultraviolet and visible light regions. It compares samples of unknown concentration with standard substances of known concentration or performs quantitative analysis based on the molar absorptivity method. The expression of Lambert Beer's law is as follows:

The types of analyzers are divided into discrete and flow type. Monochromatic devices are divided into filter type and grating type. The optical path form includes front or rear splitting. The reaction cup (which can also be used as a colorimetric cup) can be reusable or disposable. Flow type refers to the process in which the chemical reactions of various test samples and reagents with the same measurement item are mixed and completed in the same pipeline; Split type refers to the chemical reaction between each sample to be tested and the reagent mixture being completed separately in their respective reaction vessels.

The front spectrophotometer divides the light emitted by the light source into monochromatic light through a monochromatic device. The monochromatic light is absorbed by the solution to be measured in the colorimetric cup, reducing the intensity of monochromatic light. By measuring the intensity of monochromatic light before and after absorption through a detector, the absorbance value of the test solution can be obtained; The post splitting instrument first shines a composite beam of light onto the colorimetric cup, then splits the light with a grating, and detects it with a diode array detector behind the grating.

The analyzer consists of multiple systems such as injection, temperature control, reaction, detection, and cleaning. According to Lambert Beer's law, the concentration of the analyte can be further calculated.

5. Measurement characteristics

5.1 Error in absorbance indication

When the standard value of absorbance is 0.5, the maximum allowable error of absorbance is ± 0.025;When the absorbance standard value is 1.0,The maximum allowable error for absorbance is±0.07.

5.2 Repeatability of absorbance

The measurement repeatability of absorbance 1.0 is ≤ 1.5%.

5.3 Linear Error

The absolute value of linear error is ≤ 5%.

5.4 ALT and GLU measurement indication errors and repeatability

Alanine aminotransferase（ALT）The measurement error and repeatability requirements for glucose (GLU) are shown in Table 2.

6. Calibration conditions

6.1 Environmental conditions

Temperature: 15 ℃~30 ℃;

Relative humidity: 40%~85%;

Other: No direct sunlight, no corrosive gases, no vibration or electromagnetic interference.

Note: If the conditions are inconsistent with the product specifications stated by the manufacturer, the product specifications shall prevail.

6.2 Standard substances

6.2.1 Biochemical analyzer calibration standard substance (absorbance standard solution): nominal absorbance values of 0.5 and 1.0, U,≤2%，k=2。

6.2.2 Standard substance for calibration of fully automatic biochemical analyzer: alanine aminotransferase in serum, U≤6%，k=2; Glucose in serum, U≤4%，k=2。

6.2.3 Linear error standard substance for calibration of fully automatic biochemical analyzer: Orange G absorbance standard substance, with at least 5 absorbance levels, minimum absorbance>0.1, maximum absorbance>2.0, and uniform coverage within the absorbance range (0.1~2.0), U,≤3%，k=2.

Note: Standard substances approved and issued by the national metrology administrative department should be used.