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1.
Mikrochim Acta ; 188(10): 324, 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34490510

RESUMO

N, Cl-doped carbon dots (N, Cl-CDs) were prepared by hydrothermal method from rhodamine B (RhB) and ethylenediamine (EDA). The resulting N, Cl-CDs exhibited fascinating solvent dependence and strict excitation independence. As the polarity of the solvent increased (from tetrahydrofuran (THF) to water), the emission spectrum of N, Cl-CDs was redshifted and the fluorescence efficiency decreased, which were attributed to hydrogen bond-induced aggregation. Taking advantage of these attributes, the N, Cl-CDs were used as suitable probes for fluorescence and colorimetric dual-mode detection of water in THF. The linear relationship was 0.5-100% water with the detection limit down to 0.093%. Moreover, the sensing platform was converted into a paper-based sensor for handy, real-time, and visible humidity sensing. N, Cl-CDs/PVA films were fabricated and realized continuously tunable solid-state fluorescence, further expanding their practical application.

2.
Anal Methods ; 13(37): 4246-4255, 2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34591950

RESUMO

Dual-excitation and dual-emission carbon dots (CDs) have been prepared by simple one-step hydrothermal treatment of p-phenylenediamine and 5-aminosalicylic acid. The as-prepared CDs emit bright green fluorescence under excitation at 320-400 nm and bright orange fluorescence under excitation at 490-560 nm. Interestingly, the CDs can be employed as a dual-excitation and dual-emission fluorescent probe for Fe3+ detection in aqueous solution and living cells. Furthermore, the obtained CDs can function as a promising dual-excitation and dual-emission temperature sensor. Additionally, the CDs can be utilized for lysosomal targeting.

3.
Analyst ; 146(17): 5357-5361, 2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-34333580

RESUMO

Nitrogen doped carbon dots (N-CDs) were synthesized by a one-step hydrothermal method with dopamine and ethylenediamine. The as-prepared N-CDs were characterized via transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), fluorescence spectrophotometer, UV-Vis spectrophotometry and Fourier transform infrared spectroscopy (FTIR). The average particle dimension of the as-prepared N-CDs was 2.68 nm, and the best excitation and emission wavelengths were 405 nm and 535 nm, separately. N-CDs exhibits excellent selectivity and sensitivity to detect the curcumin (Cur), attaining a wider linear range of 97.5 nM-67.9 µM and a limit of detection (LOD) of as low as 94 nM. Interestingly, N-CDs can also give responsive signals of a visible colour change (yellow to red). Moreover, a novel fluorescent/colorimetric dual-mode method has been successfully employed for the determination of Cur in real samples with good recoveries (94%-110%) and precision (RSD = 0.3-2.9%).


Assuntos
Curcumina , Pontos Quânticos , Carbono , Colorimetria , Corantes Fluorescentes , Nitrogênio , Espectrometria de Fluorescência
4.
Anal Methods ; 13(32): 3561-3568, 2021 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-34313265

RESUMO

N-doped blue-fluorescence carbon dots (N-CDs) were fabricated via a one-pot hydrothermal method using folic acid and p-phenylenediamine. The obtained N-CDs exhibited strong fluorescence (FL) with a considerable quantum yield (QY) of 21.8% and exceptional optical stability under different conditions. Upon introducing Cr(vi), blue FL of N-CDs was distinctly quenched. On subsequent addition of l-AA, the FL of N-CDs could be partially recovered. The fluorescence changes of N-CDs have been utilized to detect Cr(vi) and l-AA in aqueous solutions with linear ranges of 0.10-150 µM and 0.75-2.25 mM, respectively, as well as limit of detection values of 9.4 nM and 25 µM, respectively. Furthermore, as-obtained N-CDs can be extended to monitor the fluctuation of intracellular Cr(vi) and l-AA. More intriguingly, N-CDs can target lysosomes with a satisfactory Pearson correction coefficient of 0.87, which indicates a promising application prospect in the biomedical field.


