Assay (perchloric acid titration, calculated on dried substance): ≥ 99.0

Identity (IR-spectrum): passes test

Appearance: colorless to white, needle-shaped crystals

Appearance of solution (100 g/l, hydrochloric acid  2 mol/l): clear and colorless

Spec. rotation (α 20/D, 80 g/l, hydrochloric acid 1 mol/l, calc.on dried substance): +8.3 to +9.5

pH (25 g/l; CO₂-free water): 4.5 - 5.5

Chloride (Cl): ≤ 0.04 %

Sulfate (SO₄): ≤ 0.03 %

Heavy metals (as Pb): ≤ 0.001 %

As (Arsenic): ≤ 0.0001 %

Ca (Calcium): ≤ 0.001 %

Co (Cobalt): ≤ 0.0005 %

Fe (Iron): ≤ 0.0010 %

K (Potassium): ≤ 0.0005 %

Mg (Magnesium): ≤ 0.0005 %

Na (Sodium): ≤ 0.01 %

NH₄ (Ammonium): ≤ 0.02 %

Zn (Zinc): ≤ 0.0005 %

Foreign amino acids: ≤ 0.5 %

Other ninhydrine positive substances: ≤ 0.1 %

Loss on drying (105 °C; 3 h): ≤ 0.5 %