title: Shape separation of gold nanorods using centrifugation.
abstract: We demonstrate the use of centrifugation for efficient separation of colloidal gold nanorods from a mixture of nanorods and nanospheres. We elucidate the hydrodynamic behavior of nanoparticles of various shapes and illustrate that the shape-dependent drag causes particles to have shape-dependent sedimentation behavior. During centrifugation, nanoparticles undergo Brownian motion under an external field and move with different sedimentation velocities dictated by their Svedberg coefficients. This effects a separation of particles of different shape and size. Our theoretical analysis and experiments demonstrate the viability of using centrifugation to shape-separate a mixture of colloidal particles.
authors.affiliation: School of Polymer Textile and Fiber Engineering, Center for Advanced Research on Optical Microscopy, and School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA 30332, USA.
authors.forename: Vivek
authors.initials: V
authors.lastname: Sharma
authors.forename: Kyoungweon
authors.initials: K
authors.lastname: Park
authors.forename: Mohan
authors.initials: M
authors.lastname: Srinivasarao
mesh_terms: D002498:Centrifugation / Q000379:methods*; D003102:Colloids / Q000737:chemistry; D006046:Gold; D053768:Metal Nanoparticles; D009038:Motion; D053758:Nanoparticles
chemical_list: D003102:Colloids; D006046:Gold