Assay
Ferric chloride solution
Dissolve 6.7g of ferric chloride in dilute hydrochloric acid (1in 100)in a 100-mLvolumetric flask.Add dilute hydrochloric acid (1in 100)to volume,mix,and filter.
Standard preparation
Dissolve a suitable quantity of
USP Deferoxamine Mesylate RS,accurately weighed,in water to obtain a solution having a known concentration of about 1000µg per mL.
Assay preparation
Dissolve about 50mg of Deferoxamine Mesylate,accurately weighed,in water to make 50.0mL,and mix.
Procedure
Pipet 2mLeach of the
Standard preparation,the
Assay preparation,and water to provide a blank,into separate 25-mLvolumetric flasks.To each flask add 3mLof
Ferric chloride solution,dilute with water to volume,and mix.Concomitantly determine the absorbances of the solutions from the
Standard preparationand the
Assay preparationagainst the blank,in 1-cm cells,at the wavelength of maximum absorbance at about 485nm,with a suitable spectrophotometer.Calculate the quantity,in mg,of C
25H
48N
6O
8·CH
4O
3Sin the portion of Deferoxamine Mesylate taken by the formula:
0.05C(AU/AS),
in which
Cis the concentration,in µg per mL,of
USP Deferoxamine Mesylate RSin the
Standard preparation,and
AUand
ASare the absorbances of the solutions from the
Assay preparationand
Standard preparation,respectively.