Probe For Detection Of Fe3 Research Articles

Rhodamine B- and coumarin-modified chitosan as fluorescent probe for detection of Fe3+ using quenching effect

Rhodamine B- and coumarin-modified chitosan as fluorescent probe for detection of Fe3+ using quenching effect

Preparation of temperature-responsive nanomicelles with AIE property as fluorescence probe for detection of Fe3+ and Fe2+

Temperature-responsive nanomicelles with aggregation induced emission (AIE) property were prepared by the host–guest complexation of ferrocene functionalized tetraphenyl (TPE-Fc) and β-cyclodextrin-poly (N-isopropylacrylamide) (β-CD-(PNIPAM)7). The AIE chromophore TPE-Fc bound to the hydrophobic cavity of cyclodextrin serves as the core of micelles, and temperature sensitive PNIPAM serves as the shell to give the micelles good solubility. The size of the nanomicelles is about 100 nm. At the excitation wavelength of 340 nm, the strongest fluorescent emission peak was 421 nm. The introduction of cyclodextrin star polymer increased the fluorescence intensity of nanomicelles, thus improving the recognition of probe to Fe3+ and Fe2+. The fluorescent probe can quickly detect Fe3+ and Fe2+ in water within 5 min even in the presence of various interfering ions. The detection limits of Fe3+ and Fe2+ were 1.04 μM and 0.78 μM, respectively in the range of 10–90 μM. The formation of complex between the probe and Fe3+/Fe2+ was supported by Job’s plot. The probe was successfully applied to the detection of Fe3+and Fe2+ in actual water sample with a good recovery. In addition, a possible sensing mechanism for the interaction of iron ions with amide bond groups of nanomicelles was proposed.

Design, synthesis and biological evaluation of novel dual-targeting fluorescent probes for detection of Fe3+ in the lysosomes of hepatocytes mediated by galactose-morpholine moieties

In this work, novel dual-targeting probes composed of galactose and morpholine were designed and synthesized for monitoring Fe3+ levels in the lysosome of hepatocyte. MP-Gal-1, MP-Gal-2 and MP-Gal-3 showed good selectivity and sensitivities toward Fe3+ with the detection limits of 9.40 × 10−8 M, 7.68 × 10−8 M and 7.10 × 10−8 M, respectively. 1:2 stoichiometry is the most likely recognition mode between probe and Fe3+. Low toxic MP-Gal-1, MP-Gal-2 and MP-Gal-3 exhibited favorable hepatic targeting effect in both cell and tissue levels, which was because the galactose group of probe could be recognized by ASGPR overexpressed on the hepatocytes. The hepatocyte-targeting capacity followed MP-Gal-1 < MP-Gal-2 < MP-Gal-3 trend, which was attributed to the galactose cluster effect. MP-Gal-1, MP-Gal-2 and MP-Gal-3 also displayed good lysosomes-targeting capacities, because the basic morpholine moiety of probes could be easily attracted by the acidic lysosome. Therefore, MP-Gal-1, MP-Gal-2 and MP-Gal-3 have good dual targeting capacities (liver and lysosome) and could be used to detect lysosomal Fe3+ in the liver, which is great significant for precise diagnosis and treatment of liver lysosomal iron-related diseases.

Facile approach for green synthesis of fluorescent carbon dots from Manihot esculenta and their potential applications as sensor and bio-imaging agents

An eco-friendly approach for the synthesis of blue fluorescent carbon dots (CDs) using Manihot esculenta with an average size of 3–5 nm through hydrothermal method has been reported. Functionality of the prepared CDs was characterized by FT-IR spectroscopy. Structural and morphological characterisation were carried with XRD and TEM techniques, these studies exposed amorphous nature of carbons dots with spherical shape. Optical properties of CDs were examined using UV–Visible and Photoluminescence spectral techniques. Owing to strong blue fluorescence, CDs were evaluated for its ability to sense various heavy metal ions. Attributable to significant response towards Fe3+ ions among different metal ions tested (Al3+, Cu+, Co2+, Pb2+, Zn2+, Fe3+, Ca2+, Hg2+ and Mg2+), CDs were used as a selective fluorescence probe for detection of Fe3+. The bioimaging and cytotoxicity aspects of CDs on MDA MB-231 breast cancer cell lines were confirmed by localised experiments. The synthesised CDs were found to be non-toxic even at their high concentration of 500 µg/mL.

