ال متیونین کد 105707 مرک آلمان





L-Methionine
for biochemistry
Synonym(s): L-Methionine, Met
 

Analysis Note
Assay (perchloric acid titration, calculated on dried substance) ≥ 99.0 %
Identity (IR-spectrum) passes test
Appearance white or almost white, crystalline powder or colorless crystals
Appearance of solution (0.5 mol/l, hydrochloric acid 1 mol/l) clear and colorless
Spec. rotation (α 20/D, 50 g/l, hydrochloric acid 1 mol/l, calc. on dried substance) +22.5 to +23.5
UV-Absorption (260 nm, 0.5 mol/l, 1 cm, hydrochloric acid 1 mol/l) ≤ 0.50
UV-Absorption (280 nm, 0.5 mol/l, 1 cm, hydrochloric acid 1 mol/l) ≤ 0.20
Chloride (Cl) ≤ 0.02 %
Sulfate (SO₄) ≤ 0.01 %
Heavy metals (as Pb) ≤ 0.001 %
As (Arsenic) ≤ 0.0005 %
Ca (Calcium) ≤ 0.001 %
Co (Cobalt) ≤ 0.0005 %
Fe (Iron) ≤ 0.0005 %
K (Potassium) ≤ 0.0005 %
Mg (Magnesium) ≤ 0.0005 %
Na (Sodium) ≤ 0.005 %
NH₄ (Ammonium) ≤ 0.01 %
Zn (Zinc) ≤ 0.0005 %
Foreign amino acids ≤ 0.3 %
Other ninhydrine positive substances ≤ 0.1 %
Loss on drying (105 °C; 3 h) ≤ 0.3 %