3,4-Dihydroxybenzoic acid CAS:99-50-3 CAS NO.99-50-3

item

standard

test results

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

complies

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.

heavy metals

≤10 ppm

<10ppm

water

≤1.0%

0.10%

sulphated ash

≤0.5%, determined on 1.0 g.

0.01%

related substances

unspecified impurities: for each impurity

≤0.10%

<0.10%

total impurity

≤0.5%

0.18%

purity

≥99.0%

99.70%

assay

99.0%~101.0% (anhydrous substance).

99.80%

storage

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

complies