Detection Of Cu2 Research Articles

Heterocyclic fluorescent Schiff base chemosensors for the detection of Fe(III) and Cu(II) ions.

Two new Schiff bases were synthesized from 1-(2,4-dihydroxyphenyl)ethanone and pyridine derivatives. Both compounds were characterized using infrared, UV-Vis., 1H NMR, 13C NMR and mass spectral studies. Density functional theory (DFT) calculations were performed for both the Schiff bases with 6-31G(d, p) as the basis set. Vibrational frequencies calculated using the theoretical method were in good agreement with the experimental values. Both the Schiff bases were highly fluorescent in nature. The cation-recognizing profile of the compounds was investigated in aqueous methanol medium. The Schiff base 4-(1-(pyridin-4-ylimino)ethyl)benzene-1,3-diol (PYEB) was found to interact with Fe(III) and Cu(II) ions, whereas the Schiff base 4,4'-((pyridine-2,3-diylbis(azanylylidene))bis(ethan-1-yl-1-ylidene))bis(benzene-1,3-diol) (PDEB) was found to detect Cu(II) ions. The mechanism of recognition was established as combined excited state intramolecular proton transfer (ESIPT)-chelation-enhanced fluorescence (CHEF) effect and chelation-enhanced quenching (CHEQ) process for the detection of Fe(III) and Cu(II) ions, respectively. The stability constant of the metal complexes formed during the sensing process was determined. The limit of detection for Fe(III) and Cu(II) ions with respect to Schiff base PYEB was found to be 1.64 ×10-6 and 2.16 ×10-7M, respectively. With respect to Schiff base PDEB, the limit of detection for Cu(II) ion was found to be 4.54 ×10-4M. The Cu(II) ion sensing property of the Schiff base PDEB was applied in bioimaging studies for the detection of HeLa cells.

A green reaction-based turn-off fluorescence sensor for determination of copper ions: DFT calculations, quenching mechanism, green chemistry metrics, and application in environmental samples.

When Cu(II) reacts with ascorbic acid (AA) to form Cu(I), Cu(I) can combine with eosin Y (EY) to form ionic associations, resulting in significant fluorescence quenching of the EY. Based on the turn-off of fluorescence in the chemosensor EY, a green reaction is proposed herein for the detection of Cu(II). The novel detection method for Cu(II) demonstrates simplicity, high sensitivity, and excellent selectivity, rendering it suitable for analyzing environmental samples. A static fluorescence quenching mechanism is validated through the Stern-Volmer relationship, and the thermodynamic parameters of the reaction are explored using a van 't Hoff plot. The reaction mechanism is investigated via fluorescence spectra, absorption spectra, and density-functional theory (DFT) calculations. The probe's green nature is confirmed by applying four green analytical chemistry metrics.

Synthesis and Application of 1,8-Naphthalimide Derivatives Fluorescent Probe for Sequential Recognition of Cu2+ and H2PO4.

A naphthalimide Schiff base fluorescent probe (BSS) was designed and synthesized from 4-bromo-1,8-naphthalic anhydride, and its structure was characterized by 1HNMR, 13CNMR, FTIR, and MS. Fluorescence emission spectra showed that probe BSS could realize the "turn-off" detection of Cu2+ in acetonitrile solution, detection process with strong specificity and excellent anti-interference of other metal ions. In the fluorescence titration experiments, fluorescence intensity of BSS showed a good linear relationship with the Cu2+ concentration (0-10 µmol/L), and the detection limit was up to 7.0 × 10- 8 mol/L. Meanwhile, BSS and Cu2+ could form a 1:1 complex (BSS-Cu2+) during the reaction process. Under the same detection conditions, complex BSS-Cu2+ had specific fluorescence recovery properties for H2PO4- and the whole process was not only fast (6s) but also free of interference from other anions, with a detection limit was as low as 5.7 × 10- 8 mol/L. In addition, complex BSS-Cu2+ could be successfully applied to the detection of H2PO4- in actual water samples, which with excellent application prospects.

