title: Evaluation of 2-methacryloyloxyethyl phosphorylcholine polymeric nanoparticle for immunoassay of C-reactive protein detection.
abstract: To prepare novel 2-methacryloyloxyethyl phosphorylcholine (MPC)-polymeric nanoparticle (MPC-PNP), water-soluble amphiphilic phospholipid polymer, poly [MPC-co-n-butyl methacrylate (BMA)-co-p-nitrophenyloxycarbonyl poly(ethylene glycol) methacrylate (MEONP) (PMBN)], which has active ester groups for bioconjugation on the side chains, was synthesized. MPC-PNP was prepared by a solvent evaporation technique where the poly(l-lactic acid) was used as core and PMBN was applied as an emulsifier and a surface modifier under systematical design of well-arranged phospholipids polar groups in its surface. Characteristics for MPC-PNP were thoroughly investigated with dynamic light scattering, electrophoresis light scattering, X-ray photoelectron spectroscopy, and field emission scanning electron microscopy measurements. Through a protein adsorption test, the phosphorylcholine group on the surface of MPC-PNPs, which had their active ester groups substituted by glycine, were shown to suppress the nonspecific adsorption of bovine serum albumin. These particles were used for C-reactive protein (CRP) detection, where anti-CRP monoclonal antibodies were immobilized on the MPC-PNP using the active ester group, while the remaining active ester groups were thoroughly reacted with glycine. The detection limit about serum-free CRP in the calibration curve was shown to extend from 0.01 to 10 mg/dL when anti-CRP antibody immobilized MPC-PNP was used for serum-free CRP detection. This compares favorably with measurement using polystyrene nanoparticles that were shown to detect from 0.1 to 10 mg/dL by an immunoagglutination technique. Also, for the detection of CRP in serum, MPC-PNP was shown to give the same calibration curve explained by the efficient suppression of nonspecific binding. Furthermore, denaturation of immobilizing anti-CRP antibody on the MPC-PNP hardly occurred despite increasing the temperature. It is concluded that MPC-PNP is unique due to the design of its interfacial properties, also it will perform well in a diagnostic immunoassay because of its optimized material properties.
authors.affiliation: Department of Materials Engineering, School of Engineering, The University of Tokyo, Tokyo, Japan.
authors.forename: Jongwon
authors.initials: J
authors.lastname: Park
authors.forename: Shigeru
authors.initials: S
authors.lastname: Kurosawa
authors.forename: Junji
authors.initials: J
authors.lastname: Watanabe
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Ishihara
mesh_terms: D000327:Adsorption; D000818:Animals; D002097:C-Reactive Protein / Q000032:analysis* / Q000737:chemistry; D002417:Cattle; D005069:Evaluation Studies as Topic; D007118:Immunoassay; D008689:Methacrylates / Q000032:analysis / Q000138:chemical synthesis / Q000737:chemistry*; D049329:Nanostructures / Q000032:analysis / Q000737:chemistry*; D010767:Phosphorylcholine / Q000031:analogs & derivatives* / Q000032:analysis / Q000138:chemical synthesis / Q000737:chemistry*; D011108:Polymers / Q000032:analysis / Q000138:chemical synthesis / Q000737:chemistry*
chemical_list: D008689:Methacrylates; D011108:Polymers; D010767:Phosphorylcholine; C070638:2-methacryloyloxyethyl phosphorylcholine; D002097:C-Reactive Protein