Octabromo-tetrakis(4-methylpyridyl)porphineを用いる銅イオンの吸光光度定量

抄録

  Octabromo-tetrakis(4-methylpyridyl)porphine (OBTMPyP), an octabromonated compound with 4 pyrole rings of tetrakis(4-methylpyridyl)porphine, selectively forms a complex with Cu²⁺ ions at pH 2.0. When 3.6×10⁻⁵ mol/L OBTMPyP was added to the reaction mixture, the calibration curve showed good linearity for Cu²⁺ ions ranging from 0.01-2.2 µg (addition of 1.0 mL). A good coefficient of variation (Cu²⁺ions=1.5 µg (addition of 1.0 mL), n=10, 0.8%) was obtained. The molar absorption coefficient (ε) based on Cu²⁺ ions was 8.5×10⁴ L/mol•cm. This value was 6-fold greater than that determined with a clinical chemical analysis kit using the bathocuproine sulfonic acid method, which is a well-known method for spectrophotometric determination of the Cu²⁺ ion concentration. A deproteination method was successfully applied in the clinical analysis kit for determination of Cu²⁺ ion concentrations in control serum I, and the values determined using this method and the bathocuproine sulfonic acid method were almost the same.