Rapid magnetofluidic mixing in a uniform magnetic field.

This paper reports the investigation of mixing phenomena caused by the interaction between a uniform magnetic field and a magnetic fluid in a microfluidic chamber. The flow system consists of a water-based ferrofluid and a mixture of DI water and glycerol. Under a uniform magnetic field, the mismatch in magnetization of the fluids leads to instability at the interface and subsequent rapid mixing. The mismatch of magnetization is determined by concentration of magnetic nanoparticles. Full mixing at a relatively low magnetic flux density up to 10 mT can be achieved. The paper discusses the impact of key parameters such as magnetic flux density, flow rate ratio and viscosity ratio on the mixing efficiency. Two main mixing regimes are observed. In the improved diffusive mixing regime under low field strength, magnetic particles of the ferrofluid migrate into the diamagnetic fluid. In the bulk transport regime under high field strength, the fluid system is mixed rapidly by magnetically induced secondary flow in the chamber. The mixing concept potentially provides a wireless solution for a lab-on-a-chip system that is low-cost, robust, free of induced heat and independent of pH level or ion concentration.

[1]  John P. McTague,et al.  Magnetoviscosity of Magnetic Colloids , 1969 .

[2]  M. Wertheim.  Exact Solution of the Mean Spherical Model for Fluids of Hard Spheres with Permanent Electric Dipole Moments , 1971 .

[3]  Suhas V. Patankar,et al.  A Calculation Procedure for Two-Dimensional Elliptic Situations , 1981 .

[4]  M. Takayasu,et al.  Generalization of HGMS theory: The capture of ultra-fine particles , 1983 .

[5]  A. Lebedev,et al.  The effect of magneto-dipole interactions on the magnetization curves of ferrocolloids , 1990 .

[6]  E. Blums.  Mass transfer in nonisothermal ferrocolloids under the effect of a magnetic field , 1999 .

[7]  Kevin Barraclough,et al.  I and i , 2001, BMJ : British Medical Journal.

[8]  Kee Suk Ryu,et al.  A magnetic microstirrer and array for microfluidic mixing , 2002 .

[9]  Masashige Shinkai.  Functional magnetic particles for medical application. , 2002, Journal of bioscience and bioengineering.

[10]  Guangshan Li,et al.  Microfluidic devices for fluidic circulation and mixing improve hybridization signal intensity on DNA arrays. , 2003, Lab on a chip.

[11]  John Alderman,et al.  Structuring laminar flows using annular magnetohydrodynamic actuation , 2003 .

[12]  Bruce A. Finlayson,et al.  Finite element model of magnetoconvection of a ferrofluid , 2003 .

[13]  Q. Pankhurst,et al.  Applications of magnetic nanoparticles in biomedicine , 2003 .

[14]  H. Pleiner,et al.  Influence of a magnetic field on the Soret-effect-dominated thermal convection in ferrofluids. , 2004, Physical review. E, Statistical, nonlinear, and soft matter physics.

[15]  S. Sen,et al.  Heat transfer augmentation using a magnetic fluid under the influence of a line dipole , 2004 .

[16]  Nam-Trung Nguyen,et al.  Micromixers?a review , 2005 .

[17]  Nam-Trung Nguyen,et al.  Rapid Mixing Using Two-Phase Hydraulic Focusing in Microchannels , 2005, Biomedical microdevices.

[18]  R Zengerle,et al.  Batch-mode mixing on centrifugal microfluidic platforms. , 2005, Lab on a chip.

[19]  Nam-Trung Nguyen,et al.  Convective–diffusive transport in parallel lamination micromixers , 2005 .

[20]  T. Jue.  ANALYSIS OF COMBINED THERMAL AND MAGNETIC CONVECTION FERROFLUID FLOW IN A CAVITY , 2006 .

[21]  Nicole Pamme,et al.  Magnetism and microfluidics. , 2006, Lab on a chip.

[22]  H. Koser,et al.  Overcoming the Diffusion Barrier: Ultra-Fast Micro-Scale Mixing Via Ferrofluids , 2007, TRANSDUCERS 2007 - 2007 International Solid-State Sensors, Actuators and Microsystems Conference.

[23]  Doina Bica,et al.  Magnetic nanoparticles and concentrated magnetic nanofluids： Synthesis, properties and some applications , 2007 .

[24]  M. R. Bahmanyar,et al.  A numerical design study of chaotic mixing of magnetic particles in a microfluidic bio-separator , 2007 .

[25]  H. Pleiner,et al.  Magnetic-field-driven instability in stratified ferrofluids. , 2007, Physical review. E, Statistical, nonlinear, and soft matter physics.

[26]  K. Yao,et al.  CFD study on the magnetic fluid delivering in the vessel in high-gradient magnetic field , 2008 .

[27]  Seyyed Mohammad Mousavi,et al.  CFD simulation and evaluation of controllable parameters effect on thermomagnetic convection in ferrofluids using Taguchi technique , 2008 .

[28]  Chien-Hsiung Tsai,et al.  Rapid magnetic microfluidic mixer utilizing AC electromagnetic field , 2009, Electrophoresis.

[29]  A. Asundi,et al.  Modelling and optimization of micro optofluidic lenses. , 2009, Lab on a chip.

[30]  Matteo Smerlak,et al.  Anomalous diffusion in microchannel under magnetic field , 2010 .

[31]  Numerical analysis of a rapid magnetic microfluidic mixer , 2011, Electrophoresis.

[32]  Nam-Trung Nguyen,et al.  Nonlinear deformation of a ferrofluid droplet in a uniform magnetic field. , 2011, Langmuir : the ACS journal of surfaces and colloids.

[33]  Jing Liu,et al.  Numerical study of the formation process of ferrofluid droplets , 2011 .

[34]  Leidong Mao,et al.  Analytical model of microfluidic transport of non-magnetic particles in ferrofluids under the influence of a permanent magnet , 2011 .

[35]  Numerical study of magnetic nanoparticles concentration in biofluid (blood) under influence of high gradient magnetic field , 2011 .

[36]  W. Marsden.  I and J , 2012 .

[37]  Nam-Trung Nguyen,et al.  Micro-magnetofluidics: interactions between magnetism and fluid flow on the microscale , 2012 .

[38]  Aaas News,et al.  Book Reviews , 1893, Buffalo Medical and Surgical Journal.