Phthalocyanine derivatives as mobile-phase modifiers for the indirect detection of fullerenes in high-performance liquid chromatography

Octadecylsulfamoyl and tert-butyl derivatives of phthalocyanine were studie d as mobile-phase modifiers for the indirect detection of fullerenes. It wa s demonstrated that the sensitivity of determining fullerenes with indirect spectrophotometric detection at 669 nm depends on the nature of the modifi er, its concentration in the mobile phase, and the temperature of the colum n. When the terta-4-tert-butylphthalocyanine complex of zinc was used as th e modifier of the ethyl acetate-acetonitrile (9 : 1) mobile phase, the sens itivity of determining C-60 was twice as high as for the direct detection ( 368 nm). The chromatograms (669 nm) of benzene extracts of graphite black g ive an estimate of the actual ratio between fullerenes and products of thei r synthesis and can be used for the rapid determination of the ratio and co ncentrations of C-60 and C-70 fullerenes in samples.