Fluorescent Probe For Selective Detection Research Articles

An anthracenecarboximide-guanidine fluorescent probe for selective detection of glyoxals under weak acidic conditions.

An anthracenecarboximide-guanidine based turn-on fluorescent probe ANC-DCP-1 for selective detection of glyoxals (methylglyoxal and glyoxal, GOS) over formaldehyde under weak acidic conditions around pH 6.0 was reported. The probe showed great potential in studying relative GOS levels in weak acidic biological fluids such as in urine for diabetic diagnosis and prognosis, and also found application in the food industry such as for fast unique manuka factor (UMF) scale determination of Manuka honey.

A dual responsive fluorescent probe for selective detection of cysteine and bisulfite and its application in bioimaging.

A coumarin-based dual responsive fluorescent probe with a simple structure was developed for the detection of Cys and HSO3−. Under simulated physiological conditions, Cou-F displayed an on–off fluorescence response to Cys at 521 nm and an off–on fluorescence response to HSO3− at 500 nm. Furthermore, Cou-F had the advantages of high sensitivity, strong specificity and rapid response. The detection limits of Cou-F toward Cys and HSO3− were 0.54 μM and 0.65 μM, respectively. Cou-F enabled high selective responses to Cys and HSO3− over other biologically related species. The response times of Cou-F toward Cys and HSO3− were 80 s and 100 s. The fluorescence imaging of Cys and HSO3− was achieved in living RAW246.7 cells.

An Acetyl-Hydrolyzing Nir Fluorescent Probe for Selective Detection of Hydrogen Peroxide in Cells

An Acetyl-Hydrolyzing Nir Fluorescent Probe for Selective Detection of Hydrogen Peroxide in Cells

New pyrazoline based fluorescent probes for selective detection of Al3+ ion in aqueous solution

Two new pyrazoline derivatives DBS and DSS were designed and synthesized for fluorescent detection of Al3+ ion. The photophysical properties were studied in almost 100% aqueous solution (containing 1% DMSO, v/v). Both DBS and DSS had high selectivity and sensitivity toward Al3+ ion over other interfering analytes, and DBS showed higher fluorescence intensity to Al3+ ion than DSS. The limit of detection value was calculated as 7.50 × 10−9 M, 1.76 × 10−8 M for DBS and DSS, respectively, which are far below the WHO limit (7.41 μM) for Al3+ in drinking water. The binding mode of DBS and DSS toward Al3+ is 1:1 through CO and CN groups confirmed by 1H NMR, IR and DFT analysis. Both DBS and DSS detected Al3+ by the chelation-enhanced fluorescence (CHEF) mechanism. Furthermore, the probes were successfully applied to detect Al3+ not only in living cells but also in real water and pharmaceutical samples.

Designing an intriguingly fluorescent N, B-doped carbon dots based fluorescent probe for selective detection of NO2− ions

Low-cost nitrogen and boron-doped carbon nanodots (CPAP-CDs) with a high quantum yield (64.07%) were synthesized through a facile hydrothermal treatment. The obtained CPAP-CDs exhibited wide absorption, strong fluorescence, and pH-dependent behavior. The high fluorescence of CPAP-CDs was quenching in the presence of the nitrite ion in a concentration-dependent manner. The detection limit was as low as 6.6 nM with a wide linear detection range of 2 μM − 1 mM. Diazotization between the NO2− ion and CPAP-CDs resulted in the aggregation of CPAP-CDs and aggregation-induced emission quenching. The as-designed method was tested further with different water samples, such as tap, drinking, and seawater.

A hemicyanine-based fluorescence probe for selective detection of CYP2D6 in living cells and tumor-bearing mice

Cytochrome P450 (CYP) 2D6, as the only active CYP2D subfamily enzyme in humans, involved in metabolizing 25% of clinical drugs, including antidepressants, antiarrhythmic drugs, antipsychotics and analgesics. Herein, two novel enzyme-activatable fluorescent probes (McMe and BnMcMe) were constructed and synthesized to monitor the activity of CytochromeP4502D6 (CYP2D6) in complex biological systems. McMe possessed excellent selectivity and sensitivity in response to CYP2D6 enzyme with 9-fold fluorescence changes and the limit of detection (LOD) = 0.052 nM. The fruitful application of McMe in living cells and tumor-bearing mice implied that it can be used to measure the activity of endogenous CYP2D6. These researches indicated that McMe could be served as an effective molecular tool to specifically bio-image the activity of endogenous CYP2D6 in nude mice, which may provide assistance to investigate the function of CYP2D6 in drug metabolism and pathologic process.

