title: Imaging nanoparticle flow using magneto-motive optical Doppler tomography.
abstract: We introduce a novel approach for imaging solutions of superparamagnetic iron oxide (SPIO) nanoparticles using magneto-motive optical Doppler tomography (MM-ODT). MM-ODT combines an externally applied temporally oscillating high-strength magnetic field with ODT to detect nanoparticles flowing through a microfluidic channel. A solenoid with a cone-shaped ferrite core extensively increased the magnetic field strength (B(max) = 1 T, [Formula: see text]) at the tip of the core and also focused the magnetic field in microfluidic channels containing nanoparticle solutions. Nanoparticle contrast was demonstrated in a microfluidic channel filled with an SPIO solution by imaging the Doppler frequency shift which was observed independently of the nanoparticle flow rate and direction. Results suggest that MM-ODT may be applied to image Doppler shift of SPIO nanoparticles in microfluidic flows with high contrast.
authors.affiliation: Beckman Laser Institute and Medical Clinic, University of California, 1002 Health Sciences Road East, Irvine, CA 92612, USA.
authors.forename: Jeehyun
authors.initials: J
authors.lastname: Kim
authors.forename: Junghwan
authors.initials: J
authors.lastname: Oh
authors.forename: Thomas E
authors.initials: TE
authors.lastname: Milner
authors.forename: J Stuart
authors.initials: JS
authors.lastname: Nelson