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Ag@SiO2 core–shell nanoparticles (NPs) have attracted extensive attention for their excellent surface-enhanced Raman scattering (SERS)-fluorescence (SEF) and their potential applications in sensing, biomedicine, and imaging. The thickness of silica shell plays a crucial role in determining the SERS-SEF properties. However, a few studies have been made to synthesize Ag@SiO2 core–shell NPs with controllable thickness of silica shell and systematic research about the optimized SERS-SEF enhancement. Here, Ag@SiO2 core–shell NPs were prepared by a modified one-pot synthetic method via reducing AgNO3 using formaldehyde in the presence of cetyltrimethylammonium chloride and sequentially hydrolyzing tetraethyl orthosilicate (TEOS). The effects of the type of surfactant and the concentrations of NaOH and AgNO3 on the size and morphology of the resulting Ag@SiO2 core–shell NPs were systematically investigated. The thickness of the silica shell could be finely tuned from 9.3 to 38.9 nm by easily adjusting the amount of TEOS. The crystal violet molecule was used for examining SERS and SEF properties of Ag@SiO2 core–shell NPs with different SiO2 thicknesses. The current work will provide guidance for further understanding the growth mechanism of Ag@SiO2 core–shell NPs and how the thickness of silica shell affects the SERS-SEF properties. [ABSTRACT FROM AUTHOR]

Different source arrangements can significantly affect the material distribution within emitting layers of OLEDs. By optimizing the source arrangement, increasing the concentration of the assisted phosphor, and decreasing the concentration of the multi‐resonance fluorescent dopant at the interface, the efficiency of phosphor‐assisted fluorescence device can be enhanced by 14%. [ABSTRACT FROM AUTHOR]

Different source arrangements can significantly affect the material distribution within emitting layers of OLEDs. By optimizing the source arrangement, increasing the concentration of the assisted phosphor, and decreasing the concentration of the multi‐resonance fluorescent dopant at the interface, the efficiency of phosphor‐assisted fluorescence device can be enhanced by 14%. [ABSTRACT FROM AUTHOR]

MiR-451a is a biomolecule tightly related to resistance development during treatment with selective estrogen-receptor modulators for breast cancer. Accurately and sensitively monitoring its level in cells is of great significance for the drug selection and the evaluation of this cancer. However, the commonly obtainable ssDNA probe cannot efficiently enter the cell to sensitively emit reliable signals by avoiding nuclease digestion. Herein, a sensing system is reported to monitor miR-451a in living cells with high specificity and sensitivity. The system consisted of reduced graphene oxide (rGO), duplex-specific nuclease (DSN), and a fluorescence-labeled ssDNA nanoprobe. The fluorescence probe on the rGO surface provided an ultra-low background and resistance to endonuclease digestion. Duplex-specific nuclease sequentially triggered the hybridization cycle and the cleavage of ssDNA nanoprobe. The signal amplification provided a detection limit of 1 fM miR-451a using the optimal conditions with a linear range from 1 fM to 100 nM. Finally, the developed method was used to determine miR-451a in breast cancer tissue. This strategy provides a promising tool for clinical diagnosis and evaluation of miR-451a related cancer. [ABSTRACT FROM AUTHOR]

Near-infrared luminophores have many advantages in advanced applications, especially for structures without π-conjugation aromatic rings. However, the fabrication of red clusteroluminogens from nonconjugated polymers is still a big challenge, let alone the near-infrared clusteroluminogens. Here, we develop nonconjugated luminophores with full-spectrum from blue to near-infrared light (470 ~ 780 nm), based on color phenomenon of nonconjugated polyesters synthesized from the amine-initiated copolymerization of epoxides and cyclic anhydrides. We reveal that amines act as initiators attached to polymer chain ends. The formation of various amine-ester complexes in polyesters induces red to near-infrared light, conceptually, amine-ester complexed clusteroluminescence via intra/inter-chain charge transfer. Significantly, emission colors can be easily tuned by the contents and types of amines, microstructures of polyesters, and their concentration. This work provides a low-cost, scalable platform and strategy for the production of high-efficiency, multicolor luminescent materials. Near-infrared luminescence is useful for advance applications, but is challenging to achieve through clusteroluminescence. Here, the authors report the use of amine-initiated polyesters for amine-ester clusters with near-infrared emission. [ABSTRACT FROM AUTHOR]

