A sensitive polymer dots-manganese dioxide fluorescent nanosensor for “turn-on” detection of glutathione in human serum

Song

ACS Appl. Mater. Interfaces

et al. 2018

Bimodal fluorescence-magnetic resonance imaging (MRI) technique has shown great utilities in bioassays because it combines the advantages of both optical imaging and MRI to provide more sufficient information over any modality alone. In this work, on the basis of a MnO nanosheet-Ru(II) complex nanoarchitecture, a bimodal phosphorescence-MRI nanoprobe for glutathione (GSH) has been constructed. The nanoprobe, Ru(BPY)@MnO, was constructed by integrating MnO nanosheets with a phosphorescent Ru(II) complex [Ru(BPY)](PF) (BPY = 2,2'-bipyridine), which resulted in complete phosphorescence quenching of the Ru(II) complex, accompanied by very low longitudinal and transverse relaxivity. Upon exposure to GSH, the reduction of MnO nanosheets by GSH triggers a recovery of phosphorescence and simultaneously produces a number of Mn ions, a perfect MRI contrast agent. The as-prepared nanoprobe showed good water dispersion and biocompatibility and a rapid, selective, and sensitive response toward GSH in the phosphorescence and MR detection modes. The practicability of the nanoprobe was proved by time-gated luminescence assay of GSH in human serum, phosphorescent imaging of endogenous GSH in living cells, zebrafish, and tumor-bearing mice, as well as the MRI of GSH in tumor-bearing mice. The research outcomes suggested the potential of Ru(BPY)@MnO for the bimodal phosphorescence-MRI sensing of GSH in vitro and in vivo.

Section: Resultssupporting

confidence: 81%

Section: ■ Experimental Sectionmentioning

confidence: 94%

Bimodal Phosphorescence–Magnetic Resonance Imaging Nanoprobes for Glutathione Based on MnO₂ Nanosheet–Ru(II) Complex Nanoarchitecture

Song

ACS Appl. Mater. Interfaces

et al. 2018

ACS Appl. Mater. Interfaces

“…Generally, the fluorescence lifetime of a fluorophore decreases during fluorescence resonance energy transfer (FRET) because of energy transfer from the fluorophore to the quencher, while the fluorescence lifetime is invariable for IFE. , As seen from Figure C and Table S1, the fluorescence lifetimes of g-C 3 N 4 show a slight change after adding different concentrations of TC, which indicates that the TC-induced fluorescence quenching of g-C 3 N 4 primarily results from the IFE rather than FRET. To further evaluate the role of IFE in fluorescence quenching, a related correction was performed using Equation S1. − Figure S8 and Table S2 show the relevant corrected data and results. The fluorescence quenching efficiency of TC toward g-C 3 N 4 before and after correction is shown in Figure D.…”

Section: Resultsmentioning

confidence: 99%

Smartphones and Test Paper-Assisted Ratiometric Fluorescent Sensors for Semi-Quantitative and Visual Assay of Tetracycline Based on the Target-Induced Synergistic Effect of Antenna Effect and Inner Filter Effect

Han

Fan

Qing

et al. 2020

Self Cite

121

Development of selective and sensitive methods for on-site assay of tetracycline (TC) is of great significance for public health and food safety. Herein, a valid ratiometric fluorescence strategy using g-C 3 N 4 nanosheets coupled with Eu 3+ is designed for the assay of TC. In this strategy, both Eu 3+ and g-C 3 N 4 nanosheets serve as the recognition units of TC. The blue fluorescence of g-C 3 N 4 nanosheets can be quenched by TC via the inner filter effect (IFE); meanwhile, the red fluorescence of Eu 3+ can be enhanced by TC through the antenna effect (AE). The synergistic effect of AE and IFE caused by TC makes the developed ratiometric fluorescent sensor display a wide linear range for TC from 0.25 to 80 μM with a detection limit of 6.5 nM and a significant fluorescence color evolution from blue to red. Given its simplicity, free-label, excellent selectivity, high sensitivity, and recognizable color change, point-of-care testing systems, including smartphones and test paper-based assays, are developed for the visual sensing of TC. The integration of smartphones and test paper on a ratiometric fluorescent sensor greatly reduces the detection cost and time, providing a promising method for the qualitative discernment and semi-quantitative assay of TC on-site. Moreover, the potential application of the approach is also verified by detecting TC in milk.

“…Conceptually, 50% or more semiconducting polymer (by volume or weight) is important because it distinguishes Pdots as NPs derived from a photoluminescent material rather than a doped host polymer. That said, there are also examples where “Pdot” refers to luminescent NPs composed of non-semiconducting polymer materials where PL arises from cross-link-enhanced emission, − aggregation-induced emission (AIE) Pdots (or AIE dots), , or pendent fluorophores …”

Section: Catalog Of Materialsmentioning

confidence: 99%

Photoluminescent Nanoparticles for Chemical and Biological Analysis and Imaging

et al. 2021

Research related to the development and application of luminescent nanoparticles (LNPs) for chemical and biological analysis and imaging is flourishing. Novel materials and new applications continue to be reported after two decades of research. This review provides a comprehensive and heuristic overview of this field. It is targeted to both newcomers and experts who are interested in a critical assessment of LNP materials, their properties, strengths and weaknesses, and prospective applications. Numerous LNP materials are cataloged by fundamental descriptions of their chemical identities and physical morphology, quantitative photoluminescence (PL) properties, PL mechanisms, and surface chemistry. These materials include various semiconductor quantum dots, carbon nanotubes, graphene derivatives, carbon dots, nanodiamonds, luminescent metal nanoclusters, lanthanidedoped upconversion nanoparticles and downshifting nanoparticles, triplet−triplet annihilation nanoparticles, persistent-luminescence nanoparticles, conjugated polymer nanoparticles and semiconducting polymer dots, multi-nanoparticle assemblies, and doped and labeled nanoparticles, including but not limited to those based on polymers and silica. As an exercise in the critical assessment of LNP properties, these materials are ranked by several application-related functional criteria. Additional sections highlight recent examples of advances in chemical and biological analysis, point-of-care diagnostics, and cellular, tissue, and in vivo imaging and theranostics. These examples are drawn from the recent literature and organized by both LNP material and the particular properties that are leveraged to an advantage. Finally, a perspective on what comes next for the field is offered.