Size Selective Synthesis of Superparamagnetic Nanoparticles in Thin Fluids under Continuous Flow Conditions

Continuous flow spinning disc processing (SDP), which has extremely rapid mixing under plug flow conditions, effective heat and mass transfer, allowing high throughput with low wastage solvent efficiency, is effective in gaining access to superparamagnetic Fe3O4 nanoparticles at room temperature. These are formed by passing ammonia gas over a thin aqueous film of Fe2þ/3þ which is introduced through a jet feed close to the centre of a rapidly rotating disc (500 to 2500 rpm), the particle size being controlled with a narrow size distribution over the range 5 nm to 10 nm, and the material having very high saturation magnetizations, in the range 68–78 emu g-�1.

[1]  J. Takada,et al.  Surface oxidation, size and shape of nano-sized magnetite obtained by co-precipitation , 2006 .

[2]  O. Matar,et al.  Gas absorption into a wavy film flowing over a spinning disc , 2005 .

[3]  A. Chianese,et al.  Process Intensification: Precipitation of Barium Sulfate Using a Spinning Disk Reactor , 2002 .

[4]  J. Popplewell,et al.  The dependence of the physical and magnetic properties of magnetic fluids on particle size , 1995 .

[5]  T. Nagai,et al.  Preparation and characterization of superparamagnetic iron oxide nanoparticles stabilized by alginate. , 2007, International journal of pharmaceutics.

[6]  Mamoun Muhammed,et al.  Characterization and MRI study of surfactant-coated superparamagnetic nanoparticles administered into the rat brain , 2001 .

[7]  Pedro Tartaj,et al.  Microemulsion-Assisted Synthesis of Tunable Superparamagnetic Composites , 2002 .

[8]  Kamelia Boodhoo,et al.  Process intensification: spinning disc reactor for condensation polymerisation , 2000 .

[9]  S. Hayakawa,et al.  Preparation of alginic acid layers on stainless-steel substrates for biomedical applications. , 2003, Biomaterials.

[10]  Gil Markovich,et al.  Ordered Two‐Dimensional Arrays of Ferrite Nanoparticles , 2001 .

[11]  T. A. Hatton,et al.  Bilayer Surfactant Stabilized Magnetic Fluids: Synthesis and Interactions at Interfaces , 1999 .

[12]  M. Seki,et al.  Magnetic properties of ultrafine ferrite particles , 1987 .

[13]  Sangsig Kim,et al.  Sub 5 nm magnetite nanoparticles: Synthesis, microstructure, and magnetic properties , 2007 .

[14]  Colin Ramshaw,et al.  Evaluation of Spinning Disk Reactor Technology for the Manufacture of Pharmaceuticals , 2000 .

[15]  A. Gedanken,et al.  Sonochemical Preparation and Size-Dependent Properties of Nanostructured CoFe2O4 Particles , 1998 .

[16]  Grigori M. Sisoev,et al.  The flow of thin liquid films over spinning disks: Hydrodynamics and mass transfer , 2005 .

[17]  Taeghwan Hyeon,et al.  Ultra-large-scale syntheses of monodisperse nanocrystals , 2004, Nature materials.

[18]  Qiao Sun,et al.  Preparation of water-soluble magnetite nanocrystals from hydrated ferric salts in 2-pyrrolidone: mechanism leading to Fe3O4. , 2004, Angewandte Chemie.

[19]  Taeghwan Hyeon,et al.  Synthesis of highly crystalline and monodisperse maghemite nanocrystallites without a size-selection process. , 2001, Journal of the American Chemical Society.

[20]  F. Feschet,et al.  Nanotips and nanomagnetism , 1998 .

[21]  H. Chan,et al.  Synthesis of Fe3O4 nanoparticles from emulsions , 2001 .

[22]  K. R. Koch,et al.  An investigation into the potential large-scale continuous magnetite nanoparticle synthesis by high-pressure impinging stream reactors , 2007 .

[23]  Ajay Kumar Gupta,et al.  Synthesis and surface engineering of iron oxide nanoparticles for biomedical applications. , 2005, Biomaterials.

[24]  Hongwei Shen,et al.  The colloidal stability and core-shell structure of magnetite nanoparticles coated with alginate , 2006 .

[25]  R. Ziolo,et al.  In Situ Preparation of Nanocrystalline γ-Fe2O3 in Iron(II) Cross-Linked Alginate Gels , 1996 .

[26]  Z. J. Zhang,et al.  Effects of surface coordination chemistry on the magnetic properties of MnFe(2)O(4) spinel ferrite nanoparticles. , 2003, Journal of the American Chemical Society.

[27]  Bing Xu,et al.  Dopamine as a robust anchor to immobilize functional molecules on the iron oxide shell of magnetic nanoparticles. , 2004, Journal of the American Chemical Society.

[28]  Colin Ramshaw,et al.  Process intensification : heat and mass transfer characteristics of liquid films on rotating discs , 1999 .

[29]  Colin Ramshaw,et al.  Measurement of liquid film thickness and the determination of spin-up radius on a rotating disc using an electrical resistance technique , 2003 .

[30]  Keliang Liu,et al.  Size-controlled preparation of magnetite nanoparticles in the presence of graft copolymers , 2006 .

[31]  C. Graham,et al.  Introduction to Magnetic Materials , 1972 .

[32]  Song Gao,et al.  Solvothermal reduction synthesis and characterization of superparamagnetic magnetite nanoparticlesElectronic supplementary information (ESI) available: size distributions of samples modified with TOPO + PVP, HDA + PVP, and PVP only. See http://www.rsc.org/suppdata/jm/b3/b305526d/ , 2003 .

[33]  H. Hofmann,et al.  Superparamagnetic nanoparticles for biomedical applications: Possibilities and limitations of a new drug delivery system , 2005 .

[34]  M Dornish,et al.  Biomedical and pharmaceutical applications of alginate and chitosan. , 1999, Biotechnology & genetic engineering reviews.