Intermolecular proton transfer from a flavonol-based probe to the arginine (Arg222) in drug site 1 of human serum albumin triggers an unusual red-shifted ratiometric fluorescence response, which can be applied in the point-to-care diagnosis of hypoalbuminemia. [ABSTRACT FROM AUTHOR]

Two structurally similar columnar ZnII-MOFs {[Zn8L4(TZ)4·0.5H2O]·4[Me2NH2]·6DMF·4H2O}n (Zn-MOF1) and {[Zn4L2(MT)2·H2O]·2[Me2NH2]·4DMF·4H2O}n (Zn-MOF2) were synthesized with irregular ligands, 2,2′-(pyridine-2,6-diyl) diterephthalic acid (H4L), 1,2,4-triazolium (TZ) and 1H-1,2,4-triazole-3-thiol (MT). Structural studies showed that both ZnII-MOFs had a similar 3D framework constructed with multiple SBUs and displayed an unusual (3,4,6)-connection topology. Furthermore, both ZnII-MOFs have high performance in gas adsorption and separation. The separation ratios of C2H2/CH4 and CO2/CH4 of Zn-MOF1 were 15.1 and 6.8, respectively, and those of Zn-MOF2 were 14.6 and 6.5, respectively. Moreover, Eu@Zn-MOF1 and Eu@Zn-MOF2 were successfully obtained by adding Eu3+ ions to the synthesis system. After a series of fluorescence tests, these two MOFs were found to have good fluorescence performance, and showed high selectivity and sensitivity to Fe3+ ions in aqueous solution with a low detection limit. [ABSTRACT FROM AUTHOR]

Over-expression of glutathione S-transferase (GST) can promote Cisplatin resistance in hepatocellular carcinoma (HCC) treatment. Hence, inhibiting GST is an attractive strategy to improve Cisplatin sensitivity in HCC therapy. Although several synthesized GST inhibitors have been developed, the side effects and narrow spectrum for anticancer seriously limit their clinical application. Considering the abundance of natural compounds with anticancer activity, this study developed a rapid fluorescence technique to screen "green" natural GST inhibitors with high specificity. The fluorescence assay demonstrated that schisanlactone B (hereafter abbreviated as C1) isolated from Xue tong significantly down-regulated GST levels in Cisplatin-resistant HCC cells in vitro and in vivo. Importantly, C1 can selectively kill HCC cells from normal liver cells, effectively improving the therapeutic effect of Cisplatin on HCC mice by down-regulating GST expression. Considering the high GST levels in HCC patients, this compound demonstrated the high potential for sensitizing HCC therapy in clinical practice by down-regulating GST levels. [Display omitted] • Designed a visual fluorescent probe PM for the rapid screening GST natural inhibitors. • The natural and "green" GST inhibitor C1 showed high safety to normal liver cells but high toxicity to HCC cells. • The inhibitor C1 demonstrated an excellent sensitizing effect on Cisplatin-resistant and sensitive HCC. [ABSTRACT FROM AUTHOR]

Au/Ag alloy@SiO2 core–shell nanoparticles (Au/Ag@SiO2 CSNs) can be applied in fields of catalysis and biosensor, because of the advantages, such as high stability, good biocompatibility, and tunable plasmonic properties. However, a few studies have been made to synthesize Au/Ag@SiO2 CSNs. There is no systematic research about the dependence of metal-enhanced fluorescence (MEF) and surface-enhanced Raman scattering (SERS) enhancement on the composition of Au/Ag@SiO2 CSNs. Here, we successfully prepared Au/Ag@SiO2 CSNs with various Au to Ag molar ratios using a facile one-pot approach. We systematically investigated the influence of the composition of Au/Ag@SiO2 CSNs on their MEF and SERS properties using crystal violet (CV) as fluorescence and Raman molecule. The MEF and SERS enhancement improves as the Ag proportion in Au/Ag@SiO2 CSNs increases. The current research provides a facile method to fabricate Au/Ag@SiO2 CSNs and promotes their potential applications in MEF-SERS dual-mode detection and imaging. [ABSTRACT FROM AUTHOR]

