Selling unit: per 100ml
- Common name: N-acetyl-β-D-aminoglucosidase (NAG) assay kit (method)
- English name: NAG Reagent Kit (MPT Method)
3:1, 4:1, 5:1, common ratio 4:1, other ratios need to be customized
This reagent is used to determine the amount of NAG in urine.
NAG is a macromolecular glycoprotein and an important lysosomal hydrolase that is widely present in the human body. It is not filtered by the glomerulus in the urinary circulation, and when the renal parenchyma is damaged, the urinary NAG is increased, which is considered to be a more sensitive indicator of the early stage of renal damage; NAG can be used for the auxiliary diagnosis of renal tumors. Urinary NAG is reported to be significantly elevated in renal malignancies, and its level is related to the size of the tumor and the degree of renal parenchymal damage. In renal transplant patients, urinary NAG measurement can detect rejection at an early stage, generally 1 to 3 days before the appearance of various clinical indications that have elevated urinary NAG. In diabetic nephropathy, urinary NAG is significantly elevated.
NAG catalyzes the reaction of the substrate MPT-NAG to form N-acetyl-β-D-glucosaminide and MPT. MPT increases in absorbance at 340 nm, and the rate of increase in absorbance is determined by the concentration of NAG. The NAG content in the sample can be detected according to the standard curve.
Reagent components included in the product.
*Components are not interchangeable in kits with different lot numbers.
*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.
Fresh urine samples.
- 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.
The use of matching calibrators is 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
Bilirubin ≤ 40 mg/dL, celiac ≤ 500 mg/dL, hemoglobin ≤ 200 mg/dL, and vitamin C ≤ 20 mg/dL had no effect on the test results.
Limitations Of The Test Method.
The determination of NAG in human serum is only one of the indicators used by the clinician to make a diagnosis of the patient. The clinician must also make a comprehensive judgment based on the patient’s physical symptoms, medical history, and other diagnostic items and diagnostic tools.
Product Performance Index
Absorbance of reagent blank: wavelength 340 nm, optical diameter 1.0 cm, temperature 37°C, A0 ≤ 0.25.
Absorbance change rate of reagent blank: △A/min ≤ 0.02 at wavelength 340 nm and optical diameter 1.0 cm.
Analytical sensitivity: The kit tests 100 U/L of the test substance with an absorbance change rate ΔA/min ≥ 0.02.
Linearity range: test serum samples, reagent linearity in the range of 2 to 200 U/L, linear correlation coefficient|r| should not be less than 0.990; in the interval of 2 to 20 U/L, the absolute deviation of linearity should not exceed 2 U/L; in the interval of (20 to 200 U/L, the relative deviation of linearity should not exceed ±10%.
Precision: repeatability CV ≤ 5%; relative extreme difference between batches ≤ 10%.
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.
- Please dispose of the measured samples and waste liquids according to the relevant national and local laws and regulations.
- When changing the reagent lot number, the calibration should be re-calibrated.
- Jean-François Naud and Martine Leblanc, Biomark Insights. 2008, 3:115-125.