GBZ/T 304-2018Determination of aluminum in urine -- Graphic furnace atomic absorption spectrometry method (English PDF)

Foreword

This standard is formulated in accordance with the Law of the People's Republic this standard was drafted in accordance with the rules given in GB/T 1.1-2009.

This standard is mainly drafted by. Guangdong Provincial Occupational Disease Prevention and Treatment Institute, Guangzhou Occupational Disease Prevention and Treatment Institute, Shenzhen Occupational Disease Prevention and Treatment Institute, Qingyuan City Center for Disease Control and Prevention, Guangdong Pharmaceutical University.

1 Scope

This standard specifies graphite furnace atomic absorption spectrometry for the determination of aluminum in urine.

This standard applies to the determination of aluminum in the urine of occupational contact personnel.

2 Normative references

The following documents are indispensable for the application of this document. For dated references, only the dated version applies to this document.

For undated references, the latest edition (including all amendments) applies to this document.

General rules for biological monitoring of GBZ/T 295 occupational population

3 Principle

Urine sample (hereinafter referred to as urine sample) plus diluent treatment, direct injection, at 339.3nm wavelength, using graphite furnace atomic absorption spectrometry the method measures the concentration of aluminum.

4 Instruments

4.1 Graphite furnace atomic absorption spectrometer with background correction device and aluminum hollow cathode lamp.

4.2 Thermostatic platform pyrolytic graphite tube or pyrolytic coated graphite tube.

4.3 stoppered polyethylene plastic bottle, 100mL.

4.4 stoppered polyethylene plastic tube, 5mL, 2mL.

4.5 urine hydrometer.

4.6 Micropipettes, 1000L,.200L, 50L.

4.7 Glass instruments and plastic utensils are soaked in 50% nitric acid for more than 24 hours, rinsed, and dried for use.

5 Reagent

5.1 Experimental water. Distilled water in deionized water or full glass distiller.

5.2 Nitric acid, rho20=1.42 g/mL, excellent grade pure.

5.3 Nitric acid solution, 1% (V/V).

5.4 Polyethylene glycol octyl phenyl ether (TritonX-100), excellent grade.

5.5 Thinner. Add 0.10 mL TritonX-100 and 0.50 mL HNO3 to 100 mL of deionized water and mix.

5.6 Aluminum standard solution. Nationally recognized standard solution.

5.7 Aluminum Standard Stock Solution and Aluminum Standard Application Solution. Accurately absorb 10.0 mL of aluminum standard solution (100.0g/mL) and place it in a 100 mL volumetric flask.

Make up to the mark with nitric acid solution, this is the standard stock solution of aluminum, the concentration is 10.0g/mL, dilute the aluminum standard stock solution with diluent when it is used.

0.50 g/mL aluminum standard application solution.

6 Sample collection, transportation and storage

According to the requirements of GBZ/T 295, the polyethylene plastic bottle is used to collect the urine sample of the aluminum contact worker, and after mixing, the urine specific gravity is measured as soon as possible.

After adding 1 mL of nitric acid to a 100 mL urine sample, it should be transported as soon as possible at room temperature, and stored for at least 7 days at 2 °C to 6 °C.

7 Analysis steps

8 Calculation

8.1 Calculate the concentration correction factor (k) for the urine sample converted to the standard specific gravity (1.020) according to formula (1).

000.1

000.1020.1

Measured specific gravity k ...(1)

8.2 Calculate the concentration of aluminum in urine according to formula (2).

kFcc xx= 0 ...(2)

In the formula.

C -- the concentration of aluminum in the urine, in micrograms per liter (g/L);

C0--the concentration of aluminum found from the standard curve in micrograms per liter (g/L);

F -- dilution ratio of urine sample;

k -- The urine sample is converted to the concentration correction factor at the standard specific gravity (1.020).

9 Description

9.1 The detection limit of this method is 2.50g/L, the lower limit of quantification is 8.25g/L (5 times diluted with urine sample), and the measurement range is 8.25µg/L~ 250.0 g/L, inter-assay precision of 3.9% ~ 8.2% (urinary aluminum spiked concentration of 25.0 g/L ~.200.0 g/L, n = 6); spiked recovery it is 87.6% to 104.9% (the concentration of urinary aluminum is 25.0 g/L to.200.0 g/L, n=6).

9.2 This method should preferably use a thermostatic platform pyrolytic graphite tube or a pyrolytic coated graphite tube. The operator should be based on the performance of the instrument and graphite tube used.

Adjust the instrument to its optimum working condition.

9.3 The experimental process should be strictly protected against contamination. The equipment used in the experiment was soaked with 50% HNO3 overnight and cleaned, if the aluminum blank of the experimental apparatus Still higher, it requires 6g/L of disodium edetate (Na2EDTA) solution; powder gloves are prohibited.

9.4 Using 0.10% TritonX-100 0.50% HNO3 (V/V) as a diluent, can improve the precision of the method, the diluent should be used immediately;

When the urine sample is diluted at least 5 times, the precision is better; the aluminum content of the blank urine sample should not exceed 12.5 g/L.

9.5 When the aluminum concentration is 206.8g/L,.2000g/L Mg2, Na, K, Ca2, Zn2, Cd2, Pb2, Cu2, Cl-,.200g/L Ni2, Mn 2. Cr3 does not interfere with the measurement.