Assuntos
Carbono , Pontos Quânticos , Cromo , Lisossomos , Nitrogênio , Espectrometria de Fluorescência
5.
Talanta ; 233: 122593, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34215082

RESUMO

The latent fingerprints (LFPs) at the crime scene are unique and stable, which are considered as an important clue in criminal justice and forensic identification. Herein, a butterfly-shaped molecule DPTS with solid fluorescence plus excited-state intramolecular proton transfer (ESIPT) properties was used to develop for enhancing the visualization of the LFPs. Considering the solid fluorescence of DPTS, the color and efficiency of DPTS with a large Stokes shift (216 nm) can be tuned by changing the morphology of its aggregates, and gradually red-shifted (green-yellow-red) with increasing water content. Furthermore, its effectiveness for the detection of LFPs was demonstrated on various different substrates including paper box, tinfoil and weighting paper. The emissive fingerprint of DPTS obtained gave good fluorescence images with high contrast and resolution such as the core, delta, bifurcation, ridge termination, independent ridge and pores. Caging of the phenol donor of DPTS with a sensitive biomarker group provided DPTS-ONOO-, which had high sensitive with detection limit of 5 nM and the quantification limit of 21 nM toward ONOO-. Modularly derived DPTS-ONOO- was synthesized and demonstrated specific fluorescence imaging of exogenous and endogenous peroxynitrite (ONOO-) in living macrophage cells.


Assuntos
Corantes Fluorescentes , Prótons , Ácido Peroxinitroso , Fenol , Fenóis
6.
Analyst ; 146(13): 4348-4356, 2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34113936

RESUMO

A new fluorescent probe, 3-(benzo[d]thiazol-2-yl)-5-bromosalicylaldehyde-4N-phenyl thiosemicarbazone (BTT), for ratiometric sensing of Zn2+ ions in methanol/HEPES buffer solution (3 : 2, pH = 7.4) is reported in this paper. The presence of Zn2+ ions yields a significant blue shift in the maximum emission of BTT from 570 nm to 488 nm, accompanied by a clear color change from orange to green. This emission change of BTT upon binding to Zn2+ in a 1 : 1 ratio may be due to the block of excited state intramolecular proton transfer (ESIPT) as well as chelation enhanced fluorescence (CHEF) on complex formation. The limit of detection (LOD) determined for Zn2+ quantitation was down to 37.7 nM. In addition, the probe BTT displays the ability to image both exogenous Zn2+ ions loaded into HeLa cells and endogenous Zn2+ distribution in living SH-SY5Y neuroblastoma cells.


Assuntos
Benzotiazóis , Corantes Fluorescentes , Células HeLa , Humanos , Espectrometria de Fluorescência , Zinco
7.
Spectrochim Acta A Mol Biomol Spectrosc ; 261: 120044, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34118522

RESUMO

Fluorescent probes have contributed greatly to our understanding of the biological role of peroxynitrite (ONOO-). The ONOO- fluorescence probe characterized by the arlyboronate received a moderate opening fluorescence response, and the borate-masked probe significantly increased the sensitivity of ONOO-. Thus, two simple fluorescent probes (ADB and ANB) with the recognition receptor of phenyl boronate moiety were constructed for the detection of ONOO-. The change of emission spectrum was affected differently by the electron donating (or withdrawing) of the substituents. ANB was shown to have a low sensitivity and quantum yield towards ONOO- in aqueous solution, whereas ADB with aggregation-induced emission (AIE) process exhibited not only good sensitivity for ONOO- with a detection limit of 75 nM, but also ADB could be used to quantitative detecting ONOO- in response to concentrations of ONOO- within 20 s. Importantly, ADB had good performance for the detection of exogenous ONOO- in the RAW 264.7 cells.


Assuntos
Corantes Fluorescentes , Ácido Peroxinitroso , Animais , Boratos , Camundongos , Imagem Óptica , Células RAW 264.7
8.
Spectrochim Acta A Mol Biomol Spectrosc ; 261: 120028, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34119768

RESUMO

A novel visual nanoprobe was developed for the sequential detection of morin and zinc ion (Zn2+) based on Cl and N co-doped carbon quantum dots (ClNCQDs) via a fluorometric and colorimetric dual-readout mode. The yellow fluorescence ClNCQDs was synthesized by the one-step hydrothermal treatment of o-chlorobenzoic acid and p-phenylenediamine. The most distinctive property of the ClNCQDs is the large stokes shift (177 nm), which is significantly higher than other reported CQDs. The fluorescence of the ClNCQDs can be effectively quenched by morin based on the synergistic effect of IFE, electrostatic interaction, and dynamic quenching process, and recovered upon the addition of Zn2+ due to strong interaction between morin and Zn2+. The nanoprobe exhibited favorable selectivity and sensitivity toward morin and Zn2+ with detection limits of 0.09 µM and 0.17 µM, respectively. Simultaneously, the color of the ClNCQDs solution was changed (light-pink â†’ faint-yellow â†’ dark-yellow) along with the variation of the fluorescence signal of the ClNCQDs. This proposed nanoprobe was successfully applied for morin and Zn2+ analyses in actual samples and live cells with high accuracy. The results of this study demonstrate the great application prospects of the ClNCQDs for morin and Zn2+ detection in complex actual samples and biosystems.


