Objective   To establish a new method for the detection of anti-Toxoplasma IgG antibodies (TOXO IgG) in serum and to evaluate its preliminary significance in clinical application.    Methods   The immunomagnetic beads were prepared by coating Toxoplasma antigen onto the surfaces of magnetic microspheres. The purified conjugate of goat anti-human IgG labeled with QDs was used as the second antibody. Then the TOXO IgG in the serum samples were detected and then the detection conditions were optimized. The serum of 255 pregnant women was assayed with this new method. The results were analyzed and compared with those by the DiaSorin TOXO IgG ELISA kit made in Italy.     Results   The best test conditions were determined as follows: the magnetic microspheres coated by Toxoplasma antigen at the concentration of 100  μg/ml

the working dilution of QDs-labeled rabbit anti-mice IgG at 1∶200

and dilution of serum samples at 1∶100. The sensitivity and specificity were 93.3% and 96.7%

respectively. The coincidence rate with the imported kit reached as high as 96.5%.     Conclusion   The method established in this study is of easy operation

fast reaction

and reliable result

and may be of potential value in clinical application.