High-yield production of g-C3N4 quantum dots as photocatalysts for the degradation of organic pollutants and fluorescent probes for detection of Fe3+ ions with live cell application

Graphitic-carbon nitride quantum dots (gCNQDs) have various fascinating properties and potential applications, but the low yield production of gCNQDs by current synthetic methods severely limits to exploit their properties and large-scale applications. Here we report the large scale synthesis of uniform gCNQDs through a combination of hydrothermal treatment, sintering and sonication methods for the first time. The production yield is up to 39 %, and the obtained gCNQDs dry powder possesses outstanding redispersibility, stability and water solubility in deionized water. The gCNQDs aqueous suspensions emit bright blue luminescence under UV excitation and can be an effective fluorescence probe for Fe3+ detection with good selectivity, sensitivity and photostability. The fluorescent probe shows low cytotoxicity and good cell-permeability, and then being successfully applied for the fluorescence imaging of Fe3+ in living cells. Moreover, the gCNQDs show the improved photocatalytic activity, which was evaluated by degradation of Rhodamine B and Methyl Orange. The large scale synthesis of gCNQDs with outstanding fluorescent properties, biocompatibility and photocatalytic properties can effectively facilitate the applications of gCNQDs and gCNQDs based nanocomposites in various fields.

N-doped red emission carbon dots and detection of Fe3+

So far, the fluorescence emission wavelength of carbon dots has been mostly concentrated in the blue-green area, while the number of carbon dots which emit red light is small. However, carbon dots with long wavelength emission are urgently needed in the many fields such as biological imaging and detection. Here, we synthesized an N-doped red emission carbon dots (r-CDs) by a simple, green hydrothermal method in one step. The prepared carbon dots have many superior properties such as high alcohol solubility, emission independent of excitation, high stable optical property and highly sensitive and selective to Fe3+. Dispersed the r-CDs into the ethanol, the fluorescence emission spectrum of the r-CDs showed red emission with a main peak at 600 nm and a shoulder peak at 640 nm. And the QY of the r-CDs is 7.1 %. Through various structural characterization methods, the red emission was attributed to the surface state emission caused by a large number of N-containing functional groups on the surface. The r-CDs are selective to Fe3+ and have good sensitivity to Fe3+ within a certain concentration of 5—120 mmol/L. The r-CDs can be used as an unmodified detection probe for Fe3+. More importantly, the r-CDs were successfully used as a probe for the rapid detection of Fe3+ in tap water and got good detection results.

Nitrogen-doped graphene quantum dots synthesized by femtosecond laser ablation in liquid from laser induced graphene

In this work, graphene quantum dots (GQDs) were synthesized by femtosecond laser ablation in liquid using laser induced graphene as the carbon source. Nitrogen-doped graphene quantum dots (N-GQDs) were successfully synthesized by adding ammonia water to the graphene suspension. The GQDs/N-GQDs structure consist of a graphitic core with oxygen and nitrogen functionalities with particle size less than 10 nm, as demonstrated by x-ray photoelectron spectroscopy, Fourier infrared spectrometer spectroscopy, and transmission electron microscopy. The absorption peak, PL spectrum, and quantum yield of the N-GQDs were significantly enhanced compared with the undoped GQDs. Further, the possible mechanism of synthesis GQDs was discussed. Furthermore, the N-GQDs were used as a fluorescent probe for detection of Fe3+ ions. The N-GQDs may extend the application of graphene-based materials to bioimaging, sensor, and photoelectronic.

Photothermal-enhanced peroxidase-like activity of CDs/PBNPs for the detection of Fe3+ and cholesterol in serum samples

Carbon dots/Prussian blue nanoparticles (CDs/PBNPs) with fluorescence (FL) performance and peroxidase-like activity are synthesized by a simple two-step method. The FL of CDs/PBNPs can be effectively quenched by Fe3+. Fe3+ can accelerate the peroxidase-like activity of CDs/PBNPs. More excitingly, the peroxidase-like activity of CDs/PBNPs could be further enhanced due to the influence of thephotothermal effect. Based on the FL property and enhanced peroxidase-like activity, a cascade strategy is proposed for detection of Fe3+ and free cholesterol. CD/PBNPs act as FL probe for detection of Fe3+. Theenhanced peroxidase-like activity of CDs/PBNPs can also be used as colorimetric probe for the detection of free cholesterol. The detection ranges of Fe3+ and free cholesterol are 4-128μM and 2-39μM, and the corresponding limit of detections are 2.0μM and 1.63μM, respectively. The proposedstrategy has been verified by the feasibility determination of Fe3+ and free cholesterol, suggesting its potential in the prediction of disease.