Detection of copper in tea and water sample: A click-oriented azomethine-based 1,2,3-triazole fluorescent chemosensor with reversible INHIBIT logic gate behavior and computational aspects

A fluorescent azomethine-scaffolded-1,2,3-triazole linked chemosensor was synthesized utilizing alkyne and azidomethylbenzene via Cu(I)-catalyzed click chemistry. The compounds (3–5 and L6) were analyzed using FTIR, 1H NMR, 13C NMR, and GCMS–. The exploration of ion sensing ability of L6 complex, using UV–Vis and fluorescence spectroscopy in ACN:H2O (4:1) medium resulted in detection of Cu(II) ions, exclusively. Further L6-Cu(II) complex was characterized via FTIR, FE-SEM, LCMS and supported by DFT studies. A significant structural modification has rendered the current probe as highly selective for Cu2+ ions, with ‘Turn-On’ response. The chemical receptor (L6) establishes 1:1 molar ratio with Cu(II) ions with binding constant of 6.0 × 104 M−1 and excellent detection limit of 20 nM. In addition, the sensitive reversible behavior of probe (L6) with two chemical inputs (Cu2+ and EDTA) contributes to the construction of an INHIBIT logic circuit. The Copper ion detection was effectively monitored for real-world samples like Black Tea with precise quantification of Copper(II) ions.

α-Naphtholbenzein based heterocyclic sensor for detection of Cu(II) ions

Present research work illustrates the ‘Click’ generation of 4-((1-((1-benzyl-1H-1,2,3-triazol-4-yl) methoxy) naphthalen-4-yl) (phenyl)methylene) naphthalen-1(4H)-one α-NBT, a heterocyclic compound analyzed as an optical chemosensor for the selective detection of Cu(II) ions. The molecule is synthesized by [3 + 2] cycloaddition reaction of α-naphtholbenzein based terminal alkyne 2 with 1-(azidomethyl) benzene 3 under Cu(I)-catalyzed conditions (CuAAC) and is further characterized for its structural components by various spectroscopic techniques like IR, NMR (1H, 13C) and Mass spectrometry. Being having significant absorption in UV–Visible region, the receptor molecule α-NBT is analyzed for its chemosensing characteristics by UV–Visible and fluorescence spectroscopy and found to be very selective towards Cu(II) ions among a range of metal ions including Na(I), K(I), Ba(II), Cr(III), Mn(II), Fe(II), Fe(III), Co(II), Ni(II), Cu(I), Zn(II), Cd(II), Hg(II), Pb(II), Th(IV) and Ce(III) in CH3CN:H2O (4:1, v/v) solvent system. From the recorded spectral responses with change in concentration of Cu(II) ions, the binding ratio of α-NBT:Cu(II) complexation is calculated as 2:1 with the limit of detection of Cu(II) ions as 3.12 µM and binding constant for ligand–metal interaction equal to 0.15 x 105 M−1.

A novel naphthalimide-appended salamo-type fluorescent sensor for continuous “on-off-on” detection of Cu2+ and CN− ions, sensing mechanisms and applications

A novel naphthalimide-appended salamo-type fluorescence sensor (E)-2-hydroxy-3-methoxybenzaldehyde O-(2-((((E)-1-(3-(1,3-dioxo-1H-benzo[de]isoquinolin-2(3H)-yl)-2-hydroxyphenyl)ethylidene)amino)oxy)ethyl) oxime (H2L) for continuous identification of copper(II) and cyanide ions was constructed. The sensor H2L exhibited relatively high selectivity for Cu2+ in a 1:1 stoichiometric manner, and the increase of Cu2+ led to quenching of blue fluorescence, with a minimum detection limit of 9.37 × 10−9 M. In addition, the complex generated by the sensor H2L with Cu2+ could in situ recognize CN−, the L-Cu2+ complex coordinates with CN− in a 1:1 stoichiometric manner and exhibits high selectivity, and the addition of CN− results in enhanced blue fluorescence. The time response and pH effect tests demonstrated the advantages of H2L such as fast response for the continuum recognition of Cu2+ with CN− and wide pH test range. Based on the above results, an attempt was made to determine Cu2+ with CN− in spiked environmental water samples with good recoveries.

