Triaxial AFM Probes for Noncontact Trapping and Manipulation

School of Engineering and Applied Sciences, and Department of Physics, Harvard University, Cambridge, Massachusetts 02138, United States.
Nano Letters (Impact Factor: 13.59). 08/2011; 11(8):3197-201. DOI: 10.1021/nl201434t
Source: PubMed


We show that a triaxial atomic force microscopy probe creates a noncontact trap for a single particle in a fluid via negative dielectrophoresis. A zero in the electric field profile traps the particle above the probe surface, avoiding adhesion, and the repulsive region surrounding the zero pushes other particles away, preventing clustering. Triaxial probes are promising for three-dimensional assembly and for selective imaging of a particular property of a sample using interchangeable functionalized particles.

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Available from: Keith Brown, Sep 23, 2015
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    • "The use of a triaxial probe to generate a dielectrophoresis field that acts as a non-contact trap for dielectric nanoparticles has been recently demonstrated [12] [13]. This method is proposed to work for particles as small as 5 nm [13] and has been verified for the isolation of 100 nm polystyrene beads [12]. Although maintaining non-contact avoids potential problems with adhesive forces, the ultimate spatial positioning of targeted particles would be too inconsistent due to the randomizing effects of "
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