L-Valine CAS 72-18-4 (H-Val-OH) Assay 98.5~101.0% Factory High Quality

L-Valine (H-Val-OH) (CAS: 72-18-4) AJI 97 Test Method
Identification: Compare the infrared absorption spectrum of the sample with that of the standard by potassium bromide disc method.
Specific Rotation [α]20/D: Dried Sample, C=8, 6mol/L HCl
State of Solution (Transmittance): 0.5g in 20ml of H2O, spectrophotometer, 430nm, 10mm cell thickness.
Chloride (Cl): 0.7g, A-1, ref: 0.40ml of 0.01mol/L HCl
Ammonium (NH4): B-2
Sulfate (SO4): 1.2g, (1), ref: 0.50ml of 0.005mol/L H2SO4
Iron (Fe): 1.5g, (2), ref: 1.5ml of Iron Std. (0.01mg/ml)
Heavy Metals (Pb): 2.0g, (2), ref: 2.0ml of Pb Std. (0.01mg/ml)
Arsenic (As2O3): 2.0g, (2), ref: 2.0ml of As2O3 Std.
Other Amino Acids: Dilute ammonia R2 Test Sample: 50μg, F-6-a, control: L-Tyr 0.25μg
Loss on Drying: at 105℃ for 3 hours.
Residue on Ignition (Sulfated): AJI Test 13
Assay: Dried sample, 120mg, (1), 3ml of formic acid, 50ml of glacial acetic acid, 0.1mol/L HCLO4 1ml=11.715mg C5H11NO2
pH Test: 1.0g in 20ml of H2O

L-Valine (H-Val-OH) (CAS: 72-18-4) JP16 Test Method
L-Valine, when dried, contains not less than 98.5% of C5H11NO2.
Description L-Valine occurs as white crystals or crystalline powder. It is odorless or has a faint characteristic odor, and has a slightly sweet taste, which becomes bitter.
It is freely soluble in formic acid, soluble in water, and practically insoluble in ethanol (95).
It dissolves in dilute hydrochloric acid.
Identification Determine the infrared absorption spectrum of L-Valine, previously dried, as directed in the potassium bromide disk method under Infrared Spectrophotometry <2.25>, and compare the spectrum with the Reference Spectrum: both spectra exhibit similar intensities of absorption at the same wave numbers.
Optical rotation <2.49> [a]20D: +26.5°~+29.0° (after drying, 2 g, 6 mol/L hydrochloric acid TS, 25 mL, 100 mm).
pH <2.54> Dissolve 0.5 g of L-Valine in 20 mL of water: the pH of this solution is between 5.5 and 6.5.
Purity (1) Clarity and color of solution Dissolve 0.5 g of L-Valine in 20 mL of water: the solution is clear and colorless.
(2) Chloride <1.03>-Perform the test with 0.5 g of L-Valine. Prepare the control solution with 0.30 mL of 0.01mol/L hydrochloric acid VS (not more than 0.021%).
(3) Sulfate <1.14>-Perform the test with 0.6 g of L-Valine. Prepare the control solution with 0.35 mL of 0.005mol/L sulfuric acid VS (not more than 0.028%).
(4) Ammonium <1.02>-Perform the test with 0.25 g of L-Valine. Prepare the control solution with 5.0 mL of Standard Ammonium Solution (not more than 0.02%).
(5) Heavy metals <1.07>-Proceed with 1.0 g of L-Valine according to Method 1, and perform the test. Prepare the control solution with 2.0 mL of Standard Lead Solution (not more than 20 ppm).
(6) Arsenic <1.11>-Proceed with 1.0g of L-Valine, prepare the test solution according to Method 2, and performthe test (not more than 2 ppm).
(7) Related substances-Dissolve 0.10 g of L-Valine in 25mL of water, and use this solution as the sample solution. Pipet 1 mL of the sample solution, and add water to make exactly 50 mL. Pipet 5 mL of this solution, add water to make exactly 20 mL, and use this solution as the standard solution. Perform the test with these solutions as directed under Thin-layer Chromatography <2.03>. Spot 5mL each of the sample solution and standard solution on a plate of silica gel for thin-layer chromatography. Develop the plate with amixture of 1-butanol, water and acetic acid (100) (3:1:1) to adistance of about 10 cm, and dry the plate at 80℃ for 30 minutes. Spray evenly a solution of ninhydrin in acetone (1 in 50) on the plate, and heat at 80℃ for 5 minutes: the spots other than the principal spot from the sample solution are not more intense than the spot from the standard solution.
Loss on drying <2.41> Not more than 0.30% (1 g, 105℃,3 hours).
Residue on ignition <2.44> Not more than 0.1% (1 g).
Assay Weigh accurately about 0.12 g of L-Valine, previously dried, and dissolve in 3 mL of formic acid, add 50 mL of acetic acid (100), and titrate <2.50> with 0.1 mol/L perchloric acid VS (potentiometric titration). Perform a blank determination, and make any necessary correction.
Each mL of 0.1 mol/L perchloric acid VS＝11.72 mg of C5H11NO2
Containers and storage Containers-Tight containers.