title: Phosphate sensing by fluorescent reporter proteins embedded in polyacrylamide nanoparticles.
abstract: Phosphate sensors were developed by embedding fluorescent reporter proteins (FLIPPi) in polyacrylamide nanoparticles with diameters from 40 to 120 nm. The sensor activity and protein loading efficiency varied according to nanoparticle composition, that is, the total monomer content (% T) and the cross-linker content (% C). Nanoparticles with 28% T and 20% C were considered optimal as a result of relatively high loading efficiency (50.6%) as well as high protein activity (50%). The experimental results prove that the cross-linked polyacrylamide matrix could protect FLIPPi from degradation by soluble proteases to some extent. This nanoparticle embedding method provides a novel promising tool for in vivo metabolite studies. It also demonstrates a universal method for embedding different fragile bioactive elements, such as antibodies, genes, enzymes, and other functional proteins, in nanoparticles for, for example, sensing, biological catalysis, and gene delivery.
authors.affiliation: Polymer Department, Risø, Technical University of Denmark, Roskilde 4000, Denmark. honghaosuncn@gmail.com
authors.forename: Honghao
authors.initials: H
authors.lastname: Sun
authors.forename: Anne Marie
authors.initials: AM
authors.lastname: Scharff-Poulsen
authors.forename: Hong
authors.initials: H
authors.lastname: Gu
authors.forename: Iver
authors.initials: I
authors.lastname: Jakobsen
authors.forename: Jens M
authors.initials: JM
authors.lastname: Kossmann
authors.forename: Wolf B
authors.initials: WB
authors.lastname: Frommer
authors.forename: Kristoffer
authors.initials: K
authors.lastname: Almdal
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry*; D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods*; D003432:Cross-Linking Reagents / Q000737:chemistry; D004926:Escherichia coli / Q000235:genetics; D008164:Luminescent Proteins / Q000096:biosynthesis / Q000737:chemistry* / Q000378:metabolism*; D053758:Nanoparticles / Q000737:chemistry*; D010316:Particle Size; D010447:Peptide Hydrolases / Q000737:chemistry / Q000378:metabolism; D010710:Phosphates / Q000032:analysis*; D012995:Solubility; D013050:Spectrometry, Fluorescence; D000099166:Polyacrylamides
chemical_list: D000180:Acrylic Resins; D003432:Cross-Linking Reagents; D008164:Luminescent Proteins; D010447:Peptide Hydrolases; D010710:Phosphates; D000099166:Polyacrylamides