The precise identification of wood plays a vital role in protecting rare timber species. Among the various wood identification techniques, the fluorescence characteristics of Pterocarpus santalinus L.f. species have rarely been investigated. In this study, the types, number of fluorescent compounds, maximum excitation and emission wavelengths, and effects of solvent and pH were characterized by fluorescence photographs, fluorescence emission spectra and fluorescence contour spectra, respectively. The results indicate that the fluorescence of P. santalinus species is relatively strong, and the fluorescent substances extracted in different solvents exhibit different color photographs under irradiation. The spectrum is also affected by the polarity of the solvent and the pH of the solution. In addition, the method for extracting the fluorescent compounds in P. santalinus samples was optimized. Based on the reported results, a good correlation between the fluorescence characteristics and the wood species was obtained as a potentially new identification method for precious rosewoods at the species level. [ABSTRACT FROM AUTHOR]

[Display omitted] • A new series of dicyanoisophorone fluorophores with different donor groups have been synthesized and their photophysical properties have been studied. • The fluorescent probe with p -dimethylamine and o -hydroxyl group exhibited the best sensing ability to human serum albumin. • The sensing mechanism was studied by Job's plot, replacement experiment, and molecular docking. • The fluorescent probe is capable of determination of albumin in real serum and urine samples. It is urgently needed to develop NIR-fluorescent probe for detection of human serum albumin (HSA) since the interference of short-wavelength-fluorescence from endogenous species in real serum and urine. However, most previous reports were located in the short-wavelength region (<600 nm). In this work, a series of dicyanoisophorone (DCO)-based fluorophores 1 – 4 with different donor groups have been designed and investigated. A systematic study of their photophysical properties has been carried out. Among these probes, 4 exhibited NIR emission with the highest fluorescence brightness and the most sensitive signal response to HSA. Further studies demonstrated that 4 could strongly bind into the DS1 pocket of HSA with a 1:1 ratio. Importantly, the method based on 4 has been proven to be capable of sensing HSA in real serum and urine samples. [ABSTRACT FROM AUTHOR]

Two structurally similar columnar ZnII-MOFs {[Zn8L4(TZ)4·0.5H2O]·4[Me2NH2]·6DMF·4H2O}n (Zn-MOF1) and {[Zn4L2(MT)2·H2O]·2[Me2NH2]·4DMF·4H2O}n (Zn-MOF2) were synthesized with irregular ligands, 2,2′-(pyridine-2,6-diyl) diterephthalic acid (H4L), 1,2,4-triazolium (TZ) and 1H-1,2,4-triazole-3-thiol (MT). Structural studies showed that both ZnII-MOFs had a similar 3D framework constructed with multiple SBUs and displayed an unusual (3,4,6)-connection topology. Furthermore, both ZnII-MOFs have high performance in gas adsorption and separation. The separation ratios of C2H2/CH4 and CO2/CH4 of Zn-MOF1 were 15.1 and 6.8, respectively, and those of Zn-MOF2 were 14.6 and 6.5, respectively. Moreover, Eu@Zn-MOF1 and Eu@Zn-MOF2 were successfully obtained by adding Eu3+ ions to the synthesis system. After a series of fluorescence tests, these two MOFs were found to have good fluorescence performance, and showed high selectivity and sensitivity to Fe3+ ions in aqueous solution with a low detection limit. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel flavonoid probe is reported for fluorescence discrimination of HSA from BSA. • The sensing mechanism was studied by Job's plot, site-displacement experiment, and molecular docking. • The specific response to HSA was attributed to the albumin-induced restricted intramolecular rotation of flavonoid probe. Discrimination of human serum albumin (HSA) from bovine serum albumin (BSA) based on the fluorescence probe technique is still challenging due to similar chemical structures. In this work, a novel flavonoid-based fluorescent probe AF is reported for successful discrimination of HSA from BSA. The sensing performances of probe, including sensing dynamic, sensitivity and selectivity, have been carefully studied. Moreover, sensing mechanism was elucidated by Job's plot, displacement experiment, and molecular docking, suggesting that the specific response to HSA originated from the albumin-induced restricted intramolecular rotation (RIR) of probe. This work may provide a simple way for designing of novel probes for HSA with high selectivity. [ABSTRACT FROM AUTHOR]

