Doxofylline

Identification

A.H-NMR:Comply with the structure

Complies

B.LC-MS:Comply with the structure

Complies

C.The IR spectrum of sample should be identical with that of reference standard.

Complies

D.HPLC-ESI-MS

The retention time of the major peak in the chromatogram of the Assay preparation corresponds to that in the chromatogram of the Standard preparation, as obtained in the Assay.

Complies

Loss on drying

≤2.0%

0.19%

Heavy metals

≤10 ppm

<10ppm

Water

≤1.0%

0.1%

Sulphated ash

≤0.5% determined on 1.0 g.

0.009%

Residue on ignition

≤0.1%

0.03%

Related Substances

Unspecified impurities: for each impurity ≤0.10%

<0.10%

Total Impurity ≤0.5%

0.18%

Purity

≥99.0%

99.7%

Assay

99.0%~101.0% (anhydrous substance).

99.8%

Storage

Preserve in well-closed, light-resistant and airtight containers.

Complies