Novel benzotriazole-based probes for the selective detection of Cu(II)

In this paper, a new kind of fluorescent probe - benzotriazole derivative system was constructed by amino derivatization reaction. By studying the spectral properties of the probe, we found that both the mono-substituted and di-substituted products of the reaction can be used as fluorescent probes for selective detection of Cu2+ ion. Therefore, we can selectively obtain different kinds of fluorescent probes by adjusting the reaction conditions. And these probes have the advantages of low detection limit (3a: 8.83 µM; 3b: 8.62 µM; 3c: 2.01 µM) and high selectivity for other ions (Ca2+,Co2+,Zn2+,Fe3+,Cs+,K+,Mg2+,Ni2+,NH4+,Al3+,Na+,Cr3+,Cd2+). In addition, the fluorescence intensity of these probes responds linearly to [Cu2+], and the presence of Cu2+ ion can be sensitively detected by obvious fluorescence quenching.

A multi-responsive coumarin\u2013benzothiazole fluorescent probe for selective detection of biological thiols and hydrazine

Biothiols play important roles in various physiological and biological processes, which closely related to many diseases. Hydrazine is widely used in the chemical industry, but it is harmful to humans and animals. Therefore, it is very important to develop a fluorescent probe that can simultaneously detect biological thiols and hydrazine. In this work, a new fluorescent probe (2E,4Z)-2-(benzo[d]thiazol-2-yl)-5-chloro-5-(7-(diethylamino)-2-oxo-2H-chromen-3-yl)penta-2,4-dienenitrile (BCD) was synthesized by integrating coumarin and benzothiazole acetonitrile. Featured with four binding sites and different bonding mechanism between probe with biothiols and hydrazine, this probe exhibited fluorescent turn-on for distinguishing Cys, Hcy, GSH and hydrazine with 760-, 8-, 6- and 637-fold fluorescent intensity increase at 502, 479, 476 and 458 nm, respectively, through different excitation wavelengths. Research on the effect of pH on the fluorescent performance of BCD shows that the probe exhibits superior stability in a weakly alkaline to weakly acidic environment, which will facilitate the detection of biological thiols or hydrazine hydrate by BCD. Selectivity studies have shown that the probe has high specificity to biological thiols and hydrazine, which is of great significance to the application of BCD.

BODIPY-based fluorescent probe for selective detection of HSA in urine

Quantitative recognition of human serum albumin (HSA) is of great importance in the fields of biology and biomedicine. In biological fluids, HSA has been used as an important biomarker for disease early diagnosis. For example, microalbuminuria has been regarded as an early indicator of diabetic nephropathy. Therefore, it is of great significance to monitor HSA in urine. In this work, a BODIPY-based fluorescence probe, BDY-OH, was constructed for HSA detection, which showed a high signal to noise ratio and high selectivity. In addition, plot of fluorescence intensity exhibited a 90-fold enhancement and a good linear correlation from 0 mg/mL to 0.4 mg/mL. Encouraged by the outstanding properties, the ability of BDY-OH to distinguish proteinuria from normal urine was tested among 39 clinical urine samples and the excellent recognition rate of 89.7% suggested a great significance for the early diagnosis of kidney related diseases. We look forward to using the BDY-OH method as a new tool for preclinical diagnosis of HSA in urine in the future.

Facile preparation of highly thermosensitive N-doped carbon dots and their detection of temperature and 6-mercaotopurine

Carbon dots (CDs) have sparked immense interest because of their attractive optical properties in recent years, but the synthesis of multifunction CDs is still worth investigating. In this paper, a thermosensitive N-doped carbon dots (N-CDs) were prepared by facile hydrothermal method with sodium citrate and NH4Cl as raw materials. The N-CDs with a fluorescence quantum yield of 27.4% are excitation-independent, small size (1.34 nm), and good water-soluble. Importantly, the N-CDs display marvelous thermosensitive fluorescence response with good linear relationship, reversibility, and restorability in a range from 15 to 75 ℃, which can be applied to temperature sensing. Detailed characterization show that the thermosensitive fluorescence mechanism was the activation of nonradiative channels in higher temperatures. Besides, based on the inner filter effect (IFE), N-CDs could be served as a fluorescent probe for selective detection of 6-mercaptopurine (6-MP) without any modification or functionalization. The simple and efficient strategy for 6-MP sensing was quantified in a linear range of 1–90 µM with a detection limit of 0.86 µM and also can be applied to lake water and serum samples with satisfying recoveries.

