D-Tryptophan CAS 153-94-6 (H-D-Trp-OH) Assay 98.5~101.0% Factory

Acidity
Take 1g of this product, add 50ml of water to dissolve, and measure according to law (General Rule 5.4). The pH value should be 5.4~6.4.
Transmittance of solution
take 0.5g of this product, add 2mol/L hydrochloric acid solution 20ml to dissolve, according to ultraviolet-visible spectrophotometry (General rule 0401), measure the transmittance at 430nm wavelength, not less than 95.0%.
Chloride
Take 0.25g of this product and check it according to law (General rule 0801). Compared with the control solution made of 0.02% of standard sodium chloride solution, it should not be more concentrated ().
Sulfate
Take l.0g of this product and check it according to law (General rule 0802). Compared with the control solution made of 0.02% of standard potassium sulfate solution, it should not be more concentrated ().
Ammonium Salt
Take 0.10g of this product and check it according to law (General rule 0808). Compared with the control solution made of 0.02% of standard ammonium chloride solution, it shall not be deeper ().
Other Amino Acids
Take 0.30g of this product, put it in a 20ml measuring flask, add 1 mol/L hydrochloric acid solution 1 ml and water to dissolve, dilute with water to the scale, shake well, as a test solution; take 1 ml accurately, put it in a 200ml measuring flask, dilute it to scale with water, shake well, and use it as a control solution. Take 10mg of tryptophan control and tyrosine control, and put it in the same 25ml measuring flask, 1 ml of 1 mol/L hydrochloric acid solution and an appropriate amount of water were added to dissolve the solution. The solution was diluted to the scale with water and then shaken to form a suitable solution for the system. According to the thin layer chromatography (General 0502) test, absorb the above three solutions each 2 μL, respectively, on the same silica gel G thin layer plate, with n-butanol-glacial acetic acid-water (3:1:1) to spread out, spread out, dry, spray with ninhydrin in acetone solution (1-50), heat at 80℃ until the * point appears, and view immediately. The control solution should show a clear spot, and the system applicable solution should show two completely separated spots. If the test solution shows impurity spots, the color should not be deeper (0.5%) than the main spot of the control solution.
Loss on Drying
Take this product, dry at 105℃ for 3 hours, loss of weight shall not exceed 0.2% (General rule 0831).
Residue on Ignition
Take 1.0g of this product and check it according to law (General rule 0841). The residue left shall not exceed 0.1%.
Iron Salt
Take this product 1.0g after burning and ashing, add hydrochloric acid (2ml) to the residue, dry it on a water bath, then add dilute hydrochloric acid (4ml), dissolve it in slight heat, add water (30ml) and ammonium persulfate (50mg), and check it according to law (General rule 0807), it should not be deeper (0.002%) than the control solution made of standard iron solution.
Heavy Metals
The residue left under the item of taking the ignition residue shall not contain more than 10 parts per million of heavy metal when examined by law (General Principles 0821, Law II).
Arsenic Salt
take 2.0g of this product, add 5ml of hydrochloric acid and 23ml of water to dissolve, check according to law (General rule 0822 first law), should comply with the provisions (0.0001%).
Bacterial Endotoxin
take this product, add human endotoxin test water, and heat to 80℃ to dissolve it, check according to law (General 1143), each lg of tryptophan containing endotoxin should be less than 50EU. (For injection)
Content Determination
Take this product about 0.15g, precision weighing, add anhydrous formic acid 3ml dissolved, add glacial acetic acid 50ml, according to the potential titration method (General rule 0701), with hydrochloric acid titration solution (0.1 mol/L) titration, and the results of the titration were corrected with a blank test. Each 1 ml of perchloric acid titration solution (0.1 mol/L) corresponds to 20.42mg of C11H12N2O2.