Magnetic particles applications

Katz E, Sheeney-Haj-lchia L, Basnar B, Felner 1, Willner I. Magnetoswitchable controlled hydrophilicity/hydrophobicity of electrode surfaces using alkyl-chain-functionaUzed magnetic particles application for switchable electrochemistry. Langmuir 2004 20 9714—9719. 

The great variety of inspection applications required the QAP system to perform relative measurements in judgeing certain conditions and not to restrict the user to dictated inspection conditions. One important example for MPI is for example the decision whether the magnetic particle suspension can be used or has to be changed. 

Particularly attractive for numerous bioanalytical applications are colloidal metal (e.g., gold) and semiconductor quantum dot nanoparticles. The conductivity and catalytic properties of such systems have been employed for developing electrochemical gas sensors, electrochemical sensors based on molecular- or polymer-functionalized nanoparticle sensing interfaces, and for the construction of different biosensors including enzyme-based electrodes, immunosensors, and DNA sensors. Advances in the application of molecular and biomolecular functionalized metal, semiconductor, and magnetic particles for electroanalytical and bio-electroanalytical applications have been reviewed by Katz et al. [142]. 

Gijs, M.A.M., Lacharme, F. and Lehmann, U. (2010) Microfluidic applications of magnetic particles for biological analysis and catalysis. Chemical Reviews, 110 (3), 1518-1563. 

Stripped magnetite particles. Applications of the double surfactant layer. Principle in the preparation of water based magnetic fluids. J. Colloid Interface Sci. 149 98-104 Wuehn, M, JosephJ., Bagus, P.S. Niklewski.A., Puettner, R., Reis,S., Weiss,W., Martins, M.,... 

A] As a result of applying a magnetic field, the poles of tiny magnetic particles in a magnetostrictive material line up, which alters the shape of the material. [B] The application of an electric field aligns particles in an electrorheological fluid. 

The so-called dry mixing or dry blending method has been used for the modification of" particles in the powder technology (59). In this method, surface modification of coarse particles is carried out by mixing fine particles and coarse particles with an auto ceramic mortar or with a centrifugal rotating mixer. This procedure can be applicable for the production of variety of composite magnetic particles. 

Equipment. From the applications standpoint, magnetic equipment falls into one of four broad categories tramp iron removal, magnetic particle separation and concentration, product cleaning, or eddy current separation on nonmagnetic metallics. 

By comparison with other NDC methods, such as liquid penetrant examination, magnetic particle, eddy current testing, and radiography, the ultrasonic method is the only technique that is applicable to a wide range of materials. 

As mentioned earlier, the immunoassay can be done with a number of procedural modifications and in this instance one must substitute the isotope with another molecule (fluorescent dye, magnetic particle, enzyme) which can be measured and therefore serve as the source of tracer. For our initial studies we have chosen to use the enzyme immunoassay (EIA) system. At the present time the EIA is still in its infancy and although a number of successful EIA s have been developed the method cannot be considered a panacea (34). The future of this assay appears to be very bright and exciting, and there is considerable interest in the application of the EIA to problems in both microbiology and clinical medicine (34). Many of the procedures and protocols are derived from RIA procedures and the EIA, like the RIA, has the potential to be performed in a multitude of procedural variations but, for the purpose of this manuscript we will describe only the system we have chosen for our use. 

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