Patent ID: 8394600

Claim:
A method for diagnosing syphilis in a subject, comprising: applying a biological sample from a subject to a device, wherein the device is made by a method comprising: preparing a lipoidal antigen in a non-aqueous solution; mixing the lipoidal antigen in a non-aqueous solution with an aqueous solution to generate lipoidal micelles; centrifuging the lipoidal micelles to generate a supernatant comprising small lipoidal antigen micelles having an average diameter of less than 5 microns; and applying the small lipoidal antigen micelles to the microporous membrane having a proximal sample application area and a detection zone with a predetermined pore size, wherein the small antigen micelles enter and are retained in the pores of the detection zone, thereby forming an immunoassay device for detection of anti-lipoidal antibodies; detecting formation of an immunocomplex between an anti-lipoidal antibody present in the biological sample and the small lipoidal antigen micelles in the pores of the detection zone of the immunoassay device; and diagnosing syphilis in the subject when the immunocomplex is detected.