Terminal deoxynucleotidyl transferase (TdT) is a crucial biomarker for diseases such as lymphoblastic leukemia. Herein, a pho tocatalytic co lorimetry and f luorescence dual-signal biosensor (PhoCoF-sensor) for simple, low-cost and sensitive detection of TdT was developed, which integrated with the TdT-triggered polymerization reaction and the fluorescence-photocatalytic dual performance of double-strand DNA/SYBR Green-I (dsDNA/SG-I) complex. The target TdT catalyzed the elongation of single-stranded DNA in the dTTP substrate pool, and then hybridized with complementary DNA to form dsDNA/SG-I complex that exhibited obvious fluorescent and excellent photocatalytic activity. Reactive oxygen species were generated from photosensitization of the dsDNA/SG-I complex acted as the visual colorimetric readout. The PhoCoF-sensor was successfully used to detect TdT activity with a series of color and fluorescence changes in the concentration range from 0.5 U/mL to 20.0 U/mL. The PhoCoF-sensor further improves the assay simplicity and accuracy and reduces the time and cost, which overcomes the limitations of traditional detection TdT methods and single-signal sensors. Additionally, this PhoCoF-sensor can readily be integrated with centrifugal microfluidic device for one-step test and achieve quantitative determination without sophisticated instruments. Moreover, the PhoCoF-sensor has good sensitivity and good practical reliability and is suitable for instant determination in early disease diagnosis and drug discovery. • Photocatalytic colorimetry and fluorescence dual-signal biosensor was developed. • TdT-triggered polymerization reaction without DNA/RNA template. • The dsDNA/SG-I complex has excellent fluorescence-photocatalytic dual performance. • PhoCoF-sensor well integrated with centrifugal microfluidic chip for TdT detection. [ABSTRACT FROM AUTHOR]

Tetracyclines (TCs) are a group of broad-spectrum antibiotics against multiplying microorganisms yet with several adverse effects on humans. Since all types of TCs have the similar chemical skeleton and mechanism of action, quantification of total amount of TCs in the environment was of particular importance. To date, dozens of fluorescent probes have been reported for TCs detection, but only very few of them enabled detection of total TCs. In this study, we report a novel supramolecular sensor constructed by human serum albumin as the recognition moiety and a flavonol fluorophore as the indicator. Under the 370 nm UV excitation, this sensor exhibits the rapid response (5 s), acceptable sensitivity (limit of detection ∼ 0.58 μM), long dynamic detection range (0–20 μM), prominent specificity, and excellent anti-interference properties for analysis of total TCs. The mechanism was carefully validated using 1H NMR, fluorescence titration experiments, molecular docking, and mass spectrometry. We expect this work can inspire more sensor design for TCs quantification. [Display omitted] • A novel fluorescent sensor enables detection of total amount of tetracyclines. • This method can detect tetracycline with rapid response and high selectivity. • The limit of detection for tetracyclines can reach 0.58 μM. • Accurate detection of total tetracycline in real samples is achieved. [ABSTRACT FROM AUTHOR]

Abnormal expression of alkaline phosphatase (ALP) in serum has received considerable attention in health monitoring and disease diagnosis. However, conventional optical analysis based on a single signal must compromise background interference and limited sensitivity in trace analysis. As an alternative candidate, the ratiometric approach depends on the self-calibration of two independent signals in a single test to minimize interferences from the background for accurate identification. Here, a carbon dot/cobalt-metal organic framework nanocoral (CD/Co-MOF NC) mediated fluorescence-scattering ratiometric sensor has been developed for simple, stable, and highly sensitive detection of ALP. ALP-responsive phosphate production was used to coordinate cobalt ion and collapse the CD/Co-MOF NC, resulting in the recovery of fluorescence signal from dissociative CDs and the decrease of second-order scattering (SOS) signal from the cracked CD/Co-MOF NC. The ligand-substituted reaction and the optical ratiometric signal transduction provide a rapid and reliable chemical sensing mechanism. The ratiometric sensor effectively converted ALP into a ratio signal of fluorescence-scattering dual emission throughout a wide linear concentration range of six orders of magnitude with a detection limit of 0.6 mU/L. In addition, self-calibration of fluorescence-scattering ratiometric method can reduce background interference and improve sensitivity in serum, approaching recoveries of ALP from 98.4% to 101.8%. Due to the above advantages, the CD/Co-MOF NC mediated fluorescence-scattering ratiometric sensor readily provides rapid and stable quantitative detection of ALP as a promising in vitro analytical method for clinical diagnostics. [Display omitted] • A CD/Co-MOF NC mediated fluorescence-scattering ratiometric sensor has been developed for highly sensitive detection of ALP. • Dual emission signal readout achieves self-calibration of the method to minimize interferences. • Real sample analysis was completed in a simple and rapid detection process. • The sustainable carbon dots from green source can be easily assembled for CD/Co-MOF NC. [ABSTRACT FROM AUTHOR]

