title: A novel viscoelastic-based ferrofluid for continuous sheathless microfluidic separation of nonmagnetic microparticles.
abstract: Separation of microparticles has found broad applications in biomedicine, industry and clinical diagnosis. In a conventional aqueous ferrofluid, separation of microparticles usually employs a sheath flow or two offset magnets to confine particle streams for downstream particle sorting. This complicates the fluid control, device fabrication, and dilutes the particle sample. In this work, we propose and develop a novel viscoelastic ferrofluid by replacing the Newtonian base medium of the conventional ferrofluid with non-Newtonian poly(ethylene oxide) (PEO) aqueous solution. The properties of both viscoelastic 3D focusing and negative magnetophoresis of the viscoelastic ferrofluid were verified and investigated. By employing the both properties in a serial manner, continuous and sheathless separation of nonmagnetic particles based on particle size has been demonstrated. This novel viscoelastic ferrofluid is expected to bring more flexibility and versatility to the design and functionality in microfluidic devices.
authors.affiliation: School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China.
authors.forename: Jun
authors.identifier: 0000-0003-1113-6264
authors.initials: J
authors.lastname: Zhang
authors.affiliation: School of Mechanical, Materials and Mechatronic Engineering, University of Wollongong, Wollongong, NSW 2522, Australia. weihuali@uow.edu.au.
authors.forename: Sheng
authors.initials: S
authors.lastname: Yan
authors.affiliation: School of Mechanical, Materials and Mechatronic Engineering, University of Wollongong, Wollongong, NSW 2522, Australia. weihuali@uow.edu.au.
authors.forename: Dan
authors.initials: D
authors.lastname: Yuan
authors.affiliation: School of Mechanical, Materials and Mechatronic Engineering, University of Wollongong, Wollongong, NSW 2522, Australia. weihuali@uow.edu.au.
authors.forename: Qianbin
authors.initials: Q
authors.lastname: Zhao
authors.affiliation: Queensland Micro and Nanotechnology Centre, Griffith University, Brisbane, QLD 4111, Australia. nam-trung.nguyen@griffith.edu.au.
authors.forename: Say Hwa
authors.initials: SH
authors.lastname: Tan
authors.affiliation: Queensland Micro and Nanotechnology Centre, Griffith University, Brisbane, QLD 4111, Australia. nam-trung.nguyen@griffith.edu.au.
authors.forename: Nam-Trung
authors.initials: NT
authors.lastname: Nguyen
authors.affiliation: School of Mechanical, Materials and Mechatronic Engineering, University of Wollongong, Wollongong, NSW 2522, Australia. weihuali@uow.edu.au.
authors.forename: Weihua
authors.initials: W
authors.lastname: Li
mesh_terms: D004867:Equipment Design; D056656:Lab-On-A-Chip Devices; D060526:Magnetic Fields; D008863:Microspheres; D011092:Polyethylene Glycols / Q000737:chemistry
chemical_list: D011092:Polyethylene Glycols