Controllable functionalization of amino-functionalized graphene quantum dots as fluorescent probe for detection of Cu(Ⅱ) ions detection

Herein, the amino-functionalized graphene quantum dots (GQDs) can be applied for selective detection of Cu(Ⅱ) ions in solutions via photoluminescence (PL) measurement, the PL emission intensities of the GQDs gradually decreased with the increase of Cu2+ concentration (0–100 μm), the PL intensity (quenching effect) decreases almost linearly with increasing Cu2+ concentration. Its correlation coefficient R2 is 0.9529. Quenching of the PL emission by the presence of copper(Ⅱ) ions is attributed to the surface functional groups attached to the GQDs, which can interact with metal ions so that the electrons in the excited state of the GQDs are transferred into the unoccupied orbits of Cu(Ⅱ) ions. Corresponding physical mechanism is proposed to gain an understanding about how the presence of the Copper(Ⅱ) ions can affect the PL emission from GQDs.

Synergistic optical sensing: Selective colorimetric analysis of copper in environmental and biological samples

A groundbreaking optical sensing membrane has been engineered for the accurate assessment of copper ions. The pliable poly(vinyl chloride) membrane is formulated through the integration of sodium tetraphenylborate (Na-TPB), 4-(2-hydroxy-4-nitro azobenzene)-2-methyl-quinoline (HNAMQ), and tri-n-octyl phosphine oxide (TOPO), in conjunction with o-nitrophenyl octyl ether (o-NPOE). The sensor membrane undergoes a thorough investigation of its composition to optimize performance, revealing that HNAMQ serves a dual role as both an ionophore and a chromoionophore. Simultaneously, TOPO contributes to enhancing the complexation of HNAMQ with copper ions. Demonstrating a linear range for Cu2+ ions spanning from 5.0 × 10−9 to 7.5 × 10−6 M, the proposed sensor membrane showcases detection and quantification limits of 1.5 × 10−9 and 5.0 × 10−9 M, respectively. Rigorous assessments of potential interferences from other cations and anions revealed no observable disruptions in the detection of Cu2+. With no discernible HNAMQ leaching, the membrane demonstrates rapid response times and excellent durability. The sensor exhibits remarkable selectivity for Cu2+ ions and can be regenerated through exposure to 0.05 M EDTA. Successful application of the sensor in determining the presence of Cu2+ in biological (blood, liver and meat), soil, food (coffee, black tea, sour cherry juice, black currant, and milk powder) and environmental water samples underscores its efficacy.

Efficient recovery of copper resources from copper smelting waste acid based on Cu(Ⅱ)/As(Ⅲ) competitive sulfuration mechanism