Highly fluorescence Ta4C3 MXene quantum dots as fluorescent nanoprobe for heavy ion detection and stress monitoring of fluorescent hydrogels

Compared with other transition metal Mxene derived quantum dots (MQDS), Ta-based Mxene quantum dots have good functionality, but Ta-based Mxene quantum dots and their applications have not been studied so far. In this paper, we report for the first time the synthesis of high fluorescence quantum yield (QY) N-doped Ta4C3 quantum dots (N-MQDs) using Ta4C3 quantum dots in acid reflux damaged Ta4C3 nanosheets as precursors and ethylenediamine as nitrogen source. The prepared N-MQDs have excellent blue photoluminescence (PL) properties, particle size is only 2.60 nm, QY is up to 23.4%, and good stability. In addition, it has been reported that N-MQDs can be used as fluorescent probe for detection of Fe3+ and remote force sensing analysis In liquid ion sensing, N-MQDS shows a unique selective quenching of Fe3+ with a detection limit as low as 2 µmol/L, and has great potential as a fast and super-sensitive fluorescent probe for the detection of heavy ion. More importantly, in solid mechanics sensing, the introduction of N-MQDs into self-healing hydrogels can be developed into a fluorescent hydrogel that can be used for accurate remote force measurement and applied in the field of mechanical sensing analysis. Therefore, Ta-based N-MQDs show excellent potential in the field of fluorescence sensing, which provides a door for multi-dimensional sensing of new materials in the future.

A novel coumarin-based pyrazoline fluorescent probe for detection of Fe3+ and its application in cells

A novel coumarin-based pyrazoline fluorescent probe A was synthesized through a four-step reaction. The structure was characterized by 1H NMR(Nuclear magnetic resonance), 13C NMR and HR-ESI-MS(High resolution electrospray ionization mass spectrometry). The optical properties of the fluorescent probe was investigated by UV–vis absorption and fluorescence emission spectra. The results showed that the addition of Fe3+ makes the fluorescence emission spectra of A quenched and displayed a linear fluorescence response to Fe3+ with a detection limit of 1.01 × 10−7 M. It also shows good reversibility upon addition of EDTA(Ethylene diamine tetraacetic acid). The structure of the fluorescent probe was optimized by DFT(Density functional theory) calculations, and the binding mechanism between the fluorescent probe and the recognition ion was explained. Moreover, the probe also has practical application in cell imaging.

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 novel dehydroabietic acid-based fluorescent probe for detection of Fe3+ and Hg2+ ions and its application in live-cell imaging

A novel dehydroabietic acid-based fluorescent probe (DBH) containing 2,4-diarylbenzimidazole moiety was designed and synthesized, and the compound was characterized by its UV–Vis, FT-IR, 1H NMR, 13C NMR and ESI-MS spectra. DBH could be used for the detection of Fe3+ and Hg2+ through the selective fluorescence quenching in EtOH/H2O solution. The probe DBH showed excellent selectivity and sensitivity towards Fe3+ and Hg2+ over other metal ions. The limits of detection were calculated as 3.12 × 10−8 M and 3.10 × 10−8 M, respectively. Especially, DBH have a wide pH range for ion detection (5 ~ 12), and a short response time (10 s). Job’s plot method in combination with ESI-MS and FT-IR spectra was used to determine the stoichiometry of DBH-Fe3+/Hg2+ complexes as both 2:1. Moreover, DBH exhibited low cytotoxicity to MCF-7 and SMCC-7721 cells (IC50 > 100 μM). In the fluorescent cell imaging experiments, DBH could be used as a prominent intracellular probe for the detection of Fe3+ and Hg2+ in living cells.

High-Yield Production of Water-Soluble MoS2 Quantum Dots for Fe3+ Detection and Cell Imaging.

Uniform water-soluble MoS2 quantum dots (WS-MSQDs) were synthesized via a sequential combination of sintering/etching/exfoliation method and solvothermal route. The obtained WS-MSQDs with average size of approximately 3.4 nm exhibited sufficient water solubility and remarkable fluorescence properties. The WS-MSQDs were utilized as a probe for detection of Fe3+ ions with high selectivity and specificity. Furthermore, the WS-MSQDs exhibited high fluorescence stability under different conditions. Finally, the WS-MSQDs were successfully applied for the fluorescence imaging of Fe3+ in living cells, which exhibited practical potential for biomedical applications.

