Science in China Series B: Chemistry

, Volume 40, Issue 6, pp 561–567 | Cite as

Polarographic immunoassay coupled with catalytic amplification of labeled copper ions

  • Song Junfeng 
  • Zhao Mingren 
  • Guo Wei 
  • Wang Jianxiu 


A new approach of polarographic immunoassay based on the catalytic amplification of the labeled metal ions and the polarographic detection of the catalytic product was developed. In this approach, the copper ions used as the catalyst for substrate conversion instead of natural enzyme were labeled to model antigen diphtheria toxoid (DT) through the bifunctional chelating reagent diethylenetriamine pentaacetic acid (DTPA). After heterogeneous competitive immunoreaction, the oxidation of substrate o-phenylenediamine (OPD) was catalyzed by the labeled copper ions to generate an electroactive product 2. 3-diaminophenazine (DAP); subsequently, the product DAP was detected with linear-sweep polarography. The proposed assay can determine the concentration in the range of 10–1000 ng/mL of DT, two orders of magnitude more sensitive than those based on the direct detection of the metal ion labels. The proposed immunoassay can be applied to detecting various proteins of interest.


diphtheria toxoid (DT) copper catalytic amplification immunoassay linear-sweep polarography 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    Hu, Y. H., Tie, F., Li, Q. M., Homogeneous voltammetric immunoassay of diphtheria toxoid and DAT,Chemical J. Chinese Universities (in Chinese), 1987, 8(9): 793.Google Scholar
  2. 2.
    Hu, Y. H., Li, Q. M., The study on voltammertric immunoassay—Polarographic determination of cadmium labeled diphtheria toxoid and diphtheria antitoxin,J. Northwest University (Natural Science Ed.) (in Chinese), 1986, 16(1): 38.Google Scholar
  3. 3.
    Xu, J. Q., Song, J. F., Guo, W., Polarographic enzyme-immunoassay for trace Hepatitis B surface antigen (HBsAg),Anal. Lett., 1996, 29(4): 565.Google Scholar
  4. 4.
    Hnatowich, D. J., Layne, W. W., Childs, R. L., The preparation and labeling of DTPA-coupled albumin,Int. J. Appl. Radiat. Isot., 1982, 33(5): 327.CrossRefGoogle Scholar
  5. 5.
    Zhu, Z. G., Fu, X. W., Lu, H. Z., Determination of serum copper content in 86 healthy children,Spectrosc. Spectral Anal. (in chinese), 1991, 11(5): 71.Google Scholar
  6. 6.
    Hayes, F. J., Halsall, H. B., Heineman, W. R., Simultaneous immunoassay using electrochemical detection of metal ion labels,Anal. Chem., 1994, 66: 1860.CrossRefGoogle Scholar
  7. 7.
    Peng, S. M., Liaw, D. S., Copper(II) ion catalytic oxidation ofo-phenylenediamine and diaminomaleonitrile and the crystal structure of the final products 2. 3-diaminophenazine perchlorate-hydrate and hexacyanotetrakis (dimethylformamide) penta-copper,Inorg. Chim. Acta, 1986, 113(1): L11.CrossRefGoogle Scholar
  8. 8.
    Tarcha, P. J., Chu, V. P., Whittern, D., 2, 3-diaminophenazine is the product from HRP-catalyzed oxidation ofo-phenylenediamlne,Anal. Biochem., 1987, 165(1): 230.CrossRefGoogle Scholar
  9. 9.
    Ma, Z. C., Yang, S. H., Catalytic spectrophotometric determination of trace copper,Anal. Lab. (Fenxi Shiyanshi) (in Chinese), 1983, 2(5): 23.Google Scholar
  10. 10.
    Zhao, M. R., Wang, J. X., Song, J. F., Determination of trace copper by catalytic oscillopolarography,J. Northwest University (Natural Science Ed.) (in Chinese), 1994, 24(s): 279.Google Scholar
  11. 11.
    Inczedy, J.,Analytical Applications of Complex Equilibria, New York: Halsted Press, 1976, 337.Google Scholar
  12. 12.
    Nakamura Setsuko, Polarographic reduction of phenazine,Electrochemistry (Denki Kagaku) (in Japanese), 1971, 39(6): 502.Google Scholar

Copyright information

© Science in China Press 1997

Authors and Affiliations

  • Song Junfeng 
    • 1
  • Zhao Mingren 
    • 1
  • Guo Wei 
    • 1
  • Wang Jianxiu 
    • 1
  1. 1.Northwest UniversitInstitute of Electroanalytical ChemistryChina

Personalised recommendations