What is the purity testing method of EDTA Tripotassium?
Tripotassium ethylenediaminetetraacetate is called EDTA-3K for short. Because of its anticoagulant performance, it is often used as an anticoagulant in blood collection vessels, and is favored by some reagent manufacturers. But at the same time, due to the expansion of demand, there are more and more manufacturers producing tri potassium EDTA, the quality becomes uneven, and many low-quality products are also included.
What are the representative characteristics of "inferior" products? The main problems are unstable performance, low purity and appearance defects. How to identify these "inferior" products? In fact, PH value, clarity, solubility, purity and impurities are the key factors that determine the performance of EDTA. Special attention should be paid to these indicators, which can be detected if necessary, so as to avoid buying inferior products with poor performance. So, what is the purity detection method of EDTA? Next, I would like to give you a detailed introduction.
1. Purity test
The detection method of tri potassium ethylenediaminetetraacetate is the same as that of di potassium ethylenediaminetetraacetate. The main method is to weigh 0.1g tri potassium ethylenediaminetetraacetate sample, which can be accurate to 0.0001g under special circumstances. Add 70mL of water and 10mL of ammonia ammonium chloride buffer solution with pH value of about 10. After the sample is fully dissolved, add 5 drops of chrome black T indicator, 5g/L, and titrate with zinc chloride standard titration solution until the solution turns red purple [c (ZnCL2)=0.025mol/L].
2. PH value detection
Weigh 5g of test EDTA potassium sample, dissolve it in 100ml of pure water, stir for about 5min at room temperature, and test the PH value. The pH value of Desheng's EDTA potassium is 7.3 ± 1 (5% aqueous solution, g/ml).
3. Clarity test
Weigh 20g of EDTA tri potassium test sample, dissolve it in 100ml of pure water solution, stir for 5-10 minutes at room temperature, and compare the prepared solution with colorless transparent liquid to see if it is clear.
4. Solubility test
Weigh 60.0g of EDTA tri potassium sample to be tested, dissolve it in 100ml pure water, stir for 5-10 minutes at 25 ℃ at room temperature, carefully observe the dissolution, and see if the water solubility is greater than or equal to 60%.
5. Impurity detection
Place 0.22 filter membrane in the detection apparatus, pour the EDTA tripotassium solution into the filter, and observe whether there are impurities or excessive impurities on the filter membrane. If there are many impurities, it is recommended not to use it.
The above five detection methods are used to judge whether the quality of EDTA tripotassium is up to the standard. The key is the purity, which is up to 99% or more, and will not affect the detection experiment, so you can add it into the test tube with confidence.
Desheng Biochemical has been committed to developing the research, development, production and sales of additives for blood collection vessels. As one of the main products, tri potassium ethylenediaminetetraacetate is not only of high purity, but also indicators in all aspects are formulated by R&D personnel according to the testing standards, with strict requirements and precise control. If you have the demand for EDTA, please click the website for consultation and purchase!