Abstract: The present invention is directed to the development of a biosensor based on the immuno-chromatographic method that can provide an assay speed and convenience required for point-of-care (the doctor's office and emergency room) testing or home-version diagnosis. Though certain physical symptoms, such as pregnancy and ovulation, or bacterial infection may be identified by a qualitative analysis for the presence of indicating substances, most analytes for clinical investigation demand their concentrations known in specimens. Therefore, the inventors of the present invention have developed a novel biosensor by combining the immuno-chromatographic method and the electric conductivity detection technology so that on-site quantitative determination at the points of care or at home may be carried out.