Copper Sensor Research Articles

Application of 3D printed ABS based conductive carbon black composite sensor in void fraction measurement

The application range of fused deposition modeling (FDM) process has been increased by the introduction of multifunctional materials. These materials exhibit enhanced mechanical and thermal properties. In addition to that, some materials like graphene, carbon nanotubes and carbon black have the conductive properties and can be used in electronic applications. In this research work acrylonitrile butadiene styrene (ABS) based carbon black (CB) filament is used for three dimensional (3D) printing the low cost concave capacitive sensor and it is used to measure the void fraction of the two-phase flow. The capacitance values for different void fractions are measured using 3D printed sensor and compared with the copper sensor. Also, the effect of parameters such as thickness and width of sensors on capacitance values are studied, and a prediction model using regression analysis is developed and validated to find the void fraction value. Analysis of variance (ANOVA) is done to find the significant factors affecting the capacitance values obtained for different void fraction values.

Luminescent gold nanoparticles as dual-modality sensors for selective copper (II) ion detection

Ion sensors are important tools for the determination of metal ion concentrations in aqueous environments. Here we describe the synthesis of ca. 3 nm cysteamine and glutathione-coated luminescent gold nanoparticles (CG-AuNPs) using a one-pot mild reduction method; resulting nanoparticles were extensively characterized. Fluorescence spectroscopy and dynamic light scattering (DLS) measurements indicate the synthesized gold nanoparticles exhibit excellent stability at physiological pH and high ionic strength. We demonstrate that these nanoparticles can act as highly sensitive and selective dual-modality sensors of Cu2+ ions under physiologically-relevant conditions. Limits of detection were determined to be 18.2 nM (fluorescence) and 19.6 nM (DLS), respectively.

A naked-eye fluorescent sensor for copper(ii) ions based on a naphthalene conjugate Bodipy dye.

A novel naphthalene-Bodipy dye (N-Bodipy) was designed, prepared and characterized. N-Bodipy showed a selective and sensitive recognition toward Cu(ii) ions as a fluorescent antenna group in acetonitrile/water over other metal cations. The complexation between Cu(ii) ions and N-Bodipy gave a specific color change as well as caused fluorescence quenching under long-wavelength light (365 nm). The remarkable quenching effect in fluorescence intensity centered at 538 nm was only observed in the presence of copper(ii) ions. Moreover, the orange color of N-Bodipy solution turned pale-yellow depending on the complexation effect in daylight. The complex stoichiometry was determined using a Job's plot and it was found to be 2 : 1 (ligand/metal). The binding constant was calculated with the Benesi-Hildebrand equation to be 1.39 × 1010 M-1 and the detection limit was 1.28 μM (LOD = 3α/slope, α is the standard deviation) for Cu(ii). The data proved that the binding between N-Bodipy and Cu(ii) is chemically reversible.

A novel quinoline-based fluorescent sensor for imaging Copper (II) in living cells

A novel quinoline-based fluorescent sensor for imaging Copper (II) in living cells

Hand-held optical sensor using denatured antibody coated electro-active polymer for ultra-trace detection of copper in blood serum and environmental samples

An optimum copper concentration in environment is highly desired for all forms of life. We have developed an ultrasensitive copper sensor which functions from femto to micro molar concentration accurately (R2 = 0.98). The sensor is based on denatured antibody immunoglobulin G (IgG), immobilized on polyaniline (PAni) which in turn is the coating on the core of an optical fiber. The sensing relies on changes in evanescent wave absorbance in the presence of the analyte. The sensor showed excellent selectivity towards Cu (II) ions over all other metal ions. The sensor was tested with lake and marine water samples to determine unknown concentrations of copper ions and the recovery results were within 90–115%, indicating reasonable accuracy. We further integrated the fiber-optic sensor with a miniaturized hand-held instrumentation platform to develop an accurate and field deployable device which can broadly be applicable to determine Cu (II) concentration in a wide range of systems – natural water bodies, soil as well as blood serum.

Enhancing the robustness of microbial fuel cell sensor for continuous copper(II) detection against organic strength fluctuations by acetate and glucose addition

Microbial fuel cell sensors have shown great promise for continuous monitoring of toxic substances in wastewater, but a persistent problem is the signal interferences due to fluctuations in organic strength. An approach to eliminate the interferences is to saturate the sensor with an added organic substrate. In this study, signal stabilization using acetate and glucose addition (150, 300 and 500 mg COD/L) to domestic wastewater was examined. Addition of acetate (500 mg COD/L) gave the best performance, increasing the robustness of the sensor by reducing signal interference (decrease in baseline current) from 65% to 15% for a sudden 75% decrease in organic strength. The sensor sensitivity remained unchanged at current drop of 0.16%/(mg/L Cu(II)) for a toxicity event (300 mg/L Cu(II)). Addition of acetate (300 mg COD/L) and glucose (150, 300 and 500 mg COD/L) also resulted in increased robustness but led to a reduced sensitivity to Cu(II).

