Wash-free immunomagnetic detection for serum through magnetic susceptibility reduction

In this study, a platform for wash-free immunomagnetic detections is discussed. The reagent is a magnetic fluid composed of biofunctionalized magnetic particles dispersed in water. The assay instrument is a mixed-frequency magnetosusceptometer. The mixed-frequency ac magnetic susceptibility χac of the magnetic reagent is reduced, as a result of the formation of magnetic clusters via the association among magnetic nanoparticles and a specific biotarget. The immunoassay detection of proteins in water, such as aqueous c-reactive protein, is characterized and is compared to that in serum. These observations demonstrate the advantages of high convenience, high sensitivity, and high specificity for χac-reduction immunomagnetic detection.

[1]  M. Novotny,et al.  Recent advances in capillary electrophoresis of proteins, peptides and amino acids , 1990, Electrophoresis.

[2]  Dieter Stoll,et al.  Protein microarray technology. , 2002, Frontiers in bioscience : a journal and virtual library.

[3]  H. C. Yang,et al.  Biofunctionalized magnetic nanoparticles for high-sensitivity immunomagnetic detection of human C-reactive protein , 2006 .

[4]  N. A. Yusuf.  The Transient Behavior of Light Transmission and Faraday Rotation in Magnetic Fluids , 1988 .

[5]  Shieh-Yueh Yang,et al.  Magnetic susceptibility reduction method for magnetically labeled immunoassay , 2006 .

[6]  S. Schreiber,et al.  Printing proteins as microarrays for high-throughput function determination. , 2000, Science.

[7]  Lutz Trahms,et al.  Determination of the binding reaction between avidin and biotin by relaxation measurements of magnetic nanoparticles , 1999 .

[8]  Shieh-Yueh Yang,et al.  Magnetic relaxation measurement in immunoassay using high-transition-temperature superconducting quantum interference device system , 2006 .

[9]  L. J. Greenberg,et al.  Application of differential light scattering to the latex agglutination assay for rheumatoid factor. , 1975, Clinical chemistry.

[10]  John Clarke,et al.  Magnetic gradiometer based on a high-transition temperature superconducting quantum interference device for improved sensitivity of a biosensor , 2002 .

[11]  J. Grange,et al.  Nephelometric assay of antigens and antibodies with latex particles. , 1977, Journal of immunological methods.

[12]  N. Hamasaki,et al.  Biological Immunoassay Utilizing Magnetic Marker and High Tc Superconducting Quantum Interference Device Magnetometer , 2003 .