[Display omitted] • A dual-site fluorescent probe for detecting low and high concentration of ClO− was reported. • With the increase of ClO−, the probe showed a fluorescence change from red to green to blue. • The probe can be applied for imaging exogenous and endogenous ClO− in living cells. Hypochlorite (ClO−) is an important bioactive molecule of living system which plays essential roles in many physiological and pathological processes. There is no doubt that the biological roles of ClO− depend highly on the concentration of ClO−. Unfortunately, the relationship between the concentration of ClO− and the biological process is unclear. Toward this purpose, in this work we addressed a core challenge for developing a powerful fluorescence tool for monitoring a wide concentration change (0–14 eq.) of ClO− via two distinct detection manners. The probe displayed fluorescence variation (red to green) upon addition of ClO− (0–4 eq.) and the color of test medium changed from red to colorless witnessed by the naked eyes. Surprisingly, in the presence of higher concentration of ClO− (4–14 eq.), the probe displayed another fluorescent signal change from green to blue. After demonstrating the excellent sensing properties of the probe with ClO− in vitro, it was successfully used to imaging different concentration of ClO− in living cells. We expected that the probe could act as an exciting chemistry tool for imaging of ClO− concentration-dependent oxidative stress event in biological system. [ABSTRACT FROM AUTHOR]

[Display omitted] • A surfactant-assisted fluorescent method is reported for sensitive detection of benfluralin herbicide in water with a LOD of 80 nM. • The role of surfactant on signal amplification has been carefully studied by the polarity-dependent DFT calculation. • The sensing properties including response time, sensitivity, selectivity, and anti-interference ability, have been fully studied. • This surfactant-assisted method enables the fluorescent monitoring of benfluralin in living plants. Developing an effective detection method for benfluralin (BFA) is of great significance, since BFA as most widely used herbicides can be bioaccumulated by aquatic organisms in environment, possessing potential risks to human health. Owing to aggregation-caused quenching effect, most fluorescent detection methods based on donor–acceptor organic fluorophores suffered from very low sensitivity towards BFA in water system, hampering the bioimaging application in plants. In this work, we reported a novel surfactant-assisted fluorescent probe enabling detection of BFA in water with a high sensitivity. The involvement of specific surfactant Triton X100 (TX100) could amplify the response signal of probe more than 100-fold. The detection limit for BFA was determined to be 80 nM, satisfying the environmental protection requirements. Moreover, we demonstrated applications of this strategy for the fluorescent imaging of BFA in plant. The absorbance of BFA into roots of Arabidopsis thaliana and castor seedlings was successfully observed based on this method. [ABSTRACT FROM AUTHOR]

Fipronil, a wildly used pesticide, exhibits high toxicity to pollinators, aquatic organisms, farmland birds, as well as mammals that have GABA receptors, including humans. Thus, developing an effective method for fipronil determination is of great importance. Although the fluorescence assays have the features of easy-to-use, rapid response, high sensitivity and visualized readout, such assay for fipronil was rather difficult to design because fipronil was both chemically and photophysically stable. Herein, we utilized a chalcone dye bound into albumin inner-cavity to construct a novel supramolecular recognition system, for the first time, successfully realizing ratiometric fluorescence detection of fipronil. The sensing mechanism has been carefully verified by the molecular docking, fluorescent titration, DLS tests and fluorescence lifetime. This reported probe could detect fipronil with a rapid response (< 3 min), high sensitivity (LOD ~ 0.01 ppm) and selectivity, good anti-interference property, and significantly, ratiometric color change from green to yellow, which could be discriminated by naked eyes. Moreover, we demonstrated the application of this method in the ratiometric tracking of fipronil in plants (Arabidopsis thaliana). We anticipate this albumin-based supramolecular recognition system would inspire more probe design for environmental monitoring. [Display omitted] • The ratiometric fluorescence detection of fipronil pesticide is reported for the first time. • The recognition system is constructed by a dual-state-emissive chalcone dye that binds into the albumin inner-cavity. • This method could detect fipronil with a fast response, high sensitivity and selectivity. • The specific response to fipronil results from the binding competition between chalcone and fipronil for albumin. • We demonstrate the successful application this method in plant imaging. [ABSTRACT FROM AUTHOR]

