- Identity
- Infrared spectrum matched to a reference standard, plus specific optical rotation, which confirms the L-form of lysine.
- Assay
- Purity on a dried basis by nonaqueous titration or HPLC, reported against the USP, FCC or supplier specification.
- Related substances
- Other amino acids and related compounds by HPLC or TLC, which show how cleanly the material was purified.
- Loss on drying and residue on ignition
- Moisture by loss on drying and inorganic residue as residue on ignition (sulfated ash), with chloride and sulfate where the specification lists them.
- Heavy metals and microbiology
- Lead, arsenic, cadmium and mercury by ICP-MS, plus total plate count, yeast and mold, E. coli and Salmonella.
- Chloride
- Chloride content for the hydrochloride, which confirms the salt form.