Assuntos
Pontos Quânticos , Carbono , Colorimetria , Flavonoides , Limite de Detecção , Zinco
9.
Food Funct ; 12(14): 6334-6347, 2021 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-34100053

RESUMO

Herein, PPy@MnO2 nanocomposites were first harvested by anchoring MnO2 nanosheets on polypyrrole (PPy) nanoparticles via an in situ redox reaction, then polyethylene glycol (PEG) modifier and methylene blue (MB) photosensitizer were linked through electrostatic interactions to obtain PPy@MnO2-PEG-MB nanoarchitectures. PPy nanoparticles ensure photothermal therapy (PTT) ability and MnO2 nanosheets ameliorate tumor hypoxia for enhanced photodynamic therapy (PDT). Therefore, a multifunctional nanotherapeutic system was constructed for the combined PTT/PDT of tumors. For extracellular photothermal properties, the optimal temperature elevation was 52.6 °C with 54.4% photothermal conversion efficiency. The extracellular PDT ability was measured by detecting 1O2 generation; more 1O2 was produced under acidic conditions in the presence of H2O2 (a simulated tumor microenvironment). The effective cellular uptake of the nanotherapeutic system in HeLa cells was observed by confocal laser scanning microscopy (CLSM). CLSM also indicated that more 1O2 was generated by the nanotherapeutic system as compared to free MB in HeLa cells, confirming the amelioration of tumor hypoxia by MnO2 nanosheets. MTT assays demonstrated that the nanotherapeutic system possessed superior biocompatibility without laser irradiation, and the lowest cell viabilities for single PTT and PDT groups were 13.78%, 38.82% respectively, while there was only 1.29% cell viability in the combined PTT and PDT group. These results suggest that the strategy of assembling PPy with MnO2 for a multifunctional PTT and enhanced PDT nanoplatform was realized, and opens up an unimpeded approach for integrating photothermal reduction materials with MnO2 for use in synergistic PTT and PDT.

10.
Anal Chem ; 93(22): 8019-8026, 2021 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-34037378

RESUMO

Elucidating the intrinsic relationship between diseases and lipid droplet (LD) polarity remains a great challenge owing to the lack of the research on multiple disease models. Until now, the visualization of abnormal LD polarity in models of inflammation and clinical cancer patient samples has not been achieved. To meet the urgent challenge, we facilely synthesized a robust LD-specific and polarity-sensitive fluorescent probe (LD-TTP), which consists of a triphenylamine segment as an electron-donor group (D) and a pyridinium as an electron-acceptor moiety (A), forming a typical D-π-A molecular configuration. Owing to the unique intramolecular charge transfer effect, LD-TTP exhibits high sensitivity to polarity change in the linear range from Δf = 0.258 to 0.312, with over 278-fold fluorescence enhancement. Moreover, we revealed that LD-TTP possessed satisfactory ability for sensitively monitoring LD-polarity changes in living cells. Using LD-TTP, we first demonstrated the detection of LD-polarity changes in fatty liver tissues and inflammatory living mice via confocal laser scanning fluorescence imaging. Surprisingly, the visualization of LD polarity has been achieved not only at the cellular levels and living organs but also in surgical specimens from cancer patients, thus holding great potential in the clinical diagnosis of human cancer. All these features render LD-TTP an effective tool for medical diagnosis of LD polarity-related diseases.