• The fluorescence probe based MAPbBr 3 @ZIF-8 showed high selective for ClO−. • The detection limit and quenching constant of ClO− were 31.9 nM and 0.141 µM−1. • The fluorescence probe demonstrated excellent stability in natural water. The extensive use of hypochlorite (ClO−) as oxidant and bleach has drawn serious concern due to their adverse environment and biological impact. Herein, a novel fluorescence probe composite material based on MAPbBr 3 @ZIF-8 was prepared by agitation method in room temperature, using lead bromide, armour ammonia bromine, 2-methylimidazole and zinc acetate as precursors. MAPbBr 3 @ZIF-8 composites exhibited remarkable stability in NaCl aqueous solution and UV lamp. Thus, the MAPbBr 3 @ZIF-8 composites were successfully used as a fluorescence probe for detection of ClO− via electron transfer and dynamic quenching mechanism. The fluorescence probe can detect ClO− in water with high selectivity even existed other anions (HCO 3 −, SO 4 2−, Cl−, SiO 3 2−, CO 3 2−, NO 3 −, HSO 3 −). Meanwhile, the response time of the MAPbBr 3 @ZIF-8 probe could be obtained to less than 40 s. The detection limit and quenching constant were calculated as 31.9 nM and 0.141 µM−1. Furthermore, the fluorescence probe sensor showed excellent stability in natural environment with 94.6%-100.6% recovery rates. The fluorescence probe based MAPbBr 3 @ZIF-8 composites in this study is promising for detecting ClO− anion in water. [ABSTRACT FROM AUTHOR]

[Display omitted] We designed and evaluated a high-performing and biocompatible sensing platform to quantitatively detect glutathione (GSH) in the intracellular environment. To this end, we constructed a fluorescent switch using nitrogen-doped graphene quantum dots (N-GQDs) as fluorescent probes and MoS 2 nanoflowers as the GSH recognition unit. Fluorescence emission of N-GQDs was first switched OFF when combined with MoS 2 nanoflowers due to the fluorescence resonance energy transfer (FRET) mechanism. It was readily switched ON by reducing MoS 2 to Mo3+ in the presence of GSH, enabling the recovery of fluorescent signal. We performed experiments to test the dependence of the sensing platform fluorescence intensity on the concentrations of GSH in the range of 0.4–4.4 mM. The detection limit was 2.47 μM. The monitoring of concentrations of GSH in human retinal pigment epithelium cells (ARPE-19) samples revealed excellent sensing performance with facilitated visualization of the probe, suggesting that the unique sensing strategy has the exceptional anti-interference property for assessing the intracellular GSH quantity in diagnostics and biomedical research. The OFF/ON switch for the detection of GSH was explored to create a XNOR molecular logic gate. [ABSTRACT FROM AUTHOR]

• The strategy of donor engineering to enhance fluorescence brightness is reported. • The methylpiperazine-substituted flavonoid shows high fluorescence brightness in water. • A novel fluorescent probe can sense cysteine both in water and in living cells. Increasing demand for detecting environmental and biological analytes in aqueous solutions based on fluorescent probes has raised the bar for the fluorophores used. Especially, the twisted intramolecular charge transfer (TICT) state of fluorophore can trigger the formation of a charge-separated non-emissive specie, leading to a low fluorescence brightness. In this work, we performed a simple donor engineering on the flavonoid-based fluorophores to regulate the TICT formation. A systematic study on relationship between donor structure and photophysical properties has been carried out. Among a series of flavonoids, the methylpiperazine-substituted one exhibited the strongest fluorescence brightness in water since the methylpiperazine could rigidify the rotation of donor moiety to suppress TICT state. Moreover, a novel fluorescent probe based on this flavonoid successfully realized the cysteine detection both in water and in living cells. This work confirmed the validity of design strategy by inhibiting TICT to enhance the fluorescence brightness, and also provided a practical flavonoid-based fluorophore for further bioimaging applications. [ABSTRACT FROM AUTHOR]