Study on the Development of a Cyclohexane Based Tripodal Molecular Device as "OFF-ON-OFF" pH Sensor and Fluorescent Iron Sensor

Background: Iron is an essential transition metal which is indispensable for life processes like oxygen transport and metabolism, electron transfer etc. However, misregulated iron is responsible for disease like anemia, hemochromatosis, Alzheimer’s and Parkinson’s disease. In order to encounter these diseases, a better understanding is needed of its role in misregulation. Fluorescent iron sensors could help provide this information. The new chemosensor developed by linking a cyclohexane unit with three 8-hydroxyquinoline provides selective detection of iron in numerous biological and environmental samples. Methods: The Uv-visible and fluorescence spectroscopy in combination with pH measurements will mainly be used for the study. Theoretical studies at DFT level will be used to validate the method and explain the theory behind the experiments. Results: The study of electronic spectra of the chelator, HQCC, reveals the appearance of a band at 262 nm along with a weak band at 335 nm due to π- π* and n- π* transitions respectively. Upon excitation with 335 nm, the ligand fluoresces at 388 nm wavelength. The intensity of the emission was affected in presence of metal ions, with maximum deviation for Fe(III). Selectivity studies showed that Fe(III) is more selective as compared to the biologically relevant metal ions viz., Al(III), Fe(III), Cr(III), Co(II), Fe(II), Ni(II), Zn(II), Cu(II), Mn(II) and Pb(II). pH dependent studies implied that the fluorescence intensity was highest at pH ~8.0, whereas maximum quenching for iron-HQCC system was observed at pH 7.4. The binding studies from the B-H plot confirms the formation of 1:1 complex with association constant of 5.95 × 106. The results obtained from experiments were in agreement with that obtained from the DFT and TD-DFT studies. Conclusion: A novel tripodal chelator based on 8-hydroxyquinoline and symmetric cyclohexane scaffold was successfully developed. In addition to the excellence of the ligand to be employed as a promising sensitive fluorescent probe for easy detection of Fe3+ions at the physiological pH with very low concentration (7.5 x 10-5 molL-1), the new ligand can be used as an OFF-ON-OFF pH sensor. Fe(III) encapsulation along with 1:1 ML-complexation formation have been established. Theoretical studies confirm a d-PET mechanism for the fluorescence quenching. DFT studies revealed that the neutral form of the ligand is less reactive than its protonated or the deprotonated form.

A ‘on-off-on’ fluorescent probe for sensitive detection of Fe3+ and ascorbic acid by cross-linking agent protected carbon dots

ABSTRACT Carbon dots (CDs) have gained great attention as multifunctional materials because of their interesting properties and general applicability. Herein, new CDs were synthesised from a facile hydrothermal treatment of cysteine and ethylene glycol dimethacrylate as both carbon and nitrogen source and cross-linking agent with high quantum yield (47.2%), respectively. The as prepared CDs were used to detect Fe3+ and ascorbic acid. The fluorescence intensity of CDs was selectivity quenched by Fe3+ in the range of 0.03–15.0 µM, with a detection limit of 10.2 nM. Meanwhile, ascorbic acid was found to reduce Fe3+ to Fe2+, thereby causing restoration of the fluorescence of CDs. The detection limit for ascorbic acid detection was estimated as 54.3 nM over a linear range from 0.1 to 25.0 µM. Furthermore, the designed sensing platform was successfully utilised to the detection of Fe3+ and ascorbic acid in water and fruits samples.

A highly selective fluorescent chemosensor probe for detection of Fe3+ and Ag+ based on supramolecular assembly of cucurbit[10]uril with a pyrene derivative

A new fluorescent probe composed of cucurbit[10]uril (Q[10]) and a water-soluble derivative of pyrene, aminopropyl-1-pyrenebutanamide (PBA), is designated. 1H NMR spectroscopy reveals that PBA is encapsulated into Q[10] in an aqueous solution to form a stable 1:1 host-guest inclusion complex of PBA@Q[10]. This complex behaves as a highly selective fluorescence quenching probe for Fe3+ in aqueous solutions that may be attributed to the efficient absorption of Fe3+, which hindering absorption of PBA@Q[10] probe at the excitation wavelength of 332 nm, and competitive experiments for the coexistence of Fe3+ with one or all of the other metal ions (37 metal ions) reveals that the selectivity of PBA@Q[10] to Fe3+ is not disturbed by the addition of 50.0 equiv. of the other metal ions. The limits of detection of Fe3+ was determined to be 0.55 mM. Furthermore, the fluorescence enhancing effect of PBA@Q[10] for Ag+ is detected at the above wavelength. According to the mechanistic studies, the fluorescence enhancing route involves interaction of Ag+ ions with the probe, mainly under an internal charge transfer between Ag+ and the probe. Outcomes of this study suggest that PBA@Q[10] probably functions as a potential and promising fluorescence sensor for monitoring of different polluting metal ions in waste waters.

