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

• Published in: Journal of Chromatography A 2006-10, Vol.1130 (2), p.227-231
• Main Authors: Tsai, H.Y., Hsu, F.H., Lin, Y.P., Fuh, C. Bor
• Format: Article
• Language: English
• Subjects: Affinity; Analytical biochemistry: general aspects, technics, instrumentation; Analytical chemistry; Analytical, structural and metabolic biochemistry; Biological and medical sciences; Biotin - analysis; Biotin - metabolism; Chemistry; Chromatographic methods and physical methods associated with chromatography; Chromatography, Affinity - methods; Exact sciences and technology; Fundamental and applied biological sciences. Psychology; Immunoglobulin G - analysis; Immunoglobulin G - metabolism; Magnetics - instrumentation; Other chromatographic methods; Particle Size; Protein Binding; Reproducibility of Results; Staphylococcal Protein A - analysis; Staphylococcal Protein A - metabolism; Streptavidin - analysis; Streptavidin - metabolism
• ISSN: 0021-9673
• DOI: 10.1016/j.chroma.2006.05.045

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.