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Compositional guideline: D-Ribose-L-Cysteine

9 August 2016

Name of the ingredient

D-Ribose-L-Cysteine (AAN)

Definition of the ingredient

Molecular formula: C8H15NO6S

CAS Number: 17087-36-4

Table 1. Ingredient specific requirements
Test Method reference Acceptance criteria
Description
Appearance Visual White to pale yellow powder
Characteristics
pH (0.5 g in 10 ml water) USP <791> 3.0 - 4.0
Solubility BP (General notices) Freely soluble in water; practically insoluble in ethanol and acetone
Clarity of solution (0.5 g in 10 ml water) BP (Appendix IV A) Clear
Loss on Drying BP (Appendix IX D) Not more than 0.5% w/w
Specific optical rotation (1.0 g per 100 ml) USP <781> -125º ±6º
Identification
D-Ribose-L-Cysteine

IR absorbance spectrum

BP (Appendix II A)

Complies with authenticated reference material/spectrum
D-Ribose-L-Cysteine HPLC Complies with the chromatogram for the authenticated reference material
Assay
Assay HPLC 98.0 to 102.0% w/w, on dried basis
Table 2. Incidental constituents
Test Method reference Acceptance criteria
Residual solvents
Residual solvents BP (Appendix VIII L) Meets the requirements of the BP Supplementary Chapter SC IV D
Incidental metals and non-metals
While ingredient manufacturers are encouraged to include limits for Incidental metals and non-metals, it is the product into which those substances are formulated that contains the ingredient, alone or in combination with other ingredients, must comply with the acceptance criteria set in the United States Pharmacopeia - National Formulary general chapter '<2232> Elemental Contaminants in Dietary Supplements'. When testing is performed at the raw material stage, calculation of the total daily exposure in the finished product should be performed. This calculation is based on the quantity of each ingredient present in the product, the maximum potential contamination given the proposed limits for each raw material and the daily dose of the product.
Other organic or inorganic impurities or toxins
Related substances HPLC

L-cysteine not more than 1.0% w/w

L-cystine not more than 1.0% w/w

Any other individual impurity not more than 0.15%w/w.

Total impurities (other than L-cysteine and L-cystine) not more than 0.5%w/w

Microbiology
While substance manufacturers are encouraged to include limits for objectionable microorganisms, it is the product into which those substances are formulated that is subject to a legally binding set of criteria. The Therapeutic Goods Order No. 77 'Microbiological Standards for Medicines' mandates that any finished product that contains the ingredient, alone or in combination with other ingredients, must comply with the microbial acceptance criteria set by Clause 9 of the Order.

Key to abbreviations

BP = British Pharmacopoeia

HPLC = High-pressure liquid chromatography

IR = Infrared spectrophotometry

Ph Eur = European Pharmacopoeia

USP = United States Pharmacopoeia