Ultrasound-electrospinning-assisted fabrication and sensing evaluation of a novel membrane as ultrasensitive sensor for copper (II) ions detection in aqueous environment

The present study has reported an optimized fabrication and application of a novel PVA/TEOS/Schiff base nanofibers membrane as a highly sensitive copper (II) ions in aqueous environment. Here in, for first time, an ultrasound-assisted synthesized symmetric Schiff base has been immobilized on a hybrid polyvinyl alcohol (PVA) and TEOS using electrospinning technique for detection and filtration of copper ions. For this purpose, various working parameters were evaluated and finally the optimized nano fibers membrane was synthesized with 72 nm thickness and PVA/TEOS/Schiff base ratio of (wt%) 8:6:1. The optimized sample named PTLNFM has been employed successfully as an ultra sensitive chemosensor for Cu (II) detection in real samples. The immobilized Schiff base used as a chelating agent could detect copper (II) in the range from 9.34 × 10−8 to 1.15 × 10−5 mol L−1 with the following correlation equation: Absorbance = 0.066 [Cu2+] × 10−6 + 0.095 and R2 = 0.992 and LOD of 1.27 × 10−8 mol L−1 which was lower than most of the reported detection limits in the previous literatures. Validity of this method has been carried out by analysis of Cu2+ in real samples with satisfying recoveries of over 96.11–99.24%.The developed membrane could be offered for diverse use such as medical or industrial applications.

Low symmetric metallophthalocyanine modified electrode via click chemistry for simultaneous detection of heavy metals

Beside different methods and materials used to develop electrochemical sensors, the modification of the electrode using click reaction based on metallophthalocyanine (MPc) compounds are shown to improve the stability and sensitivity of the sensor. This work reported the development of electrochemical sensor for mercury (II), Lead (II), copper (II) and cadmium (II) ions detection based on the synthesized novel low symmetry alkyne terminated cobalt Phthalocyanine (CoPc) derivative. Differential pulse stripping voltammetry (DPSV) technique was employed for the first time in simultaneous determination of trace levels of the above metal ions using modified glassy carbon electrode (GCE) via click chemistry. Under the optimum experimental conditions, the anodic peak current is proportional to the concentrations of metal ions over a wide range of 0 to 0.1 mM with nanolevel detection limit of 81.94, 327.71, 55.87 and 347.06 nM and the sensitivity of 866.23 ± 5.48, 215.82 ± 2.16, 1979.48 ± 11.47 and 204.50 ± 1.10 μA/mM for Hg(II), Cu(II), Pb(II) and Cd(II), respectively. The selectivity of the clicked-CoPc modified GCE toward Hg(II), Cu(II), Pb(II), Cd(II) present no interference from these metals ions. The fabricated electrochemical sensor exhibited very good electrochemical properties such as good reproducibility, stability, reusability and is suitable for the detection of heavy metal ions in tap water in our laboratory.

Gigital measuring equipment of meat water connection with copper electrode sensor based on microcontroller AT89S52

Meat moisture measuring devices can be made using microcontroller AT89S52 based copper electrode sensors. The workflow of the meat content measuring device begins with a copper sensor that detects the level of pork water, the voltage generated by the sensor is passed to the ADC. The voltage received is then converted into digital data in the form of meat content data measured by microcontroller AT89S52. The digital data obtained was then processed by microcontroller AT89S52 and the water content of pork, beef, and chicken meat was displayed on LCD 2x16. The results obtained from three meat samples were pork meat samples of 99.995%, beef samples of 99.994% and chicken meat samples of 99.994%. Keywords : ADC; Electrode; Meat water connection; Microcontroller; Sensor;

β-Carboline–imidazopyridine hybrids: selective and sensitive optical sensors for copper and fluoride ions

Two rationally designed β-carboline–imidazopyridine hybrid chromofluorescent sensors S1 and S2 have been successfully synthesized and evaluated for the selective sensing of metal ions and anions.

Tuning the Color Palette of Fluorescent Copper Sensors through Systematic Heteroatom Substitution at Rhodol Cores.

