identification

positive

positive

a: infrared absorption spectrum should be the same as that of epcrs

meets the requirement

meets the requirement

b: it gives reaction of sodium

meets the requirement

meets the requirement

appearance of solution

color

not more than intensely colored than reference solution b7 or by7

b7

tests

ph

4.0~5.0

4.4

4-aminobutanoic acid by tlc

≤0.5%

0.5%

phosphate by hplc

≤0.5%

0.5%

phosphite by hplc

≤0.5%

0.5%

heavy metals

≤20ppm

20ppm

loss on drying

16.1%

16.5%

residual methanol

≤200ppm

60ppm

assay

98.0%~102.0%

99.6%