Assuntos
Fígado Gorduroso , Neoplasias , Animais , Corantes Fluorescentes , Humanos , Inflamação/diagnóstico por imagem , Gotículas Lipídicas , Camundongos , Neoplasias/diagnóstico por imagem
11.
Mikrochim Acta ; 188(6): 183, 2021 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-33970343

RESUMO

Carbon dots (CDs) are a rising star in the field of cellular imaging, especially cytoplasmic imaging, attributing to the super-stable optical performance and ultra-low biological toxicity. Nucleolus can accurately reflect the expression state of a cell and is strongly linked to the occurrence and development of many diseases, so exploring bran-new CDs for nucleolus-orientation imaging with no-wash technology has important theoretical value and practical significance. Herein, nitrogen-doped carbon dots (N-CDs) with green fluorescence (the relative fluorescence quantum yield of 24.4%) was fabricated by the hydrothermal treatment of m-phenylenediamine and p-aminobenzoic acid. The N-CDs possess small size, bright green fluorescence, abundant surface functional groups, excellent fluorescence stability and good biocompatibility, facilitating that the N-CDs are an excellent imaging reagent for cellular imaging. N-CDs can particularly bind to RNA in nucleoli to enhance their fluorescence, which ensures that the N-CDs can be used in nucleolus-orientation imaging with high specificity and wash-free technique. This study demonstrates that the N-CDs have a significant feasibility to be used for nucleolus-orientation imaging in biomedical analysis and clinical diagnostic applications.

12.
Talanta ; 231: 122350, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-33965020

RESUMO

Recently, room temperature phosphorescence (RTP) feature of carbon dots (CDs) has gradually diverted researchers' attention from fluorescence and sparks new research boom due to its ultra-long luminescence lifetime and large Stokes shift. Some attempts have been made to construct CDs-based RTP materials, and had seen some important progress. However, few review articles were published to systematically summarize them. Herein, we summarize the recent synthesis advances of the RTP CDs, mainly focusing on matrix-assisted method and self-protection method. Different construction methodologies lead to different RTP properties and luminescence mechanisms. Based on this fact, we discuss the correlation between them and further summarize their potential applications in sensing, light-emitting diodes, anti-counterfeiting, and information protection filed. Finally, the currently existing problems and development perspectives of CDs-based RTP materials was proposed.

13.
Spectrochim Acta A Mol Biomol Spectrosc ; 256: 119751, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-33819765

RESUMO

The B,N dual-doped carbon dots (B,N-CDs) for ratiometric fluorescence detection the morin were prepared from sodium tetraborate and polyethyleneimine through the single-step hydrothermal method. The B,N-CDs exhibited the optimum excitation and emission wavelength at 340 nm and 467 nm, respectively. Interestingly, the intensities of emission peak at 467 nm of B,N-CDs reduced meanwhile a new peak emerged at 560 nm with the continuous addition of morin, which revealed the ratio fluorescence characteristic between F560nm/F467nm and morin concentration with the linearity range and detection limit of 14.5-32.5 µmol/L and 0.3 µmol/L (S/N = 3), respectively. The interference of common antibiotics and remedies could be ignored when the concentration of morin was detected by the B,N-CDs, which demonstrating the outstanding selectivity. Furthermore, the proposed fluorescence method is used to detect morin in urine with recoveries are 99.8-104.5%. The results of this research indicate the feasibility and practicality of B,N-CDs as an effective fluorescent probe for the determination of morin.


Assuntos
Carbono , Pontos Quânticos , Flavonoides , Fluorescência
14.
Analyst ; 146(7): 2138-2143, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33651055

RESUMO

To selectively detect H2S based on the thiolysis reaction of 7-nitro-1,2,3-benzoxadiazole (NBD), amines attracted increasing attention since NBD amine is regarded as a new H2S reaction site. Herein, a novel fluorescent probe, triphenylamine piperazine NBD (TPA-Pz-NBD), was developed. The results showed that it exhibited high selectivity towards H2S via fluorescence spectroscopy and solution color. Furthermore, TPA-Pz-NBD not only detected H2S by a dual-channel, turn-on fluorescence signal at 500 nm and turn-off fluorescence signal at 545 nm, respectively, but also displayed a wide detection range of 0-125 µM. In addition, living cell imaging results indicated that TPA-Pz-NBD holds potential for the detection of intracellular H2S.

