Magnetic micro-beads

Magnetic Micro-bead Mixing Most Relevant Citations... 

Mixer 23 [M 23] Magnetic Micro-bead Micro Mixer... 

This magnetic micro-bead mixer relies on a dynamic mixing principle, based on stirring of externally driven small particles in a small mixing chamber [106,107]. Magnetic beads made of nickel were enclosed in this chamber. The externally stimulated bead motion resulted in rapid homogenization of the solutions to be mixed. 

Micro-SMB separators have only been studied numerically (Subramani and Kurup, 2006), but one can think of ways to implement a real moving bed in a miniaturized version by applying a shifting magnetic field on, for example, magnetic resin beads or applying DEP on adsorbent particles, in a microchannel. 

Magnetic micro- and nanogel beads containing magnetic nanoparticles were also prepared and studied. 

Micro- and nanobeads with magnetic properties have recently become popular since these tools can be manipulated, e.g., collected in the region of interest. Magnetite nanoparticles are introduced in order to render the polymeric beads magnetic. Preparation and application of magnetic beads will be discussed in more detail in Sect 5.5. 

Solid phase Using antibodies coupled to plastic tubes, beads, micro-plates Using antibodies coupled to magnetic particles... 

A biological application, bacteria capture by mixing of blood/bacteria samples with magnetic beads, was carried out in the L-shaped micro mixer [49], A high capture efficiency of 99% was obtained at a short time of 0.15 s. The blood cells and bacteria remained intact after the mixing process, evidencing the low shear strain field of the flow. 

Desalting by reversed-phase HPLC (see Subheading 2.4.) or SEC or micro-SPE onto Ci 8 Zip-Tip (used the conditions recommended by the manufacturer Millipore). The recently developed magnetic beads from Bruker may represent a fast and economical alternative. 

Micro- and nano-beads have become a major tool in analytical chemistry sciences. On one hand, micrometer size beads were developed with a very large range of properties such as magnetic and/or fluorescent beads, having different surface functional groups for coupling chemistry or physicochemical properties. On the other hand, few nanometer size particles were shown to be potential powerful labels for on chip detection of DNA strands. 

Matsunaga T, Maeda Y, Yoshino T et al (2007) FuUy automated immunoassay for detection of prostate-specific antigen using nano-magnetic beads and micro-polystyrene bead composites, Beads on Beads . Anal Chim Acta 597 331-339... 

F. Lacharme, C. Vandevyver, and M.A.M. Gijs Magnetic bead retention device for full on-chip sandwich immuno-assay. in 21st IEEE International Conference on Micro Electro Mechanical Systems MEMS 2008, 184-187 (2008) Tucson, AZ, USA. 

Derks RJS, Dietzel A, Wimberger-Friedl R, PrinsMWJ et aL (2007) Magnetic bead manipulation in a sub-microliter fluid volume applicable for biosensing. Micro. Nano. 3 141—149. 

S. Laschi, 1. Palchetti, G. Marrazza, and M. Mascini, Enzyme-amplified electrochemical hybridization assay based on PNA, LNA and DNA probe-modified micro-magnetic beads. Bioelectrochemistry 76(1-2], 214-220 (2009]. 

Magnetic Field-Based Lab-on-Chip Devices, Fig. 4 Example of magnetic field-based micro-immunoassay (Fig. based on [8]). (a) Molecules successively attached to the beads Grafting of the first antibody, antigen attached to this antibody, second labeled antibody attached to the antigen, (b) Magnets on the side of the channel and complete setup for observation, (c) At a relative slow flow rate, molecule can diffuse to the beads... 

By using the micro/nanoparticles and magnetic beads, the homogenous immimoassay without the separation of whole blood can be manipulated. However, the detection sensitivity is limited due to the complex whole blood enviromnent. For the heterogeneous immunoassay, the commercial... 

Bayerl, T. M., and Bloom, M. 1990. Physical properties of single phospholipid bilayers adsorbed to micro glass beads. A new vesicular model system studied by deuterium nuclear magnetic resonance. Biophys. J. 58 357. 

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