Prion protein detection using nanomechanical resonator arrays and secondary mass labeling.
Nanomechanical resonators have shown potential application for mass sensing and have been used to detect a variety of biomolecules. In this study, a dynamic resonance-based technique was used to detect prion proteins (PrP), which in conformationally altered forms are known to cause neurodegenerative diseases in animals as well as humans. Antibodies and nanoparticles were used as mass labels to increase the mass shift and thus amplify the frequency shift signal used in PrP detection. A sandwich assay was used to immobilize PrP between two monoclonal antibodies, one of which was conjugated to the resonator's surface while the other was either used alone or linked to the nanoparticles as a mass label. Without additional mass labeling, PrP was not detected at concentrations below 20 microg/mL. In the presence of secondary antibodies the analytical sensitivity was improved to 2 microg/mL. With the use of functionalized nanoparticles, the sensitivity improved an additional 3 orders of magnitude to 2 ng/mL.
Varshney
Madhukar
M
School of Applied and Engineering Physics, Department of Biomedical Engineering, Cornell University, Ithaca, New York 14853, USA.
Waggoner
Philip S
PS
Tan
Christine P
CP
Aubin
Keith
K
Montagna
Richard A
RA
Craighead
Harold G
HG
D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D006801:Humans; D036103:Nanotechnology / Q000295:instrumentation*; D011328:Prions / Q000032:analysis* / Q000276:immunology
D000911:Antibodies, Monoclonal; D011328:Prions