title: Preparation, characterisation and application of europium(III) chelate-dyed polystyrene-acrylic acid nanoparticle labels.
abstract: Preparation, characterisation and application of europium(III) chelate-incorporated polystyrene-acrylic acid (AAc) nanoparticle labels featuring diverse AAc proportions is described. Emulsion copolymerisation of styrene and AAc was used to synthesise uniform-sized nanoparticles, approximately 50 nm in diameter. The structural, fluorescence and functional properties of the nanoparticles were characterised to obtain the optimal polymer composition of particulate labels. The AAc content had only a delicate effect on the fluorescence of the chelate and structural characteristics of the particles. The fluorescence spectra or lifetime of the incorporated europium(III) chelate were not notably affected, and all the particles were analogous in size, had monomodal size distributions and good colloidal stability. However, the AAc content affected strongly on the stability of the incorporated dye and functionality of the labels. Nanoparticles having up to 5.4 mass% of AAc were stable and applicable in high-sensitivity assays, where low detection limit and variation were achieved. The nanoparticles possessing 7.2 or 11.5 mass% of AAc lost remarkably the dye content during storage influencing their usability as labels in assays. Overall, the characterisation and employment results achieved evidenced the importance of the structural composition of nanoparticles, moreover, the knowledge of the effects of structural changes is utilisable in the development of improved nanoparticle labels and assay applications.
authors.affiliation: Department of Biotechnology, University of Turku, Turku, Finland.
authors.forename: Petri
authors.initials: P
authors.lastname: Huhtinen
authors.forename: Mirja
authors.initials: M
authors.lastname: Kivelä
authors.forename: Tero
authors.initials: T
authors.lastname: Soukka
authors.forename: Heikki
authors.initials: H
authors.lastname: Tenhu
authors.forename: Timo
authors.initials: T
authors.lastname: Lövgren
authors.forename: Harri
authors.initials: H
authors.lastname: Härmä
mesh_terms: D000179:Acrylates / Q000138:chemical synthesis* / Q000737:chemistry; D002614:Chelating Agents / Q000737:chemistry; D005063:Europium / Q000737:chemistry*; D005453:Fluorescence; D005456:Fluorescent Dyes / Q000737:chemistry; D007118:Immunoassay / Q000379:methods; D053758:Nanoparticles / Q000737:chemistry*; D011137:Polystyrenes / Q000138:chemical synthesis* / Q000737:chemistry; D017430:Prostate-Specific Antigen / Q000032:analysis
chemical_list: D000179:Acrylates; D002614:Chelating Agents; D005456:Fluorescent Dyes; D011137:Polystyrenes; D005063:Europium; D017430:Prostate-Specific Antigen; C036658:acrylic acid