title: Quantum dot FRET-based probes in thin films grown in microfluidic channels.
abstract: This paper describes the development of new fluorescence resonance energy transfer (FRET)-based quantum dot probes for proteolytic activity. The CdSe/ZnS quantum dots are incorporated into a thin polymeric film, which is prepared by layer-by-layer deposition of alternately charged polyelectrolytes. The quantum dots, which serve as fluorescent donors, are separated from rhodamine acceptor molecules, which are covalently attached to the film surface by a varying number of polyelectrolyte layers. When excited with visible light, the emission color of the polyelectrolyte multilayer film appears orange due to FRET between the quantum dots and molecular acceptors. The emission color changes to green when the rhodamine molecules are removed from the surface by enzymatic cleavage. The new probe design enables the use of quantum dots in bioassays, in this study for real-time monitoring of trypsin activity, while alleviating concerns about their potential toxicity. Application of these quantum dot FRET-based probes in microfluidic channels enables bioanalysis of volume-limited samples and single-cell studies in an in vivo-like environment.
authors.affiliation: Department of Chemistry and the Advanced Materials Research Institute, University of New Orleans, New Orleans, Louisiana 70148, USA.
authors.forename: Georgeta
authors.initials: G
authors.lastname: Crivat
authors.forename: Sandra Maria
authors.initials: SM
authors.lastname: Da Silva
authors.forename: Darwin R
authors.initials: DR
authors.lastname: Reyes
authors.forename: Laurie E
authors.initials: LE
authors.lastname: Locascio
authors.forename: Michael
authors.initials: M
authors.lastname: Gaitan
authors.forename: Nitsa
authors.initials: N
authors.lastname: Rosenzweig
authors.forename: Zeev
authors.initials: Z
authors.lastname: Rosenzweig
mesh_terms: D019187:Cadmium Compounds / Q000737:chemistry; D031541:Fluorescence Resonance Energy Transfer / Q000295:instrumentation / Q000379:methods*; D005456:Fluorescent Dyes / Q000737:chemistry; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation / Q000379:methods*; D045663:Quantum Dots; D012235:Rhodamines / Q000737:chemistry; D018036:Selenium Compounds / Q000737:chemistry; D013440:Sulfides / Q000737:chemistry; D014357:Trypsin / Q000032:analysis / Q000378:metabolism*; D017967:Zinc Compounds / Q000737:chemistry
chemical_list: D019187:Cadmium Compounds; D005456:Fluorescent Dyes; D012235:Rhodamines; D018036:Selenium Compounds; D013440:Sulfides; D017967:Zinc Compounds; C058667:cadmium selenide; D014357:Trypsin; C031238:zinc sulfide