L-Isoleucine CAS 73-32-5 (H-Ile-OH) Assay 98.5~101.0% Factory High Quality

L-Isoleucine (H-Ile-OH) (CAS: 73-32-5) 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=4, 6mol/L HCl
State of Solution (Transmittance): 0.5g in 10ml of 1mol/L, HCl spectrophotometer, 430nm, 10nm cell thickness.
Chloride (Cl): 0.7g, A-1, ref: 0.40ml of 0.01mol/L HCl
Sulfate (SO4): 1.2g, (1), ref: 0.50ml of 0.005mol/L H2SO4
Iron (Fe): 1.5g, (1), ref: 1.5ml of Iron Std. (0.01mg/ml)
Heavy Metals (Pb): 2.0g, (1), dissolve by warming, ref: 2.0ml of Pb Std. (0.01mg/ml)
Arsenic (As2O3): 2.0g, (1), ref: 2.0ml of As2O3 Std.
Other Amino Acids: Test Sample: 50μg, B-6-a, control: L-Ile 0.25μg
Loss on Drying: at 105℃ for 3 hours.
Assay: Dried sample, 130mg, (3), 3ml of formic acid, 50ml of glacial acetic acid, 0.1mol/L HCLO4 1ml=13.117mg C6H13NO2
pH Test: 0.5g in 20ml of H2O 

L-Isoleucine (H-Ile-OH) (CAS: 73-32-5) USP35 Test Method
DEFINITION
Isoleucine contains NLT 98.5% and NMT 101.5% of L-Isoleucine (C6H13NO2), calculated on the dried basis.
IDENTIFICATION
A. INFRARED ABSORPTION <197K>
ASSAY
PROCEDURE
Sample: 130 mg of Isoleucine
Blank: Mix 3 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 3 mL of formic acid and 50mL of glacial acetic acid. Titrate with the Titrant. Perform the Blank determination.
Calculate the percentage of Isoleucine (C 6H13NO2) in the Sample taken:
Result = {[(VS-VB) x N x F]/W} x100
VS= Titrant volume consumed by the Sample (mL)
VB= Titrant volume consumed by the Blank (mL)
N= actual normality of the Titrant (mEq/mL)
F= equivalency factor, 131.2 mg/mEq
W= Sample weight (mg)
Acceptance criteria: 98.5%~101.5% on the dried basis
IMPURITIES
RESIDUEON IGNITION <281>: NMT 0.3%
CHLORIDE AND SULFATE, Chloride <221>
Standard solution: 0.50mL of 0.020 N hydrochloric acid
Sample: 0.73g of Isoleucine
Acceptance criteria: NMT 0.05%
CHLORIDE AND SULFATE, Sulfate <221>
Standard solution: 0.10mL of 0.020 N sulfuric acid
Sample: 0.33g of Isoleucine
Acceptance criteria: NMT 0.03%
IRON <241>: NMT 30ppm
Delete the following:
HEAVY METALS, Method I <231>: NMT 15ppm
RELATED COMPOUNDS
System suitability solution: 0.4mg/mL each of USP L-Isoleucine RS and USP L-Valine RS in 0.1 N hydrochloric acid
Standard solution: 0.05mg/mL of USP L-Isoleucine RS in 0.1 N hydrochloric acid. [NOTE-This solution has a concentration equivalent to 0.5% of that of the Sample solution.]
Sample solution: 10mg/mL of Isoleucine in 0.1 N hydrochloric acid
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: Butyl alcohol, glacial acetic acid, and water (3:1:1)
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.
After air-drying the plate, 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.
Individual impurities: NMT 0.5%
Total impurities: NMT 2.0%
SPECIFIC TESTS
OPTICAL ROTATION, Specific Rotation <781S>
Sample solution: 40 mg/mL in 6 N hydrochloric acid
Acceptance criteria: +38.9° to +41.8°
PH <791>
Sample solution: 10 mg/mL solution
Acceptance criteria: 5.5~7.0
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-Isoleucine RS
USP L-Valine RS