15.
Anal Chem ; 93(6): 3241-3249, 2021 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-33539094

RESUMO

Mitophagy plays a crucial role in maintaining intracellular homeostasis through the removal of dysfunctional mitochondria and recycling their constituents in a lysosome-degradative pathway, which leads to microenvironmental changes within mitochondria, such as the pH, viscosity, and polarity. However, most of the mitochondrial fluorescence viscosity probes only rely on electrostatic attraction and readily leak out from the mitochondria during mitophagy with a decreased membrane potential, thus easily leading to an inaccurate detection of viscosity changes. In this work, we report a mitochondria-immobilized NIR-emissive aggregation-induced emission (AIE) probe CS-Py-BC, which allows for an off-on fluorescence response to viscosity, thus enabling the real-time monitoring viscosity variation during mitophagy. This system consists of a cyanostilbene skeleton as the AIE active core and viscosity-sensitive unit, a pyridinium cation for the mitochondria-targeting group, and a benzyl chloride subunit that induces mitochondrial immobilization. As the viscosity increased from 0.903 cP (0% glycerol) to 965 cP (99% glycerol), CS-Py-BC exhibited an about 92-fold increase in fluorescence intensity at 650 nm, which might be attributed to the restriction of rotation and inhibition of twisted intramolecular charge transfer in a high viscosity system. We also revealed that CS-Py-BC could be well immobilized onto mitochondria, regardless of the mitochondrial membrane potential fluctuation. Most importantly, using CS-Py-BC, we have successfully visualized the increased mitochondrial viscosity during starvation or rapamycin-induced mitophagy in real time. All these features render CS-Py-BC a promising candidate to investigate mitophagy-associated dynamic physiological and pathological processes.


Assuntos
Corantes Fluorescentes , Mitofagia , Células HeLa , Humanos , Mitocôndrias , Viscosidade
16.
J Agric Food Chem ; 69(9): 2836-2844, 2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33621092

RESUMO

In this work, we synthesized carbon nanodots (CNDs) by a one-pot hydrothermal method to carbonize precursors of dry carnation petals and polyethylenimine. The obtained CNDs possess favorable photostability, good biocompatibility, and excellent water solubility, which can serve as a dual-responsive nanosensor for the determination of vitamin B2 (VB2) and pH. A unique ratiometric fluorescence resonance energy transfer probe was developed through a strong interaction between VB2 and surface moieties of CNDs. CNDs emitted at 470 nm; however, in the presence of VB2, an enhanced emission peak was clearly observed at 532 nm. The value of I532/I470 exhibits a stable response to the VB2 concentration from 0.35 to 35.9 µM with a detection limit of 37.2 nM, which has been used for VB2 detection in food and medicine samples and ratiometric imaging of VB2 in living cells with satisfying performance. In addition, the proposed CNDs also displayed pH-sensitive behavior and can be a turn-off fluorescent sensor to monitor pH. The fluorescent intensity at 470 nm is a good linear response against pH values from 3.6 to 8, affording the capability as a single-emissive nanoprobe for intracellular pH sensing.


Assuntos
Carbono , Pontos Quânticos , Corantes Fluorescentes , Concentração de Íons de Hidrogênio , Riboflavina , Vitaminas
17.
Biomater Sci ; 9(6): 2255-2261, 2021 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-33533378

RESUMO

Intracellular pH and hypochlorite (ClO-) concentration play an important role in life activities, so there is an urgent need to develop a valid strategy to monitor pH and ClO- in biological systems with high sensitivity and specificity. In this study, we report long-wavelength emission nitrogen-doped carbon dots (N-CDs) and their potential applications in intracellular pH variation, ClO- sensing and cell imaging. The N-CDs were prepared via a facile one-pot hydrothermal method of neutral red (NR) and glutamine (Gln). N-CDs exhibited a pH-sensitive response in the range of 4.0-9.0 and a good linear relationship in the range of 5.6-7.4, which indicated that N-CDs are an ideal agent for monitoring pH fluctuations in living cells. In addition, ClO- was capable of reducing the photoluminescence of N-CDs based on static quenching. The linear range is 1.5-112.5 µM and 112.5-187.5 µM, and the LOD is 0.27 µM. Besides, the as-fabricated N-CDs have been smoothly achieved to monitor pH and ClO- in PC-12 living cells due to their great biocompatibility and lower cytotoxicity, demonstrating their promising applications in the biomedical field. Compared with other CD-based methods, the as-proposed N-CDs have a longer fluorescence emission, which makes them potentially valuable in biological systems. The results pave a way towards the construction of long-wavelength carbon-based nanomaterials for fluorescence sensing and cell imaging.


