title: Near-infrared-emitting nanoparticles for lifetime-based multiplexed analysis and imaging of living cells.
abstract: The increase in information content from bioassays and bioimaging requires robust and efficient strategies for the detection of multiple analytes or targets in a single measurement, thereby addressing current health and security concerns. For fluorescence techniques, an attractive alternative to commonly performed spectral or color multiplexing presents lifetime multiplexing and the discrimination between different fluorophores based on their fluorescence decay kinetics. This strategy relies on fluorescent labels with sufficiently different lifetimes that are excitable at the same wavelength and detectable within the same spectral window. Here, we report on lifetime multiplexing and discrimination with a set of nanometer-sized particles loaded with near-infrared emissive organic fluorophores chosen to display very similar absorption and emission spectra, yet different fluorescence decay kinetics in suspension. Furthermore, as a first proof-of-concept, we describe bioimaging studies with 3T3 fibroblasts and J774 macrophages, incubated with mixtures of these reporters employing fluorescence lifetime imaging microscopy. These proof-of-concept measurements underline the potential of fluorescent nanoparticle reporters in fluorescence lifetime multiplexing, barcoding, and imaging for cellular studies, cell-based assays, and molecular imaging.
authors.affiliation: BAM Federal Institute for Materials Research and Testing, Richard-Willstaetter-Straße 11, 12489 Berlin, Germany.
authors.forename: Katrin
authors.initials: K
authors.lastname: Hoffmann
authors.forename: Thomas
authors.initials: T
authors.lastname: Behnke
authors.forename: Daniela
authors.initials: D
authors.lastname: Drescher
authors.forename: Janina
authors.initials: J
authors.lastname: Kneipp
authors.forename: Ute
authors.initials: U
authors.lastname: Resch-Genger
mesh_terms: D016475:3T3 Cells; D000042:Absorption; D000818:Animals; D001681:Biological Assay; D002460:Cell Line; D018920:Coculture Techniques; D003470:Culture Media / Q000737:chemistry; D005347:Fibroblasts / Q000378:metabolism; D005456:Fluorescent Dyes / Q000737:chemistry; D007700:Kinetics; D008264:Macrophages / Q000166:cytology / Q000378:metabolism; D051379:Mice; D018613:Microscopy, Confocal; D008856:Microscopy, Fluorescence; D057054:Molecular Imaging; D053758:Nanoparticles / Q000737:chemistry*; D036103:Nanotechnology / Q000379:methods*; D013053:Spectrophotometry; D019265:Spectroscopy, Near-Infrared / Q000379:methods*
chemical_list: D003470:Culture Media; D005456:Fluorescent Dyes