title: Preparation of cross-linked, multilayer-coated fluorescent microspheres with functional groups on the surface for bioconjugation.
abstract: This study is to develop a method for preparing fluorescent microspheres with steady and strong fluorescence as well as the surface functionality for bioconjugation. Layer-by-layer technique was employed to introduce poly(phenylenevinylene) (PPV) precursor, diazoresin (DAR), and polyanion, including poly(acrylic acid) (PAA) and poly(sodium-p-styrenesulfonate) (PSS), onto the substrate polystyrene-divinylbenzene microspheres with sulfonic groups on the surface (SPSDVB). The conversion of PPV precursor into fluorescent PPV as well as the cross-linking reaction between DAR and polyanion, were accomplished simultaneously in the following thermal treatment. After optimizing the DAR concentration, the selection of polyelectrolytes and the coating sequence, the cross-linked multilayer coated PPV microspheres, SPSDVB-(PPV/PSS/DAR/PAA) spheres, were prepared. These spheres were found to have uniform size with a clear core-shell structure and display even and strong fluorescence, based on the characterization by flow cytometry, microscopy, and photophysics. They were found to be stable and highly resistant to common solvents and even "dissociation agent", as well as possess good thermal stability and photostability. The feasibility of conjugating biomolecules on the surface of spheres was also demonstrated.
authors.affiliation: Suzhou Key Laboratory of Macromolecular Design and Precision Synthesis, Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application, Department of Polymer Science and Engineering, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, P. R. China.
authors.forename: Tian
authors.initials: T
authors.lastname: Qiu
authors.affiliation: Suzhou Key Laboratory of Macromolecular Design and Precision Synthesis, Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application, Department of Polymer Science and Engineering, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, P. R. China.
authors.forename: Yun
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Suzhou Key Laboratory of Macromolecular Design and Precision Synthesis, Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application, Department of Polymer Science and Engineering, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, P. R. China.
authors.forename: Jing
authors.initials: J
authors.lastname: Song
authors.affiliation: Suzhou Key Laboratory of Macromolecular Design and Precision Synthesis, Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application, Department of Polymer Science and Engineering, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, P. R. China.
authors.forename: Li-Juan
authors.initials: LJ
authors.lastname: Fan
mesh_terms: D001391:Azo Compounds / Q000737:chemistry*; D001704:Biopolymers / Q000032:analysis / Q000737:chemistry*; D020099:Coated Materials, Biocompatible / Q000138:chemical synthesis*; D003432:Cross-Linking Reagents / Q000737:chemistry; D005456:Fluorescent Dyes / Q000138:chemical synthesis*; D008422:Materials Testing; D008863:Microspheres; D011108:Polymers / Q000737:chemistry*; D013050:Spectrometry, Fluorescence / Q000379:methods; D013499:Surface Properties
chemical_list: D001391:Azo Compounds; D001704:Biopolymers; D020099:Coated Materials, Biocompatible; D003432:Cross-Linking Reagents; D005456:Fluorescent Dyes; D011108:Polymers; C504851:diazoresin
keywords: bioconjugation; cross-linking; flow cytometry; fluorescent microsphere; layer-by-layer