Assuntos
Carbono , Pontos Quânticos , Corantes Fluorescentes , Concentração de Íons de Hidrogênio , Ácido Hipocloroso , Nitrogênio
18.
Spectrochim Acta A Mol Biomol Spectrosc ; 252: 119506, 2021 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-33561684

RESUMO

Azithromycin (AZM)1 is one of the most widely used antibiotics. AZM abuse is easy to cause great harm to human body, so developing a rapid and sensitive method to detect AZM is of great importance. Herein, 3-aminothiophenol as only reaction precursor, nitrogen and sulfur co-doped carbon quantum dots (N,S-CQDs)2 were fabricated by one-step hydrothermal carbonization method. All characteristics demonstrate that N,S-CQDs possess good water solubility, high fluorescence stability and low cytotoxicity. Without being disturbed by amino acids and drugs, the most interesting finding is that AZM can efficiently quench the fluorescence of N,S-CQDs by a synergistic effect of electrostatic interaction and static quenching. A fluorescent probe for the detection of AZM was constructed with high selectivity and good sensitivity, achieving two linear ranges of 2.5-32.3 µM and 37.2-110 µM and a limit of detection of 0.76 µM. The proposed fluorescent method was used for the detection of AZM in cells with fulfilling results. More importantly, the fluorescent probe was successfully used to the detection of AZM in tablets and human urine with recovery rate and relative standard deviations of 98.2-104.8% and 0.04-3.46%, respectively, which was confirmed by the standard method of HPLC-UV. This finding illustrates the usefulness and feasibility of N,S-CQDs as an effective fluorescent probe for the detection of AZM in tablets and human urine, which is helpful for supervising and guiding pharmacy.


Assuntos
Pontos Quânticos , Azitromicina , Carbono , Humanos , Nitrogênio , Comprimidos
19.
Mikrochim Acta ; 188(1): 16, 2021 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-33399925

RESUMO

Nitrogen, sulfur, phosphorus, and chlorine co-doped carbon nanodots (NSPCl-CNDs) were fabricated by acid-base neutralization and exothermic carbonization of glucose. The obtained NSPCl-CNDs possess excellent fluorescence properties and good biocompatibility. Curcumin (Cur) can dramatically quench the fluorescence of NSPCl-CNDs based on a synergistic effect of electrostatic interaction, inner filter effect, and static quenching, so a "turn-off" fluorescent probe for Cur detection was constructed with linear ranges of 0.24-13.16 µM and 13.62-57.79 µM. The LOD and LOQ of this fluorescent probe for Cur are 8.71 nM and 29.03 nM, respectively. More importantly, the fluorescence of the NSPCl-CNDs-Cur system can be recovered by europium ion (Eu3+), so a "turn-on" fluorescent probe for Eu3+ determination was established. The linear range, LOD, and LOQ for the detection of Eu3+ were 2.36-32.91 µΜ, 73.29 nM, and 244.30 nM, respectively. The proposed fluorescence methods were successfully utilized for Cur and Eu3+ determination in real samples with recoveries in the range 95.64-104.13% and 97.06-98.70%, respectively. Furthermore, the qualitative analysis of Cur can be realized by reagent strips with satisfying results. Finally, the as-constructed "off-on" fluorescent probe was successfully used to sequentially analyze Cur and Eu3+ at the cellular level. This method is simple and easy to implement, manifesting that NSPCl-CNDs have potential application value in fluorescent probing, food and drug testing, environmental monitoring, and cellular labeling. Graphical abstract.

20.
J Hazard Mater ; 409: 124894, 2021 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-33412470

RESUMO

In this work, a visible-light-driven photoelectrochemical (PEC) sensing platform was developed based on BiOI nanoflowers/TiO2 nanotubes (BiOI NFs/TiO2 NTs) for detection of atrazine (ATZ). The BiOI NFs/TiO2 NTs p-n heterojunctions synthesized by decorating BiOI NFs on TiO2 NTs via simple hydrothermal approach exhibit strong visible-light absorption ability, high photocurrent response and PEC activity. Thus BiOI NFs/TiO2 NTs heterostructures were first explored to act as the photoelectrode for the immobilization of the anti-ATZ aptamer to develop a PEC sensing platform. The design PEC aptasensing platform exhibits prominent analytical performance for determination of ATZ with a low detection limit of 0.5 pM under visible-light irradiation, and displays good selectivity for ATZ in the control experiments. The superior behavior of the sensing platform could be ascribed to the design of the appropriate sensing material with tubular microstructure, excellent PEC response of the photoelectrode, and the large loading amount of aptamer. Meanwhile, the PEC sensing platform was used to determine ATZ in environmental samples and a satisfied result was obtained.

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