Taurine CAS 107-35-7 Assay 99.0~101.0% Factory High Quality

Taurine (CAS: 107-35-7) JP Test Method
Taurine, when dried, contains not less than 99.0% and not more than 101.0% of C2H7NO3S.
Description Taurine occurs as colorless or white crystals, or a white crystalline powder.
It is soluble in water, and practically insoluble in ethanol (99.5).
The pH of a solution prepared by dissolving 1.0 g of Taurine in 20 mL of freshly boiled and cooled water is between 4.1 and 5.6.
Identification Determine the infrared absorption spectrum of Taurine 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.
Purity (1) Clarity and color of solution-A solution obtained by dissolving 1.0 g of Taurine in 20 mL of water is clear and colorless.
(2) Chloride <1.03>-Perform the test with 1.0 g of Taurine. Prepare the control solution with 0.30 mL of 0.01mol/L hydrochloric acid VS (not more than 0.011%).
(3) Sulfate <1.14>-Perform the test with 2.0 g of Taurine. Prepare the control solution with 0.40 mL of 0.005 mol/L sulfuric acid VS (not more than 0.010%).
(4) Ammonium <1.02>-Perform the test with 0.25 g of Taurine. Prepare the control solution with 5.0 mL of Standard Ammonium Solution (not more than 0.02%).
(5) Heavy metals <1.07>-Proceed with 2.0 g of Taurine according to Method 1, and perform the test. Prepare the control solution with 2.0 mL of Standard Lead Solution (not more than 10 ppm).
(6) Iron <1.10>-Prepare the test solution with 2.0 g of Taurine according to Method 1, and perform the test according to Method A. Prepare the control solution with 2.0 mL of Standard Iron Solution (not more than 10 ppm).
(7) Related substances-Dissolve 1.0 g of Taurine in 50 mL 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 1 mL of this solution, add water to make exactly 10 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 a mixture of water, ethanol (99.5), 1-butanol and acetic acid (100) (150:150:100:1) to a distance of about 10 cm, and air-dry the plate. Spray evenly ninhydrin-butanol TS on the plate, and heat at 105℃ for 5 minutes: the spot other than the principle spot with the sample solution is not more than one spot, and it is not more intense than the spot with the standard solution.
Loss on drying <2.41> Not more than 0.20% (1 g, 105℃, 2 hours).
Residue on ignition <2.44>Not more than 0.1% (1 g).
Assay Weigh accurately about 0.2 g of Taurine, previously dried, dissolve in 50 mL of water, add 5 mL of formaldehyde solution, and titrate<2.50>with 0.1 mol/L sodium hydroxide VS (potentiometric titration). Perform a blank determination in the same manner, and make any necessary correction.
Each mL of 0.1 mol/L sodium hydroxide VS ＝12.52 mg of C2H7NO3S
Containers and storageContainers-Well-closed containers.

Taurine (CAS: 107-35-7) USP Test Method
DEFINITION
Taurine contains NLT 98.5% and NMT 101.5% of taurine (C2H7NO3S), calculated on the dried basis.
IDENTIFICATION
• A. INFRARED ABSORPTION <197K>
ASSAY
• NITROGEN DETERMINATION, Method II <461>
Analysis: Proceed as directed in the chapter. Each mL of 0.01 N sulfuric acid is equivalent to 1.25 mg of C2H7NO3S.
Acceptance criteria: 98.5%-101.5% on the dried basis
IMPURITIES
• RESIDUE ON IGNITION <281>: NMT 0.3%
• CHLORIDE AND SULFATE, Chloride <221>
Standard: 0.50 mL of 0.020 N hydrochloric acid
Sample: 0.7 g of Taurine
Acceptance criteria: NMT 0.05%
• CHLORIDE AND SULFATE, Sulfate <221>
Standard: 0.25 mL of 0.020 N sulfuric acid
Sample: 0.8 g of Taurine
Acceptance criteria: NMT 0.03%
• IRON <241>: NMT 30 ppm
• HEAVY METALS, Method I <231>: NMT 15 ppm
• RELATED COMPOUNDS
Standard solution: 0.05 mg/mL of USP Taurine RS in water an equivalent concentration of about 0.5% of the Sample solution
Sample solution: 10 mg/mL of Taurine in water
Chromatographic system
(See Chromatography <621>, Thin-Layer Chromatography.)
Mode: TLC
Adsorbent: 0.25-mm layer of chromatographic silica gel mixture
Application volume: 5 µL
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 2 N acetic acid (95:5)
Analysis: Dry the plate at 80° for 30 min. Spray the plate with Spray reagent, and heat at 80° for about 10 min. Examine the plate under white light. [NOTE-The RF value for the taurine spots should be about 0.2.]
Acceptance criteria: No secondary spot of the Sample solution is larger or more intense than the principal spot of the Standard solution.
Individual impurities: NMT 0.5%
SPECIFIC TESTS
• LOSS 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 Taurine RS