Copper is an essential nutrient for sustaining life, and emerging data have expanded the roles of this metal in biology from its canonical functions as a static enzyme cofactor to dynamic functions as a transition metal signal. At the same time, loosely bound, labile copper pools can trigger oxidative stress and damaging events that are detrimental if misregulated. The signal/stress dichotomy of copper motivates the development of new chemical tools to study its spatial and temporal distributions in native biological contexts such as living cells. Here, we report a family of fluorescent copper sensors built upon carbon-, silicon-, and phosphorus-substituted rhodol dyes that enable systematic tuning of excitation/emission colors from orange to near-infrared. These probes can detect changes in labile copper levels in living cells upon copper supplementation and/or depletion. We demonstrate the ability of the carbon-rhodol based congener, Copper Carbo Fluor 1 (CCF1), to identify elevations in labile copper pools in the Atp7a-/- fibroblast cell model of the genetic copper disorder Menkes disease. Moreover, we showcase the utility of the red-emitting phosphorus-rhodol based dye Copper Phosphorus Fluor 1 (CPF1) in dual-color, dual-analyte imaging experiments with the green-emitting calcium indicator Calcium Green-1 to enable simultaneous detection of fluctuations in copper and calcium pools in living cells. The results provide a starting point for advancing tools to study the contributions of copper to health and disease and for exploiting the rapidly growing palette of heteroatom-substituted xanthene dyes to rationally tune the optical properties of fluorescent indicators for other biologically important analytes.

A Brief Review on Fluorescent Copper Sensor Based on Conjugated Organic Dyes

The design and development of the fluorescence reporting molecules for the trace recognition of the metallic ions in the aqueous, mixed organic aqueous media, environmental specimen, living things e.g., body fluids, serum, urine etc is the evergreen research area. Among several methodologies utilized for these purposes, the fluorescent techniques have wonderful impact in the era of metal sensor development due to their acclamatory features of non-invasive detection process and appreciable sensitivity. The utilization of small organic molecules for the sensation of metallic ions through the fluorescent techniques harvested the wonderful results having some interesting features of chromogenic response on metal binding, robustness in the preparation and applicability to establish the metallic accumulation level inside the live cells via bioimaging studies. The detailed knowledge and background about the several reported chemosening strategies have the utmost importance in order to understand or to design the novel molecules for metal sensing purposes. The objective of the presents review was to compile the best ever used copper sensing strategies via fluorescent means in the running decade. We have summarized the values of optical positions of the spectral lines, spectral shifting upon metal binding, binding/association/dissociation constants, chromogenic changes in the reaction mixture, proposed complexation mechanism of the ligand with the copper, ligand sensitivities toward the copper recognition, binding stoichiometries and the detailed bioimaging results where applicable.

Facile Synthesis of Fluorescent Conjugated Polyelectrolytes Using Polydentate Sulfonate as Highly Selective and Sensitive Copper(II) Sensors.

Fluorescent conjugated polyelectrolytes represent an exciting area of research into new chemosensors. By virtue of their rapid electron and energy transfer paths, these highly correlated, one-dimensional systems have been depicted as "molecular wires" and show "million-fold" sensitivity compared to monomolecular sensor analogs. In this paper, a novel polyelectrolyte sensor, the ttp-PPESO3, has been designed by incorporating terpyridine and sulfonate functional groups into the polyelectrolyte. This specifically tailored sensor has displayed remarkable quenching response toward copper(II) with a detection limit of 14.7 nM (0.93 ppb). It is capable of selectively screening copper without interference from 12 common cations. Molecular modeling suggests that binding occurs through a coordination interaction of the terpyridine and sulfonate. The additional multidentate nature from the sulfonate offers extraordinary chelating ability to the analyte. We anticipate that this unique binding mode will provide insight for the design of future more sensitive and selective systems.

A novel fluorene-derivative Schiff-base fluorescent sensor for copper(II) in organic media

Abstract A new Schiff-base sensor containing fluorene was synthesized and investigated for determination of metal ions in dimethylsulfoxide solutions. Fluorescence was quenched upon coordination, showing selectivity for Cu(II) over Mn(II), Fe(III), Ni(II), Pd(II), Zn(II), Ca(II), Hg(II), Na(I) and K(I) in a concentration range of 1.00 to 10.0 × 10 ‐7 mol L ‐1 . Good results were observed for sensor 1 derived from 2‐formylpiridine. Benesi‐Hilderbrand formalism indicates that the most abundant species formed have 2:1 (metal/ligand) ratio with a calculated biding constant of 1.74 × 10 12 L 2 mol −2 in good agreement with the Stern‐Volmer constant K SV at 2.26 × 10 12 L 2 mol −2 . The limit of detection ( LOD ) for Cu(II) was found to be 0.037 μmol L −1 with a relative standard deviation ( RSD ) of 3.19% in the copper(II) concentration range of 3.00 to 7.00 × 10 −7 mol L ‐1 .

