-
Categories
-
Pharmaceutical Intermediates
-
Active Pharmaceutical Ingredients
-
Food Additives
- Industrial Coatings
- Agrochemicals
- Dyes and Pigments
- Surfactant
- Flavors and Fragrances
- Chemical Reagents
- Catalyst and Auxiliary
- Natural Products
- Inorganic Chemistry
-
Organic Chemistry
-
Biochemical Engineering
- Analytical Chemistry
- Cosmetic Ingredient
-
Pharmaceutical Intermediates
Promotion
ECHEMI Mall
Wholesale
Weekly Price
Exhibition
News
-
Trade Service
7.
(1) Qualitative target compound
Qualitatively based on the retention time of each component of the standard material and comparison with the standard mass spectrum
(2) Quantitative calculation
1.
The relative response factor RRF i of the target in the ith point of the standard series is calculated according to formula (1)
In the formula, A i -the response value of the quantitative ion of the ith target in the standard series;
A ISi -the response value of the internal standard quantitative ion corresponding to the i-th target in the standard series;
p IS —the mass concentration of the internal standard in the standard series;
p i —the mass concentration of the target at the i-th point in the standard series
The average relative response factor of the target is calculated according to formula (2)
2.
When the target is calibrated with the average response factor, the mass concentration of the target in the sample p ex (ug/L) is calculated according to formula (3)
Where A x -the response value of the target quantitative ion;
A IS —The response value of the internal standard quantitative ion corresponding to the target;
p IS —the mass concentration of the internal standard substance in the standard series, ug/L;
—The average relative response factor of the target
8.
(1) Analyze at least one blank sample, parallel sample and leaching solution spiked sample for each batch of samples to ensure the accuracy of the analysis process.
(2) The configuration of the standard series should be at least 5 points, and the configuration mass concentration range should cover the mass concentration of the sample to be tested
(3) Before the analysis of each batch of samples or within 24h, it is necessary to check the performance of the instrument, measure the calibration confirmation standard sample ( decafluorotriphenylphosphine ) and the blank sample
Nine, matters needing attention
(1) The two isomers of 1,4-dinitrobenzene and 1,3-dinitrobenzene cannot be separated on a 5% diphenyl-dimethyl polysiloxane column, if any For separation, it is recommended to use 35% phenyl-methyl polysiloxane or other chromatographic column analysis that can separate its baseline
(2) Analysis phthalate When substances, the experiment should be noted that a blank background contamination, avoiding contact with plastic products, special care to avoid contamination from the solvent
(3) For complex matrix samples, it is recommended to perform purification before entering the instrument for testing
(4) The detection limit of the single quadrupole GC/MS for the determination of benzo(a)pyrene is affected by the performance of the detector, and may not meet the limit requirements in GC5085.
3-2007.
Liquid chromatography-fluorescence detection can be used The instrument method detects benzo(a)pyrene
.
When using this method for analysis, care should be taken to transfer the sample solution of the dichloromethane system to the acetonitrile system, and then inject it into the liquid chromatograph for analysis
.
When determining benzo(a)pyrene by GC-MS, you can consider increasing the voltage of the electron multiplier tube to improve the signal response.
You can also increase the mass concentration range of the monitored sample by increasing the sampling volume or the concentration multiple, so as to achieve the "Hazardous Waste Identification" Standard leaching toxicity identification" (GB5085.
3-2007) in the standard limit requirements of benzo(a)pyrene
.