Reversed-phase ion-pair chromatographic method for the determination of nitroprusside in photolyzed solutions

✍ Scribed by O.R. Leeuwenkamp; E.J. van Mark; P.M. van der Klauw; W.P. van Bennekom; A. Bult

• Publisher: Elsevier Science
• Year: 1984
• Tongue: English
• Weight: 565 KB
• Volume: 161
• Category: Article
• ISSN: 0003-2670
• DOI: 10.1016/s0003-2670(00)85791-8

✦ Synopsis

A rapid reversed-phase ion-pair chromatographic method for disodium pentacyanonitrosylferrate(I1) (nitroprusside) and its photodegradation products nitrite, nitrate, hexacyanoferrate(I1) and hexacyanoferrate(II1) is described. For chromatography, phenyl-bonded pellicular silica gel (10 pm) was used with a mobile phase consisting of water (0.005 M tetrabutylammonium phosphate, 0.0011 M n-octylamine, 0.01 M potassium dihydrogenphosphate, pH 7.0) and methanol (0.005 M tetrabutylammonium phosphate, 0.0011 M n-octylamine) (65:35); the detector was set at 220 nm. In 5% (w/v) dextrose solutions, the calibration graph for nitroprusside was linear over the concentration range lo-120 pg ml-'. A qualitative explanation for the order of retention: hexacyanoferrate( II) < hexacyanoferrate( III) < nitroprusside is given. The method is suitable for the selective determination of nitroprusside in photolyzed infusion solutions (100 pg ml-' in aqueous 5% dextrose) and gives an impression of the decomposition products formed.