Carbon dots derived from lychee waste: Application for Fe3+ ions sensing in real water and multicolor cell imaging of skin melanoma cells.

Exploit of biomass as an inexhaustible resource has accepted much more curiosity to the present research world. Herein, a simple, one-step solvothermal action has been used to synthesize an ascendable amount of fluorescent carbon dots (CDs) with an average size of~3.13 nm, from Low-reasonable and green source lychee waste. The excitation/emission maxima of CDs have 365/443 nm with high quantum yield (23.5%). The present ingredient predominantly contained carboxylic acid and hydroxyl group that acted as a passive agent for stabilizing the CDs. The structural and optical properties were evaluated through HRTEM, FTIR, UV-vis, zeta potential, XPS, fluorescence, and fluorescence lifetime experiments. We investigated the manoeuvre of our synthesized CDs as a probe for detection of Fe3+ ions in water bodies; This sensing approach showed impressive selectivity and sensitivity towards Fe3+ions with LOD 23.6 nM. The sensing mechanism took place through static quenching which was entrenched through fluorescence lifetime measurements. Fe3+ ions detection was basically carried out with efficacy in real water. For its lofty Photo-stability, low cytotoxicity and cell viability the probe were substantially applied for bio-imaging experiment i.e. intracellular multi-color cell imaging in skin melanoma cells (A375 cells) with and without Fe3+ ions exemplifying its real applications in living cells.

ZnMOF-74 responsive fluorescence sensing platform for detection of Fe3+

Fluorescent metal-organic frameworks (MOFs) have attracted wide attention in fluorescence detection. Herein, a novel sensing platform for highly selective and sensitive detection of Fe3+ in aqueous solution was proposed based on 2,5-dihydroxyterephthalic acid (DOBDC)-Zn2+ MOFs (ZnMOF-74). The as-prepared ZnMOF-74 exhibited uniform clavicorn nanostructures and high day-to-day stability in acidic aqueous solution (pH 4.0). Because of the special response of phenolic hydroxyl groups of DOBDC with Fe3+, the cation exchange between Fe3+ and Zn2+ occurred, which caused collapse of the skeleton and formed a blue weak-fluorescent iron(III)-phenol salt complex (Fe-DOBDC), which led to the effective fluorescence quenching of ZnMOF-74. ZnMOF-74 was used as a probe for detection of Fe3+ under relatively acidic condition with a good linear range of 0.1–100 μM and a low detection limit of 40 nM. The fluorescence probe was also applied to determine Fe3+ in real river water and human serum with good recovery and accuracy. This work provided a good Fe3+ sensor based on ZnMOF-74 due to high affinity between phenolic hydroxyl group and Fe3+.

Highly Sensitive and Selective Fluorescent Probe for Detection of Fe3+ Based on Rhodamine Fluorophore.

A simple rhodamine-based fluorescent probe L1, which exhibits good response to Fe3+ in CH3CN/Tris-HCl buffer (v:v = 9:1, pH7.00) solution. With the experimental conditions optimized, the probe L1 could be used as a fluorescent and colorimetric probe for Fe3+ with the detection limit as low as 0.29μM. The binding constant (Ka) of Fe3+ binding to the probe L1 were calculated to be 1.4 × 1010M-2, respectively from a Benesi-Hildebrand plot. With the addition of Fe3+, the CH3CN/Tris-HCl buffer (v:v = 9:1, pH7.00) solution of the probe L1 exhibited a obviously color change from transparent to pink with distinctive changes. More importantly, the recognition process of the probe L1 for Fe3+ was chemically reversible on the addition AcO-. Graphical Abstract.

Reversible “turn-off-on” fluorescence response of Fe(III) towards Rhodamine B based probe in vivo and plant tissues

A Fe3+-specific probe (N-TC) based on Rhodamine B was designed and synthesized. N-TC has a good spectral response to Fe3+ in the EtOH/H2O solution (1:1, v/v, HEPES, 0.5 mM, pH = 7.38) with low detection limits and high binding constants. N-TC displays the reversible “turn-off-on” fluorescence response with 1:1 binding stoichiometry. It is further proven to be practical in sensitively monitoring trace Fe3+ in environmental water specimens. Biological experiments demonstrated that N-TC can be respectively used as a probe for detection of Fe3+ in living cells, animals and plant tissues.