Separation method based on affinity reaction between magnetic and nonmagnetic particles for the analysis of particles and biomolecules.

H Y Tsai; F H Hsu; Y P Lin; C Bor Fuh

doi:10.1016/j.chroma.2006.05.045

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Separation method based on affinity reaction between magnetic and nonmagnetic particles for the analysis of particles and biomolecules.

H Y Tsai·F H Hsu·Y P Lin·C Bor Fuh

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Abstract

A separation method is reported for particle and biochemical analysis based on affinity interactions between particle surfaces under magnetic field. In this method, magnetic particles with immunoglobulin G (IgG) or streptavidin on the surface are flowed through a separation channel to form a deposition matrix for selectively capturing nonmagnetic analytes with protein A or biotin on the surface due to specific antigen (Ag)--antibody (Ab) interactions. This separation method was demonstrated using model reactions of IgG--protein A and streptavidin-biotin on particle surface. The features of this new separation method are (1) the deposited Ag-Ab complex can be examined and further analyzed under the microscope, (2) a kinetic study of complex binding is possible, and (3) the predeposited matrix can be formed selectively and changed easily. The detection limits were about 10(-11) g. The running time was less than 10 min. The selectivities of studied particles were 94% higher than those of label-controlled particles. This method extends the applications of analytical magnetapheresis to nonmagnetic particles. Preliminary study shows that this separation method has a great potential to provide a simple, fast, and selective analysis for particles, blood cells, and immunoassay related applications.

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Biotin Chromatography, Affinity Immunoglobulin G Magnetics Particle Size Protein Binding Reproducibility of Results Staphylococcal Protein A Streptavidin Journal Article Research Support, Non-U.S. Gov't

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H Y Tsai, F H Hsu, Y P Lin, C Bor Fuh. 2006-10-20. Separation method based on affinity reaction between magnetic and nonmagnetic particles for the analysis of particles and biomolecules.. https://doi.org/10.1016/j.chroma.2006.05.045

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