Assay (anhydrous basis): 99.0 to 100.5%
Loss on drying: ≤1.0%
Alkalinity: meets USP/FCC standard
pH (5g/100mL at 25 ℃): 7.5 to 9.0
Tartrate: meets USP standard
Heavy metals: ≤10ppm
Lead: <2ppm
Residual solvents: meets USP standard