Cell-surface copper transporters and superoxide dismutase 1 are essential for outgrowth during fungal spore germination

During fungal spore germination, a resting spore returns to a conventional mode of cell division and resumes vegetative growth, but the requirements for spore germination are incompletely understood. Here, we show that copper is essential for spore germination in Schizosaccharomyces pombe Germinating spores develop a single germ tube that emerges from the outer spore wall in a process called outgrowth. Under low-copper conditions, the copper transporters Ctr4 and Ctr5 are maximally expressed at the onset of outgrowth. In the case of Ctr6, its expression is broader, taking place before and during outgrowth. Spores lacking Ctr4, Ctr5, and the copper sensor Cuf1 exhibit complete germination arrest at outgrowth. In contrast, ctr6 deletion only partially interferes with formation of outgrowing spores. At outgrowth, Ctr4-GFP and Ctr5-Cherry first co-localize at the spore contour, followed by re-location to a middle peripheral spore region. Subsequently, they move away from the spore body to occupy the periphery of the nascent cell. After breaking of spore dormancy, Ctr6 localizes to the vacuole membranes that are enriched in the spore body relative to the germ tube. Using a copper-binding tracker, results showed that labile copper is preferentially localized to the spore body. Further analysis showed that Ctr4 and Ctr6 are required for copper-dependent activation of the superoxide dismutase 1 (SOD1) during spore germination. This activation is critical because the loss of SOD1 activity blocked spore germination at outgrowth. Taken together, these results indicate that cell-surface copper transporters and SOD1 are required for completion of the spore germination program.

Luminescent AIZS-GO nanocomposites as fluorescent probe for detecting copper (II) ion

A selective copper (II) sensor based on graphene oxide (GO) modified Ag-In-Zn-S (AIZS) quantum dots (QDs) was proposed. The fluorescence of the water-soluble AIZS QDs was quenched after addition of Cu2+ ion, which was triggered by the aggregation of the QDs in the form of R-COO-(Cu2+)-OOC-R, as verified by the TEM and FTIR. The fluorescence probe can be applied to detect Cu2+ ion in a wide concentration range of 0-850 μM based on the degree of fluorescence quenching, with its limitation of detection (LOD) and R2 of 0.18μM and 0.99, respectively. Moreover, the nanosensor can distinguish Cu2+ ion from other ions, offering great potentials in copper (II) determination in drinking water.

A fast, highly selective and sensitive dansyl-based fluorescent sensor for copper (II) ions and its imaging application in living cells

Since the copper ions (Cu2+) play a fatal role in many foundational physiological processes, it is important to develop a simple, highly sensitive and selective sensor for Cu2+ detection in living systems. Herein, an intramolecular charge transfer (ICT) and dansyl-based fluorescent chemosensor 1 was designed, synthesized and characterized for the sensitive and selective quantification of Cu2+. It exhibited remarkable fluorescence quenching upon addition of Cu2+ over other selected metal ions, attributed to the complex formation between 1 and Cu2+ with the association constant 6.7×105M−1. The sensor 1 showed a fast and linear response towards Cu2+ in the concentration range from 0 to 12.5×10−6molL−1 with the detection limit of 2.5×10−7molL−1. This detection could be carried out in a wide pH range of 5.0–14. Furthermore, sensor 1 can be used for detecting Cu2+ in living cells.

Highly sensitive and selective fluorescent sensor for copper(ii) based on salicylaldehyde Schiff-base derivatives with aggregation induced emission and mechanoluminescence

The present study provides valuable information for designing materials with AIE, Cu2+ sensor and MFC properties based on Schiff-bases.

Hybrid graphene–copper UWB array sensor for brain tumor detection via scattering parameters in microwave detection system

Hybrid graphene–copper ultra-wideband array sensor applied to microwave imaging technique is successfully used in detecting and visualizing tumor inside human brain. The sensor made of graphene coated film for the patch while copper for both the transmission line and parasitic element. The hybrid sensor performance is better than fully copper sensor. Hybrid sensor recorded wider bandwidth of 2.0–10.1 GHz compared with fully copper sensor operated from 2.5 to 10.1 GHz. Higher gain of 3.8–8.5 dB is presented by hybrid sensor, while fully copper sensor stated lower gain ranging from 2.6 to 6.7 dB. Both sensors recorded excellent total efficiency averaged at 97 and 94%, respectively. The sensor used for both transmits equivalent signal and receives backscattering signal from stratified human head model in detecting tumor. Difference in the data of the scattering parameters recorded from the head model with presence and absence of tumor is used as the main data to be further processed in confocal microwave imaging algorithm in generating image. MATLAB software is utilized to analyze S-parameter signals obtained from measurement. Tumor presence is indicated by lower S-parameter values compared to higher values recorded by tumor absence.

Design and construction of electrochemical selective sensors for copper(II) in water samples based on C18H18N6S2 and C4H8O4S2 Dithio ligands as neutral carriers

Design and construction of electrochemical selective sensors for copper(II) in water samples based on C18H18N6S2 and C4H8O4S2 Dithio ligands as neutral carriers