Currently, domestic and foreign copper smelting waste acid mainly employ sulfuration method to realize the separation of Cu(Ⅱ) and As(Ⅲ), facing the problem of unreasonable sulfidizing agent dosage and sulfidation time. If excessive sulfidizing agent dosage or overly long sulfidation time, it will lead to human health threat and large hazardous waste volume. If insufficient sulfidizing agent dosage or overly short sulfidation time, it will cause the waste of copper resources and substandard treatment solution.In this paper, the competitive sulfuration mechanism of Cu(Ⅱ)/As(Ⅲ) solution (C(As(Ⅲ)) = 10 g/L) with different Cu(Ⅱ) concentrations is revealed, i.e., when C(Cu(Ⅱ))≥7 g/L, the sulfidation sequence of Cu(Ⅱ) and As(Ⅲ) follows the solubility product constant (Ksp); when C(Cu(Ⅱ))≤6 g/L, the precipitation process of Cu(Ⅱ)/As(Ⅲ) is dominated by the liquid-phase mass-transfer mechanism (ion diffusion). The sulfide precipitation of Cu(Ⅱ)/As(Ⅲ) is a co-deposition process. With the increase of sulfidizing agent dosage (S/Cu ratio) and sulfidation time (t), the Cu(Ⅱ) concentration gradually decreases to reach complete removal, while the further increase of S/Cu ratio and t leads to the decrease of copper content in the sulfide precipitates. Finally, the methods are demonstrated that detected accurately Cu(Ⅱ) and As(Ⅲ) concentrations in a rapid and non-destructive manner. This work not only provides a novel perspective on the efficient separation of Cu(Ⅱ)/As(Ⅲ) in copper smelting waste acid, but also opens a unique approach for direct and rapid detection of Cu(Ⅱ)/As(Ⅲ) concentration during the sulfuration process. Hence, this research is a guide for the regulating means (S/Cu and t) in the actual multi-step sulfuration process of copper smelting waste acid treatment and electrorefining solution purification.

Electrochemical detection of heavy metal ions in water using MWCNT/ZnO nanocomposite

A nanocomposite of multi-walled carbon nanotubes (MWCNTs) decorated with zinc oxide nanoparticles (ZnO NPs) was fabricated via an in-situ hydrothermal approach and implemented as a modified electrode for stripping voltammetric detection of dissolved heavy metal ions. The MWCNT/ZnO exhibited a high specific surface area of 53 m2/g and charge transfer conductivity amplified to 26 S/cm. By square wave voltammetry, the nanocomposite sensor achieved wide linear detection of Cu(II) from 1 to 800 ppb, Pb(II) from 5 to 1000 ppb, and Hg(II) from 1 to 900 ppb, along with low limits of detection reaching 0.8, 1.2, and 0.7 ppb, respectively. The 3–5X enhanced sensitivity versus an unmodified screen-printed carbon electrode confirms performance gains supplied by the tailored hybrid interface. Selectivity testing produced distinct, well-resolved oxidation peaks for each metal ion target that remained unaffected by high off-target concentrations of Mn(II), Co(II), and Fe(III) interferents. Accurate spike recoveries between 95% and 102% were obtained from quantifying ternary mixtures across various Cu(II):Pb(II):Hg(II) compositions, substantiating the capability for simultaneous multianalyte analysis. The simple preparation, high sensitivity and selectivity, and accuracy for direct water testing validates the nanocomposite as a practical portable sensor for on-site toxic heavy metal detection.

Synthesis and Properties of a Triphenylamine‐Based Fluorescent Probe for the Continuous Detection of Cu2+ and EDTA

AbstractA fluorescent probe NS was successfully developed using triphenylamine aldehyde and 1‐hydroxy‐2‐naphthaldehyde. NS demonstrated selective recognition of Cu2+ in a DMSO/H2O solution, forming a stable 1 : 1 complex that led to fluorescence quenching. The addition of EDTA resulted in fluorescence recovery. The fluorescent intensity of NS showed a linear correlation with Cu2+ concentration within the range of 2~14 μmol ⋅ L−1, with a detection limit of 39 nmol ⋅ L−1 and a binding constant of 1.56×103 L mol−1. Additionally, the detection limit of the NS‐Cu2+ complex for EDTA was calculated to be 187 nmol ⋅ L−1. NS also displayed promising applications in the environmental and alcoholic drinks for detecting Cu2+ in water, wine, and Chinese Baijiu samples.

A Coumarin-Based Fluorescent Probe for Selective Detection of Cu(II) and Imaging in Human Cell

A Coumarin-Based Fluorescent Probe for Selective Detection of Cu(II) and Imaging in Human Cell

Effective Detection of Cu(II) Ions Based on Carbon Dots@Exfoliated Layered Double Hydroxides Composites Fluorescence Probe.

