title: Visual and fluorescent detection of tyrosinase activity by using a dual-emission ratiometric fluorescence probe.
abstract: In this work, we designed a dual-emission ratiometric fluorescence probe by hybridizing two differently colored quantum dots (QDs), which possess a built-in correction that eliminates the environmental effects and increases sensor accuracy. Red emissive QDs were embedded in the silica nanoparticle as reference while the green emissive QDs were covalently linked to the silica nanoparticle surface to form ratiometric fluorescence probes (RF-QDs). Dopamine (DA) was then conjugated to the surface of RF-QDs via covalent bonding. The ratiometric fluorescence probe functionalized with dopamine (DA) was highly reactive toward tyrosinase (TYR), which can catalyze the oxidization of DA to dopamine quinine and therefore quenched the fluorescence of the green QDs on the surface of ratiometric fluorescence probe. With the addition of different amounts of TYR, the ratiometric fluorescence intensity of the probe continually varied, leading to color changes from yellow-green to red. So the ratiometric fluorescence probe could be utilized for sensitive and selective detection of TYR activity. There was a good linear relationship between the ratiometric fluorescence intensity and TYR concentration in the range of 0.05-5.0 μg mL(-1), with the detection limit of 0.02 μg mL(-1). Significantly, the ratiometric fluorescence probe has been used to fabricate paper-based test strips for visual detection of TYR activity, which validates the potential on-site application.
authors.affiliation: Department of Analytical Chemistry, College of Chemistry, Jilin University , Changchun, 130012, P.R. China.
authors.forename: Xu
authors.initials: X
authors.lastname: Yan
authors.affiliation: School of Pharmacy, Jilin University , Changchun 130021, P.R. China.
authors.forename: Hongxia
authors.initials: H
authors.lastname: Li
authors.affiliation: State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University , Changchun 130012, P.R. China.
authors.forename: Weishi
authors.initials: W
authors.lastname: Zheng
authors.affiliation: Department of Analytical Chemistry, College of Chemistry, Jilin University , Changchun, 130012, P.R. China.
authors.forename: Xingguang
authors.initials: X
authors.lastname: Su
mesh_terms: D004789:Enzyme Activation; D057075:Enzyme Assays / Q000379:methods*; D005453:Fluorescence; D005456:Fluorescent Dyes / Q000737:chemistry*; D015394:Molecular Structure; D014442:Monophenol Monooxygenase / Q000032:analysis* / Q000378:metabolism*; D053758:Nanoparticles / Q000737:chemistry; D045663:Quantum Dots; D012822:Silicon Dioxide / Q000737:chemistry; D013050:Spectrometry, Fluorescence / Q000295:instrumentation
chemical_list: D005456:Fluorescent Dyes; D012822:Silicon Dioxide; D014442:Monophenol Monooxygenase