Separation, isolation and characterization of the four monoiodinated insulin tracers using reversed-phase high-performance liquid chromatography.

Baseline separation between insulin and insulin monoiodinated in Tyr A14, A19, B16 and B26 can be obtained using isocratic elution from a C18 column with triethylammonium trifluoroacetate-acetonitrile and the iodinated insulin derivatives can be isolated by lyophilization. Compared with similar tracers purified and isolated by disc electrophoresis/ion-exchange chromatography, the reversed-phase high-performance liquid chromatographically purified tracers are more homogeneous but show reduced binding affinity to adipocytes.