L-(-)-Tyrosine CAS 60-18-4 (H-Tyr-OH) Assay 98.5~101.5% Factory High Quality

L-(-)-Tyrosine (H-Tyr-OH) (CAS: 60-18-4) 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=5, 1mol/L HCl
State of Solution (Transmittance): 0.5g in 10ml of 1mol/L HCl, 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, 180mg, (1), 6ml of formic acid, 50ml of glacial acetic acid, 0.1mol/L HCLO4 1ml=18.119mg C9H11NO3
pH Test: 0.02g in 100ml saturated aqueous solution

L-(-)-Tyrosine (H-Tyr-OH) (CAS: 60-18-4) USP35 Test Method
DEFINITION
Tyrosine contains NLT 98.5% and NMT 101.5% of L-Tyrosine (C9H11NO3), calculated on the dried basis.
IDENTIFICATION
A. INFRARED ABSORPTION <197K>
ASSAY
PROCEDURE
Sample: 180 mg of Tyrosine
Blank: Mix 6 mL of formic acid and 50 mL of glacial acetic acid.
Titrimetric system
(See Titrimetry <541>)
Mode: Direct titration
Titrant: 0.1 N perchloric acid VS
Endpoint detection: Potentiometric
Analysis: Dissolve the Sample in 6 mL of formic acid and 50mL of glacial acetic acid, and titrate with the Titrant. Perform the Blank determination.
Calculate the percentage of tyrosine (C9H11NO3) in the Sample taken:
Result = {[(VS-VB) x N x F]/W} x100
VS= volume of Titrant consumed by the Sample (mL)
VB= volume of Titrant consumed by the Blank (mL)
N= actual normality of the Titrant (mEq/mL)
F= equivalency factor, 181.2 mg/mEq
W= Sample weight (mg)
Acceptance criteria: 98.5%~101.5% on the dried basis
IMPURITIES
RESIDUEON IGNITION <281>: NMT 0.4%
CHLORIDE AND SULFATE, Chloride <221>
Standard solution: 0.20mL of 0.020 N hydrochloric acid
Sample: 0.35 g of Tyrosine. [NOTE-If necessary, dissolve the Sample by heating to near boiling and adding 1 mL of nitric acid.]
Acceptance criteria: NMT 0.04%
CHLORIDE AND SULFATE, Sulfate <221>
Standard solution: 0.50mL of 0.020 N sulfuric acid
Sample: 1.2 g of Tyrosine. [NOTE-If necessary, dissolve the Sample by adding 6 mL of diluted hydrochloric acid.]
Acceptance criteria: NMT 0.04%
IRON <241>: NMT 30ppm [NOTE-If necessary, use 2 mL of hydrochloric acid to dissolve the Sample.]
HEAVY METALS, Method I <231>: NMT 15ppm
RELATED COMPOUNDS
Diluted ammonia solution: Dilute 16 mL of concentrated ammonia with water to 100 mL.
System suitability solution: Dissolve 10 mg of USP L-Tyrosine RS and 10 mg of USP L-Phenylalanine RS in 1 mL of Diluted ammonia solution, and dilute with water to 25.0 mL.
Standard solution: In a suitable flask, dissolve a quantity of USP L-Tyrosine RS in 1 mL of Diluted ammonia solution. Dilute with water to volume to obtain a solution of 0.05mg/mL. [NOTE-This solution has a concentration equivalent to 0.5% of that of the Sample solution.]
Sample solution: Transfer 0.1 g of Tyrosine into a 10-mL volumetric flask, add sufficient Diluted ammonia solution to dissolve, and dilute with water to volume.
Chromatographic system (See Chromatography <621>, Thin-Layer Chromatography.)
Mode: TLC
Adsorbent: 0.25-mm layer of chromatographic silica gel mixture
Application volume: 5μL
Developing solvent system: Isopropyl alcohol and ammonium hydroxide (7:3)
Spray reagent: 2 mg/mL of ninhydrin in a mixture of butyl alcohol and 2N acetic acid (95:5)
System suitability
Suitability requirements: The chromatogram of the System suitability solution exhibits two clearly separated spots.
Analysis
Samples: System suitability solution, Standard solution, and Sample solution.
Dry the plate between 100° and 105° until the ammonia disappears completely. Spray with Spray reagent, and heat between 100° and 105° for 15 min. Examine the plate under white light.
Acceptance criteria: Any secondary spot of the Sample solution is not larger or more intense than the principal spot of the Standard solution.
Any Individual impurities: NMT 0.5%
Total impurities: NMT 2.0%
SPECIFIC TESTS
OPTICAL ROTATION, Specific Rotation <781S>
Sample solution: 50 mg/mL in 1 N hydrochloric acid
Acceptance criteria: -9.8° to -11.2°
LOSSON ON DRYING <731>: Dry a sample at 105℃ for 3 h: it loses NMT 0.3% of its weight.
ADDITIONAL REQUIREMENTS
PACKAGING AND STORAGE: Preserve in well-closed containers.
USP REFERENCE STANDARDS <11>
USP L-Phenylalanine RS
USP L-Tyrosine RS