Irreversible coumarin based fluorescent probe for selective detection of Cu2+ in living cells

Copper ion (Cu2+) is an essential part of the living organisms. Cu2+ ions play a vital role in many biotic processes. An abnormal amount of Cu2+ ions may result in serious diseases. Herein, a novel “fluorescent ON” probe NC-Cu to trace minute levels of Cu2+ ions in presence of various biological active species has been developed. Lysosomal cells targeting group (Morpholine) was added to the probe. The spectral properties of probe NC-Cu were recorded in HEPES buffer (0.01 M, pH = 7.4, comprising 50% CH3CN, λex = 430 nm, slit: 5 nm). The synthesized probe NC-Cu work based on copper promoted catalytic hydrolysis of hydrazone and shows remarkable fluorescence enhancement. The reaction of the probe with Cu2+ ions was completed within 20 min. An excellent linear relationship (R2 = 0.9952) was found and the limit of detection (LOD, according to the 3σ/slope) for Cu2+ ions was calculated to be 5.8 µM. Furthermore, NC-Cu was effectively functional in the living cells (KYSE30 cells) to trace Cu2+ ions.

A fluorescent probe for selective detection of Fe3+ by using a self-assembled nitrogen-doped carbon quantum dots-3,4,9,10-perylenetetracarboxylic acid composite

A fluorescent probe for selective detection of Fe3+ by using a self-assembled nitrogen-doped carbon quantum dots-3,4,9,10-perylenetetracarboxylic acid composite

A metal-free fluorescent probe for selective detection of histidine

A highly selective fluorescent probe has been discovered for the recognition of L-histidine (His) without the need to use a metal cation. Mechanistic studies including 1D and 2D 1H and 13C NMR analyses and DFT calculation have revealed that the 2-formyl group of the 1,1′-binaphthyl-based probe reacts with His to form a multicyclic product and the structural rigidity of this product should have contributed to the greatly enhanced fluorescence. The reactions of all the other amino acids with the probe cannot generate such a structurally rigid product and thus exhibit no or much smaller fluorescence enhancement. This probe can also be easily modified to allow the selective detection of His to be conducted in aqueous or fluorous solution.

Aqueous synthesis of L- methionine capped PbS quantum dots for sensitive detection and quantification of arsenic (III)

A simple aqueous chemical approach was employed for the synthesis of the PbS quantum dots (QDs) using L-methionine (Meth) as the capping agent. The as-synthesized Meth-capped PbS QDs exhibited size-uniform, strong fluorescence emission (maximum emission at 510 nm) with 17.3 % quantum yield (QY) and robust photo- and time-stability. The resulting PbS QDs acted as a fluorescent probe for selective detection of As(III) in aqueous media. When As(III) ions were added to the QDs solution, the fluorescence intensity was effectively quenched, due to strong interaction between As(III) and Meth to form an S, N bidentate chelate ring. Under optimum conditions, a linear relationship between fluorescence quenching of the system and the concentration of As(III) was observed in the range of 5–150 ppb with a limit of detection of 3.7 ppb. It was less than the highest tolerable amount of As(III) ions (10 ppb) in drinking water, which is allowed by the World Health Organization (WHO). This proposed fluorescent method possesses good selectivity and high sensitivity, which can be applied in the rapid detection of As(III) in real water samples.

Application of synthesized 2,5-bis(allyloxy)terephthalohydrazide functionalized covalent organic framework material as a fluorescence probe for selective detection of mercury (II)

The mercury ion Hg2+ is a highly toxic environmental contaminant that threatens both the ecosystem and human health. As such, in recent years, significant effort has been invested in developing novel strategies for ultrasensitive detection of Hg2+. Herein, we leveraged the inherent benefits of covalent organic frameworks (COFs) to design a fluorescent COF with the ability to detect Hg2+, then synthesized a 2,5-bis(allyloxy)terephthalohydrazide functionalized COF material, called BATHz-Bt, for selective Hg2+ recognition. Unlike other methods that rely on sulfur-based ligands, BATHz-Bt is comprised of a π-conjugated framework that serves as the signal transducer; and compact, evenly distributed allyloxy groups that function as the Hg2+ acceptor. In addition to the benefits provided by a stable, COF structure, the material is also re-usable, making it reliable, cost effective, and eco-friendly. Furthermore BATHz-Bt showed good detection performance, as evidenced by its high sensitivity, good selectivity, excellent pH stability, and reusability. Moreover, X-ray photoelectron spectroscopy (XPS) confirmed the presence of a robust and selective interaction between the BATHz-Bt allyloxy groups and Hg2+. Thus, while this study demonstrates the application potential of fluorescent COFs for Hg2+ detection, more importantly, it also provides a new, simple approach to environmental monitoring using functionalized COFs.

