[Immunogold dot assay for diagnosis of early pregnancy].

Two monoclonal antibodies anti-HCG were prepared. One anti-alpha HCG was directly labeled with colloidal gold, and the other, anti-beta HCG was coated on nitrocellulose membrane as dot. After determination of optimal conditions of the system, an immunogold dot blot assay for testing HCG in urine sample was established. The sensitivity of the assay was 50 mIU HCG/ml, corresponding to the content of HCG in the urine of women about 30 days after last menstruation. The assay has been evaluated in clinical trial. All the testing results accorded with clinical diagnosis. No false positive results appeared. This simple, rapid and stable assay is ideal for women to diagnose early pregnancy at home.