Ultrahigh sensitivity made simple: nanoplasmonic label-free biosensing with an extremely low limit-of-detection for bacterial and cancer diagnostics
Journal article, 2009

We present a simple and robust scheme for biosensing with an ultralow limit-of-detection down to several pg cm−2 (or several tens of attomoles cm−2) based on optical label-free biodetection with localized surface plasmon resonances. The scheme utilizes cost-effective optical components and comprises a white light source, a properly functionalized sensor surface enclosed in a simple fluidics chip, and a spectral analyzer. The sensor surface is produced by a bottom-up nanofabrication technique with hole mask colloidal lithography. Despite its simplicity, the method is able to reliably detect protein–protein binding events at low picomolar and femtomolar concentrations, which is exemplified by the label-free detection of the extracellular adherence protein (EAP) found on the outer surface of the bacterium Staphylococcus aureus and of prostate-specific antigen (PSA), which is believed to be a prostate cancer marker. These experiments pave the way towards an ultra-sensitive yet compact biodetection platform for point-of-care diagnostics applications.


Si Chen

Chalmers, Applied Physics, Bionanophotonics

Mikael Svedendahl

Chalmers, Applied Physics, Bionanophotonics

Mikael Käll

Chalmers, Applied Physics, Bionanophotonics

Linda K Gunnarsson

Chalmers, Applied Physics, Bionanophotonics

Alexander Dmitriev

Chalmers, Applied Physics, Bionanophotonics


0957-4484 (ISSN) 1361-6528 (eISSN)

Vol. 20 43 434015- 434015

Subject Categories

Atom and Molecular Physics and Optics




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