L-Threonine

EP6

AJI92

USP40

Description

White or almost white,crystalline powder or colourless crystals

White crystals or crystalline powder

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Solubility

Soluble in water, practically insoluble in alcohol.

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Identification test (A,B）

Conforms

Conforms

Conforms

Appearance of solution

Solution S is clear and colourless

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Assay

99.0-101.0%

99.0%～100.5%

98.5%～101.5%

pH

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5.2~6.2

5.0~6.5

Transmittance

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≥98.0%

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Loss on drying

≤0.5%

≤0.20%

≤0.2%

Residue on ignition

≤0.1%

≤0.10%

≤0. 4%

Ninhydrin-positive substances  (TLC)

Conforms

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Chloride

≤200ppm

≤0.020%

≤0.05%

Heavy Metals

≤10ppm

≤10ppm

≤15ppm

Iron

≤10ppm

≤10ppm

≤0.003%

Sulfate

≤300ppm

≤0.020%

≤0.03%

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

Conform

Pyrongen

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Conforms

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Specific Rotation

-27.6°～-29.0°

-27.6°~ -29.0°

-26.7°~-29.1°