Selling unit: per 100ml
Common name: Cholinesterase ( CHE ) assay kit (rate method)
English name: CHE Reagent Kit (Kinetic Method)
3:1,4:1,5:1 can be used, commonly used ratio 4:1.
This kit is used to determine the viability of CHE in human serum or plasma.
Serum cholinesterase can be divided into two types: one exists in the gray matter of the central nervous system, sympathetic node, motor end plate, red blood cells, etc., mainly acting on acetylcholine, called true or acetylcholinesterase (ACHE); the other exists in the white matter of the central nervous system, plasma, liver, pancreas, mesentery, uterus, etc., in addition to acting on acetylcholine, can also act on other cholinesterases, on acetylcholine The specificity of acetylcholine hydrolysis is less than that of acetylcholinesterase, so it is called pseudocholinesterase or cholinesterase-like. Serum cholinesterase refers to PCHE, which is synthesized by the liver and present in the serum, and has pathological significance when activity is decreased. Cholinesterase is commonly used to detect poisoning by organophosphorus pesticides and is the most important indicator for monitoring the severity of poisoning and recovery from poisoning. In acute poisoning, cholinesterase levels can be greatly reduced. Nowadays, cholinesterase is mainly used for the detection of liver function. Serum cholinesterase activity is greatly reduced to 60% of normal in patients with severe hepatitis, and can be reduced to less than 10% or even lower in critically ill patients. Cholinesterase activity decreases in chronic active hepatitis and cirrhosis in the decompensated phase, so its determination has some reference value for the estimation of liver function and the prognosis of liver disease. CHE is also reduced in cases of starvation, malnutrition and burns. In addition, succinylcholine is a surgical muscle relaxant and can be hydrolyzed by cholinesterase. In patients with low cholinesterase, or with atypical genetic variants, weakly active isoenzymes are produced that do not hydrolyze the drug, resulting in persistent asphyxia and respiratory muscle paralysis after administration of the drug. For this reason, the sensitivity of the patient to the drug is determined preoperatively by measuring the activity of CHE and the inhibition of CHE by dibucaine and fluoride.
Cholinesterase (CHE) catalyzes the hydrolysis of butyrylthiocholine to yield propionic acid with thiocholine; the latter reacts with colorless 5,5′-dithio-2-nitrobenzoic acid to form yellow 5-Mercapto-2-nitrobenzoic acid (5-MNBA). The absorbance was measured at 404 (400~420) nm, and the rate of absorbance increase was proportional to the CHE activity. The cholinesterase activity in the sample can be calculated by monitoring the rate of absorbance rise at 404 (400-420) nm.
Reagent components included in the product.
* The components of the kits are not interchangeable between batches.
*Reagent components not included in the product, but necessary for the test: outsourced normal and abnormal QCs and calibrators.
Storage Conditions And Expiration Date
The kit is stored at 2-8°C away from light and is valid for one year.
Reagents that have been opened are careful not to be contaminated, and reagents are stable in the instrument compartment (2-8°C) for one month.
The reagents must not be frozen.
Hitachi 7180/7600; Olympus AU680/2700; Toshiba TBA120; Myriad BS2000M/480; Siemens ADVIA 1800/2400 series automatic biochemical analyzers.
Serum or heparin/EDTA anticoagulated plasma specimens to avoid hemolysis and as soon as possible separation. Stable for 6 hours at room temperature (15~25℃), 1 week at 2~8℃ and up to 1 year in frozen state (-20℃).
- Reagent preparation: liquid reagents are ready to use out of the bottle.
- test conditions: (different parameters on the machine can be requested according to different testing instruments)
Reagents and sample volumes can be increased or decreased in proportion to the requirements of different biochemical analyzers.
- Calibration procedure.
Landau calibrators are recommended.
- QC control procedures.
It is recommended that each laboratory establish its own quality control system and select appropriate quality control products for quality control. The measured values of QC products should be within the specified range. If outside the specified range, it is necessary to take appropriate measures or contact the manufacturer.
Sample concentration = (sample ΔA /min) / (standard ΔA /min) × standard concentration
Positive Judgment Value Or Reference Interval
It is recommended that each laboratory establish its own reference range of normal values.
Interpretation Of Test Results
The measurement of CHE in serum or plasma is only one of the indicators used by the clinician to make a diagnosis of the patient.
Limitations of the test method
Ascorbic acid ≤ 30 mg/dL, bilirubin ≤ 40 mg/dL, hemoglobin ≤ 500 mg/dL, celiac disease ≤ 500 mg/dL did not interfere with the determination.
Product Performance Index
Absorbance of reagent blank: wavelength 404 nm, optical diameter 1.0 cm, temperature 37°C, A0 ≤ 0.5.
Absorbance change rate of reagent blank: △A/min ≤ 0.01 at wavelength 404nm and optical diameter 1.0cm.
Analytical sensitivity: the kit tests 5000 U/L of the test substance, the absorbance change rate ΔA/min ≥0.02.
Linearity range: reagent linearity in the interval of 100~12500 U/L, linear correlation coefficient: r ≥ 0.990; in the interval of 100~4000 U/L, the absolute deviation of linearity should not exceed 400 U/L; in the interval of (4000- 12500 U/L, the relative deviation of linearity should not exceed ±10%.
Precision: repeatability CV≤ 5.0%; relative extreme difference between batches≤ 6.0%.
Accuracy: Relative deviation ≤ 10%.
- This product is for in vitro diagnosis only.
- Avoid contamination when using the reagent, the container used must be clean, and please take necessary precautions, do not swallow, and avoid contact with skin and mucous membrane.
- Please dispose of the measured samples and waste liquids in accordance with the relevant national and local laws and regulations.
- Do not mix R1 and R2 into a single reagent, or exchange reagents with different lot numbers.
- When changing the reagent lot number, please recalibrate.
- Deutsche Gesellschaft für Klinische Chemie, Proposal of Standard Methods for the determination of enzyme catalytic concentrations in serum and plasma. plasma at 37°C. II Cholinesterase (acylcholine acylhydydrolase). Eur.J.Clin.Chem., Clin. Biochem 30, 163 (1992).