Appearance: white crystalline power molecular formula: c9h13n5o4, molecular weight: 255.23, cas no.: 82410-32-0, quality standard:cp2005.\n\n1. loss on drying:<=6.0%\n\n2. heavy metals:<=20ppm\n\n3. assay: >=99.0%(titration)\n\n4. melting point:250-300(degree)\n\n5. related substance:<=1.0%\n\n6. limit for guanine :<=0.7%\n\n7. residue on ignition:<=0.1%\n\n8. absorption coefficient:516-548 at 252nm\n\n9. acidity: ph 7.0-8.0.