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Optical Trapping of Nanoparticles
Published on: January 15, 2013
Photonic-crystal membranes for optical detection of single nano-particles, designed for biosensor application
Jon Olav Grepstad1, Peter Kaspar, Olav Solgaard
1Department of Electronics and Telecommunications, Norwegian University of Science and Technology, NO-7491 Trondheim, Norway. jonolav.grepstad@sintef.no
Optics Express
|March 29, 2012
Summary
This study presents a novel biosensor using a 2D photonic crystal (PC) membrane to detect nanoparticles. The sensor achieves sub-diffraction limit detection, identifying 75 nm particles with high optical fields.
Area of Science:
- Nanotechnology
- Optical Physics
- Biomedical Engineering
Background:
- Optical detection of nanoscale particles is limited by diffraction.
- Photonic crystals offer unique optical field confinement properties.
Purpose of the Study:
- To design and fabricate a biosensor for detecting nanoparticles below the diffraction limit.
- To demonstrate the sensor's capability using a trapped nanoparticle.
Main Methods:
- Fabrication of a sub-micron thick 2D photonic crystal membrane with through holes.
- Development of an imaging system integrating an optical microscope and CCD camera.
- Trapping a nanoparticle within the photonic crystal membrane for detection.
Main Results:
- The photonic crystal membrane generates high optical fields for enhanced detection.
- Trapped nanoparticles appear as bright spots in captured images.
- Experimental validation confirmed the detection of single nanoparticles with a 75 nm radius.
Conclusions:
- The developed photonic crystal biosensor enables sub-diffraction limit nanoparticle detection.
- This technology has potential applications in sensitive bio-molecule detection.
- The sensor design offers a promising platform for advanced nanoscale imaging and sensing.
