Alpha Lipoic Acid 1077-28-7

ITEMS

STANDARD

RESULT

Appearance

Yellow crystalline powder

Conforms

Identification (HPLC)

       Meets the requirements

Conforms

Melting point

60~62°C

61.8°C

Solubility (1N NaOH)

Clear and pale yellow

Conforms

Residue on ignition

≤0.10%

< 0.03%

Heavy metals

≤10 ppm

<10 ppm

Chloride

≤0.10%

< 0.07%

Loss on drying (vacuum 40°C 3hr)

≤0.20%

0.04%

Assay (by HPLC,USP method)

99.0~101.0%

99.36%

Specific optical rotation

-1°~+1°

Conforms

Related substance(by HPLC)

Single impurity   ≤0.10%

0.05%

6,8-Epitrithiooctanoic acid ≤0.10%

0.01%

Total impurities     ≤0.50%

0.07%

Polymers (by TLC)

≤2.0%

<2.0%

Residual solvents(by GC)

Toluene     ≤30ppm

<20ppm

Ethyl acetate ≤250ppm

Undetected

Cyclohexane ≤0.20%

0.07%

Microbiology

Total aerobic counts ≤1000CFU/g

<100CFU/g

Mould & yeast ≤100CFU/g

<10CFU/g

E.coli Not detectable

Undetected

Salmonellas Not detectable

Undetected

Conclusion: Conforms to USP32 Standard