Magneto immuno-PCR: a novel immunoassay based on biogenic magnetosome nanoparticles.
We describe an innovative modification of the Immuno-PCR technology for automatable high sensitive antigen detection. The Magneto Immuno-PCR (M-IPCR) is based on antibody-functionalized biogenic magnetosome nanoparticles revealing major advantages over synthetic magnetic particles. The general principle of the M-IPCR is similar to that of a two-sided (sandwich) immunoassay. However, antibody-functionalized magnetosome conjugates were employed for the immobilization and magnetic enrichment of the signal generating detection complex enabling the establishment of a surface independent immunoassay. To this end, the M-IPCR was carried out by simultaneously tagging the antigen with the reagent for read-out, i.e., a conjugate comprising the specific antibody and DNA fragments, in the presence of the antibody-functionalized magnetosomes. To demonstrate the general functionality of the M-IPCR, the detection of recombinant Hepatitis B surface Antigen (HBsAg) in human serum was established. We observed a detection limit of 320pg/ml of HBsAg using the M-IPCR, which was about 100-fold more sensitive than the analogous Magneto-ELISA, established in parallel for comparison purposes.
Wacker
Ron
R
Chimera Biotec GmbH, Emil-Figge-Str. 76A, D-44227 Dortmund, Germany.
Ceyhan
Buelent
B
Alhorn
Petra
P
Schueler
Dirk
D
Lang
Claus
C
Niemeyer
Christof M
CM
D003199:Computer Systems; D007118:Immunoassay / Q000379:methods*; D018189:Immunomagnetic Separation / Q000379:methods*; D008280:Magnetics; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D016133:Polymerase Chain Reaction / Q000379:methods*