A series of carbon dots@exfoliated layered double hydroxides (CDs@LDH) composites were hydrothermally fabricated by Mg/Al LDH and formamide. The results of FTIR, UV-vis, and XPS spectra in company with HRTEM images showed that crystalline nano CDs formed on the single layer of LDH by Mg-C bond. With the increase of solvothermal reaction time from 2 to 6h, the band gap and the binding energy of aminic and graphitic N species of CDs@LDH composites decreased, whereas the crystallinity increased. The fluorescence peaks of CDs@LDH composites could be deconvoluted into short-wavelength (416nm) and large-wavelength (443nm) components by Gaussian function, and the fluorescence intensities of both components enhanced with the extension of the solvothermal reaction time. The simultaneous enhancements of fluorescence lifetime and quantum yield resulted from the relatively high electron density in graphitic nitrogen of CDs@LDH, whereas the reduction of nonradiative rate was due to the high crystallinity in the carbon core of CDs@LDH. A strong exciton-lattice interaction also has been validated based on the excitation and emission spectra of CDs@LDH, so the fluorescence emission of CDs@LDH composite was heavily related to its crystalline carbon core and nitrogen-containing groups. CDs@LDH with high nitrogen-containing exhibited a superior detection property for Cu2+ ion sensing with the linear range of 26.90 ~ 192.20μM and a limit of detection of 0.1957μM. The photo-induced electron transfer (PET) process dominated the fluorescence quenching of CDs@LDH by Cu2+ ion since the fluorescence lifetime decreased with the increase of Cu2+ ion concentration.

Synthesis of Coumarinylhydrazone Fluorescent Probe and its Relay Recognition of Cu2+ and HPO42.

A novel coumarinylhydrazone fluorescent probe L was designed and synthesized from 4-(diethylamino)salicylaldehyde, its structure was characterized by NMR, IR. Fluorescence emission spectra showed that in ethanol solution, probe L could form a 1:1 complex L-Cu2+ with Cu2+ to realize the "turn-off" detection of Cu2+ with high specificity and sensitivity (3.7 × 10-7mol/L). Meanwhile, the complex L-Cu2+ had a specific fluorescence-enhanced response to HPO42- with a detection limits down to 5.6 × 10-7mol/L and was resistant to the effects of many common anions (NO2-, N3-, CO32-, SO32-, HPO42-, I-, Br-, F-, HCO3-, SO42-, NO3-, Cl-, CH3COO-, Cr2O72-, S2O32-, P2O74-). Detection mechanism could be HPO42- captured Cu2+ of the complex and released the free ligand L. At last, the complex L-Cu2+ was successfully applied to the determination of HPO42- in different environmental water samples, and the spiked recoveries ranged from 98.05% to 108.18% and the relative standard deviations of 0.75% ~ 2.9%, which had good application prospects.

Fabrication of Paper-Based Silver Nanoparticle (AgNP) Sensors for Smartphone-Based Colorimetric Detection of Cu (II) in Water

Detection of heavy metals in water has long been a key area of study due to the adverse health effects these substances may bring. Multiple methods of detecting heavy metals have already been established. Though these methods are highly selective and can detect heavy metals in trace amounts, they commonly require specialized equipment. Thus, producing an inexpensive, reliable, and convenient sensor that could be used for point-of-need applications is of great interest. This study focuses on fabricating paper-based silver nanoparticle (AgNP) sensors for the smartphone-based colorimetric detection of Cu2+ ions in water. Polymer-decorated AgNPs functionalized by chitosan, glutaraldehyde, and polyethyleneimine were used as the main sensing mechanism for the paper-based sensors. Various fabrication methods were tested, and the optimal fabrication method was through the rectangular soak method with a total of 5 coatings as it produced the most uniform sensors. The calibration curve was studied over concentrations from 0.5 mM to 50 mM of Cu2+ across multiple parameters. It was found that there was a linear correlation between the Euclidean distance measured in reference to the blank filter paper against the concentration of copper in the analyte. The calibration curve exhibited a dynamic linear range between 2 mM to 28 mM of Cu2+ with R2 = 0.99789. The LOD and LOQ were reported at 94.9438 ppm and 316.4793 ppm, respectively. Lastly, selectivity studies were also performed to determine the sensor’s response to other metal ions. It was found that the response of the sensor to Cu2+ was significantly different from those elicited by Ni2+, Cd+, Mn2+, Ca2+, Mg2+, Sn2+, K+, Cr3+, Al3+, Ba2+, Na+, Zn2+, Fe3+, and Fe2+. The study demonstrated its strong potential as rapid on-site detection method for Cu (II) in industrial wastewater.

