Flow immunosensing system utilizing antibodies immobilized on beads coated with poly-2-[3-(methacryloylamino)propylammonio]ethyl 3-aminopropyl phosphate

In order to increase the signal-to-noise ratio of immunosensors, a flow immunosensing system was fabricated containing poly-2-[3-(methacryloylamino)propylammonio]ethyl 3-aminopropyl phosphate (poly-3MAm3AP) at the antigen–antibody reacted interface. Poly-3MAm3AP is a polymer containing phosphorylcholine groups (which act to attract water) and amino groups (useful for the covalent attachment of receptors). Anti-luteinizing hormone (LH) antibody-immobilized beads coated with poly-3MAm3AP were prepared and packed into the reactor column of a flow immunosensing system. Nonspecific anti-hemoglobin antibodies were also used in order to estimate the level of nonspecific adsorption. The fabricated immunosensing system not only significantly reduced nonspecific adsorption, but also detected signal intensity with superior signal-to-noise, thus demonstrating the potential of this approach for the commercialization of immunosensing technologies.

► Poly-2-[3-(methacryloylamino)propylammonio]ethyl 3-aminopropyl phosphate (poly-3MAm3AP) was introduced at the antigen–antibody reacted interface and increased the signal-to-noise ratio of immunosensors. ► Poly-3MAm3AP is a polymer containing phosphorylcholine groups and amino group. ► The fabricated immunosensing system not only significantly reduced nonspecific adsorption, but also detected signal intensity with superior signal-to-noise.