Hypersensitive immunoassay by using <i>Escherichia coli</i> outer membrane with autodisplayed Z-domains

다국어 초록 (Multilingual Abstract)

<P><B>Abstract</B></P><P>In this work, the Z-domain of protein A was autodisplayed on the surface of the <I>Escherichia coli</I> outer membrane as a fusion protein of AIDA-1, and then layered on a microplate in order to develop a hypersensitive immunoassay. By using microplates with controlled hydrophilicity the formation of outer membrane layer was carried out, and the driving force for the layer formation was proven to be a hydrophobic interactions. Through the orientation control of the immobilized antibodies by using autodisplayed Z-domains, the limit of detection (LOD) and the sensitivity of this new immunoassay were determined to have improved as much as 30-fold compared to the conventional ELISA. The applicability of the new immunoassay for medical diagnosis was demonstrated by the detection of C-reactive protein (CRP) which is known to be a biomarker protein for inflammatory diseases.</P>