Determination of Related Substances in Foscarnet Sodium by HPLC / 医药导报

ABSTRACT

Objective To establish a method for the determination of related substances in foscarnet sodium by HPLC.Methods The chromatography separation was performed on a CAPCELL PAK C18 chromatography column(250 mm×4.6 mm,5 μm)with mobile phase of a mixture of solution[Solution Adissolve 3.2 g of sodium sulfate decahydrate in water,add 3 mL of glacial acetic acid and 6 mL of 0.1 mol·L-1 sodium pyrophosphate,dilute with water to 1 000 mL.Solution Bdissolve 3.2 g of sodium sulfate decahydrate in water,add 6.8 g of sodium acetate and 6 mL of 0.1 mol·L-1 sodium pyrophosphate,dilute with water to 1000mL.Solution A and Solution B(70∶30)(the pH of this mixture is about 4.4).To 1 000 mL of this solution add 0.25 g of tetrahexylammonium hydrogen sulfate and 100 mL of methanol]at a flow rate of 1.0 mL·min-1.The column temperature was 35℃.The detection wavelength was 230 nm and the injection volume was 50 μL.Results Under the chromatography conditions,the peaks of foscarnet sodium,impurityⅠ,impurity Ⅱ and other individual impurities were separated effectively.The foscarnet sodium and impurity Ⅱ showed good liner relationships(r=0.999 9)in the range of 5-248 μg·mL-1 and 1.6-9.1 μg·mL-1,respectively.The limits of detection(LODs)of foscarnet sodium and impurity Ⅱ were 23 ng and 62 ng respectively.The average recovery of impurity Ⅰ was 100.8%,RSD= 2.0%(n= 6).The average recovery of impurity Ⅱ was 98.6%,RSD=2.7%(n=12).Conclusion The method is simple,sensitive and accurate.It is suitable for the determination of related substances in foscarnet sodium.