Abstract
A highly sensitive, specific method for the determination of serum copper was described, for which water-soluble porphyrin as chelating reagent firstly has been used. The molor absorptivity of porphyrin (TMPyP; εeffective=2.3×105) is twenty fold higher than that of bathocuproine. Reducing reagent (CySH) was required not only for the formation of TCA deproteinization system but also for the promotion of the chelating of TMPyP-Cu.
The serum sample (0.2ml) was deproteinized with CySH-HCI-TCA reagent and the supe-rnatant was mixed TMPyP buffer at pH 4.7 for 5 min, then add H2SO4 and mix. Measure the absorbance of the Blank (B), Test (T), and 200μg Cu/100ml as calculated on followed formula standard (S) at 447nm.
(B-T)/(B-S)×200=Serum copper (μg/100ml).
The other serum components (ex. iron, zinc and ascorbic acid) were not interfered.
Reproducibility in the serum for which coPPer of 129.3μg/100ml was±2.865 and 2.22% of C. V. The correlation coefficent of the present method to bathocuproine method was 0.996.