L-Methionine

EP6

AJI92

USP40

Description

A white or almost white, crystalline powder or colourless crystals

White crystals or crystalline powder

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Solubility

Soluble in water,very slightly soluble in alcohol

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Identification test (A,B）

Conforms

Conforms

Conforms

Appearance of solution

Clarity of solution:2.5% water solution should be clear

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Colour of solution:2.5% water solution should be colourless

Assay

99.0%-101.0%

98.5%～101.5%

98.5%～101.5%

pH

5.5～6.5

5.6~6.1

5.6~6.1

Transmittance

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≥98.0%

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Specific optical rotation

+22.5°～ +24.0°

+23.0° ～ +25.0°

+22.4º～+24.7º

Loss on drying

≤0.5%

≤0.20%

≤0.3%

Residue on ignition

≤0.1%

≤0.10%

≤0.4%

Ninhydrin-positive Substances (TLC)

Conforms

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Bacterial endotoxin

＜25EU/g

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Chloride

≤200ppm

≤0.020%

≤0.05%

Heavy Metals

≤10ppm

≤10ppm

≤0.0015%

Iron

≤10ppm

≤10ppm

≤0.003%

Sulfate

≤300ppm

≤0.020%

≤0.03%

Endotoxin

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Arsenic

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≤1ppm

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Ammonium

≤200ppm

≤0.02%

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Other amino acids

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Conforms

Conforms

Pyrongen

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Conforms

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Hydrolyzable substances

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