Improvement of accuracy in flow immunosensor system by introduction of poly -2-[3-(methacryloylamino)propylammonio]ethyl 3-aminopropyl phosphate

In order to improve the accuracy of immunosensor systems,poly-2-[3-(methacryloylamino)propylammonio]ethyl 3-aminopropyl phosphate (poly-3mam3ap),which includes both phosphorylcholine and amino groups,was synthesized and applied to the preparation of antibody-immobilized beads. acting as an antibody-immobilizing material,poly-3mam3ap is expected to significantly lower nonspecific adsorption due to the presence of the phosphorylcholine group and recognize large numbers of analytes due to the increase in antibody-immobilizing sites. the elimination of nonspecific adsorption was compared between the formation of a blocking layer on antibody-immobilized beads and the introduction of a material to combine antibody with beads. determination with specific and nonspecific antibodies was then investigated for the estimation of signal-to-noise ratio. signal intensities with superior signal-to-noise ratios were obtained when poly-3mam3ap was introduced. this may be due to the increase in antibody-immobilizing sites and the extended space for antigen-antibody interaction resulting from the electrostatic repulsion of poly-3mam3ap. thus,the application of poly-3mam3ap coatings to immunoassay beads was able to improve the accuracy of flow immunosensor systems. copyright © 2011 yusuke fuchiwaki et al.