Urine delta-amino-gamma-ketovaleric acid

The increase in δ-ALA activity is a specific reaction to lead and is clinically used to identify lead poisoning and iron deficiency. In the urine, δ-aminolevulinic acid (δ-ALA) is condensed with ethyl acetoacetate to form a pyrrole compound, which is extracted with ethyl acetate and then reacted with p-dimethylaminobenzaldehyde to form a red compound, which is quantified according to color depth and color. . Basic Information Specialist classification: urinary examination classification: urine / kidney function test Applicable gender: whether men and women apply fasting: fasting Tips: If the urine sample cannot be measured immediately, it should be stored in the refrigerator. The boiling time should be from the colorimetric tube into the water bath, the water is boiled again, and the calculation time starts, not less than 12 minutes. Normal value 0 to 45.8 μmol/24 h (0 to 6 mg/24 h). Clinical significance Elevation is seen in acute lead poisoning. High results may be diseases: precautions for lead poisoning (1) Ethyl acetate and ethyl acetoacetate are preferred in the near future. If ethyl acetoacetate turns yellow, it cannot be used. The color developer should be prepared before use. (2) If the urine sample cannot be measured immediately, it should be stored in the refrigerator. (3) The boiling time should be from the colorimetric tube into the water bath, the water is boiled again, and the calculation time starts, not less than 12 minutes. (4) When the δ-ALA content in urine is high, the sampling amount can be reduced. It can be stabilized for 60 minutes after coloring. Inspection process (1) Sampling, transportation and storage: Collect 50 ml of urine samples from lead workers in plastic bottles, measure the specific gravity as soon as possible and bring them back to the laboratory (transport in summer, preferably in cold storage), and store them in the refrigerator (4 °C) for 2 weeks. (2) Sample treatment: Take 2 10 ml plug colorimetric tubes, add 1 ml of urine sample, 1 ml of water, 2 ml of buffer, and mix. One of the tubes was a sample tube, and 0.4 ml of ethyl acetoacetate was added; the other tube was a blank tube, and 0.4 ml of a buffer solution was added, and the mixture was thoroughly mixed. (3) Drawing of standard curve: Take 6 10ml plug colorimetric tubes, add 0.00, 0.10, 0.30, 0.50, 0.70, 1.00ml δ-ALA standard solution, and add water to 2.0ml (0.0,1.0,3.0) , 5.0, 7.0, 10.0 μg δ-ALA). Add 2 ml of buffer solution, 0.4 ml of ethyl acetoacetate to each tube, mix well; heat in a boiling water bath for 12 min, take out and cool to room temperature, add 4 ml of ethyl acetate each, shake it 100 times, centrifuge for 5 min, and let stand. Layer; each 2ml ethyl acetate extract in another 6 10ml plug colorimetric tube, add 2ml each color developer, mix, let stand for 10min, at 554nm, use 10mm absorption pool, take the zero tube as the reference The absorbance is measured. The standard curve is drawn by taking the absorbance value as the ordinate and the δ-ALA content as the abscissa. (4) Sample measurement: The sample solution after treatment is drawn according to a standard curve, and the absorbance is measured. The absorbance of the sample tube was subtracted from the absorbance of the urine blank tube, and the mass of the δ-ALA in the sample tube was found from the standard curve. Not suitable for the crowd Generally no taboos. Adverse reactions and risks No.