D-Histidine CAS 351-50-8 H-D-His-OH Assay 98.5~101.0% Factory

pH
take 1.0g of this product, add 50ml of water to dissolve, and measure it according to law (General rule 0631). The pH value should be 7.0~8.5.
Transmittance of Solution
Take 0.60g of this product, add water 20ml to dissolve, according to UV-visible spectrophotometry (General rule 0401), measure the transmittance at 430nm wavelength, not less than 98.0%.
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 1.0g 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 an appropriate amount of this product, add water to dissolve and dilute to make a solution containing about 10 mg per lml as a test solution; Take 1ml for precision measurement and put it in a 200ml measuring flask, dilute to scale with water, shake well, as a control solution; Take the appropriate amount of histidine reference and proline reference respectively, and place in the same measuring flask, water was added to dissolve and diluted to prepare a solution containing about 0.4mg each per 1ml as a system-suitable solution. According to the thin layer chromatography (General 0502) test, Draw 5 u1 of each of the above three solutions, respectively point on the same silica gel G thin layer plate, with N-propanol-concentrated ammonia solution (67:33) as the developing solvent, expand, dry, spray with ninhydrin in acetone solution (1-50), heat at 80°C until spots appear, and examine 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
Not more than 0.1% (General rule 0841).
Iron Salt
take 1.0g of this product and check it according to law (General rule 0807). Compared with the control solution made of 0.001% of standard iron solution, it shall not be deeper ().
Heavy metals
This product 1.0g, inspection according to law (General Principles 0821 The first law), containing heavy metals shall not exceed 10 parts per million.
Arsenic Salt
take 2.0g of this product, add 23ml of water to dissolve, add 5ml of hydrochloric acid, check according to law (General rule 0822 first law), should comply with the provisions (0.0001%).
Bacterial Endotoxin
Take this product, check according to law (General rule 1143), each lg histidine containing endotoxin should be less than 6.0EU. (For injection)
351-50-8 - Content determination
Take this product about 0.15g, precision weighing, add anhydrous formic acid 2ml to dissolve, add glacial acetic acid 50ml, according to the potential titration method (General rule 0701), with perchloric acid titration solution (0.1 mol/L) titration, and the results of the titration were corrected with a blank test. Each 1 ml perchloric acid titration solution (0.1 mol/ L) corresponds to 15.52mg of C6H9N302.