A Novel Fluorescent Probe for Selective Detection of Hydrazine and Its Application in Imaging.

In this work, a novel fluorescent probe with first-time-selected thiazepine backbone, TZPzine-1, was developed for selective detection of hydrazine in water samples and living cells. Chosen from our recent anti-cancer agents, TZPzine-1 inferred structurally based advantages of the optical adjustability and the hydrazine-trapping approach. It also showed applicable properties including high sensitivity (LOD = 50 nM), wide linear range (0–15 equiv.), high selectivity (especially from competing species), rapid response (within 20 min), and practical steadiness in various pH (6.0–11.0) and temperature (15–50 °C) conditions. To satisfy the interdisciplinary requirements in environmental toxicology, TZPzine-1 was successfully applied in water samples and living cells. We hope that the information in this work, as well as the concept of monitoring the nitrogen cycle, may be referable for future research on systematic management.

Colorimetric “off–on” fluorescent probe for selective detection of toxic Hg2+ based on rhodamine and its application for in-vivo bioimaging

A novel “turn on” fluorimetric sensor 1-benzyl-N-(3',6'-bis(ethylamino)-2',7'-dimethyl-3-oxospiro[isoindoline-1,9'-xanthen]-2-yl)-7-hydroxy-5-oxo-1,2,3,5-tetrahydroimidazo[1,2-a]pyridine-8-carboxamide (RhB) based on rhodamine moiety has been designed and synthesized. The cation sensing ability of RhB was examined and validated using UV–visible, fluorescence, and NMR spectral studies. The probe RhB exhibits selective and sensitive sensing towards Hg2+ over the other competitive metal cations like Ag+, Al3+, Ba2+, Cu2+, Cd2+, Fe3+, Fe2+, K+, Li+, Mg2+, Mn2+, Pb2+, Ni2+, Na+, Zn2+ in EtOH:HEPES buffer solution (1:1, v/v) medium and a rapid 1:1 stoichiometric irreversible reaction were obtained between RhB and Hg2+. The UV–vis and fluorescence spectral changes suggest the effectiveness of the probe and the rapid response of RhB towards Hg2+ could be due to the formation of the coordinate bond between the ligand and metal. The spirolactam ring opening followed by the formation of suitable coordinate geometry in the RhB is the reason for the selective sensing of Hg2+ ion. NMR titration experiments further confirmed this. The binding constant was calculated by the B-H plot and found to be 4.0 × 109 M−1. The LOD for UV–vis and fluorescencebased detection was found to be 2.57 µM (0.516 mg L−1). Likewise, an economically feasible, easy-to-use test strips of RhB was developed for the naked-eye detection of Hg2+ in 100% aqueous solution. However, it was found to be much less sensitive than the spectrophotometric method. Further, in vivo experiments were performed using Drosophila melanogaster that led to demonstrate its efficacy at identifying mercury toxicity within an organism.

Zn-based complex as a fluorescent probe for selective detection of Fe3+ ion and treatment activity on the primary immune thrombocytopenia through regulating the PD-L1 expression

Zn-based complex as a fluorescent probe for selective detection of Fe3+ ion and treatment activity on the primary immune thrombocytopenia through regulating the PD-L1 expression

A simple fluorescent probe for selective detection of Al3+ based on furan Schiff base and its crystal structure

A simple “turn–on” fluorescent probe L was synthesized by condensation of furan-2-carbohydrazide and 2-hydroxy-4-methoxybenzaldehyde, and its structure was confirmed by single crystal X-ray diffraction. The probe L exhibited excellent selectivity towards Al3+ over other coexistent metal ions with remarkable fluorescence enhancement, accompanied by color change from colorless to blue. Moreover, the probe L showed high sensitivity to Al3+ with low detection limit (3.10 × 10−8 M) in the pH range of 3.0-8.0. The possible sensing mechanisms of L toward Al3+ were determined by Job plots experiments, high resolution mass spectrometry (HRMS), 1H NMR spectra and the density functional theory (DFT) calculations. Additionally, the probe L was successfully applied for detection of Al3+ in water samples with satisfactory results.

β-Cyclodextrin-capped ZnO-doped carbon dot as an advanced fluorescent probe for selective detection of dopamine

Selective and sensitive detection of dopamine in presence of other interfering biomolecules using β-cyclodextrin-capped ZnO-doped carbon dot.