Gadolinium-Doped Carbon Dots with Dual Enzyme Activity for Visual Detection of Cu2+ and Antibacterial Applications

Gadolinium-Doped Carbon Dots with Dual Enzyme Activity for Visual Detection of Cu²⁺ and Antibacterial Applications

Fluorescent Polymeric Sensor for Selective and Sensitive Detection of Cu(II) ions in Aqueous Medium

In our study, a selective and sensitive determination method was developed for Cu(II) ions by spectrofluorimetry. For this purpose, a polymeric membrane was prepared to determine Cu(II) ions by curing crosslinkers, functional monomers, and photoinitiators under UV light. The membrane was characterized, and the optimum conditions for determining Cu(II) ions were systematically investigated. The detection was performed at pH 5.0 in as little as 20 seconds at excitation and emission wavelengths of 376 nm and 455 nm, respectively. The linear range was 7.86.10-9-1.57.10-7 mol/L, and the method's detection limit was 2.24.10-9 mol/L. In addition, the sensor's repeatability, stability, and life were examined, and recovery studies were conducted. As a result, the developed method has been successfully applied to wastewater samples as a real sample. In addition, determining Cu(II) ions at low concentrations can be done quickly, reliably, and with high selectivity and sensitivity.

Super stable and water-dispersible CsPbBr3 perovskite quantum dots for the efficient detection of Cu (II) and glutathione

Perovskite quantum dots (PQDs) have made substantial advances in solar cells, light-emitting diodes, and photocatalysis due to their distinctive optical and electrical properties. The intrinsic instability of PQDs restricts their practical applications, which makes using them in the food sector difficult. The present work indicates that the long-term stability of ionic crystals by using the two-ligand mechanism of 4-bromo-butyric acid (BBA) and oleylamine (OLA) can provide prospects for the use of PQDs in the food industry. The results reveal that monodispersed CsPbBr3@BBA QDs, obtained in water, exhibit high photoluminescence quantum yields (PLQYs). Notably, the photoluminescence characteristics of CsPbBr3@BBA QDs remained remarkably stable even after dispersing the materials in an aqueous solution for 140 h, indicating the robust structural stability of CsPbBr3@BBA QDs. We used the CsPbBr3@BBA QDs to selectively detect the presence of Cu2+ in food samples such as ordinary fruits and tea. The results exhibited a good linearity within the range of 0 to 80 μM, with the limit of detection of 0.8 μM. At the same time, this sensor proposed here possessed a linear range of 0 to 250 μM and a limit of detection of 2.84 μM for glutathione (GSH) detection. Furthermore, it is shown that the QDs-Cu2+ fluorescent probe also displayed selective fluorescence recovery after exposure to GSH. The low cost and ease of preparation of this sensor offer enormous industrialization potential and opportunity, thereby accelerating the development of the sensor in the field of food safety.

A dual-emission ratiometric luminescence probe based on Zr-MOFs for the efficient detection of Cu2+ in aqueous solutions

A novel dual-emission ratio luminescent probe (Eu(DPA)3@UIO-66-NH2) for the detection of Cu[Formula: see text] in an aqueous solution was successfully prepared by linking the Zr-MOFs material UIO-66-NH2 with the lanthanide complex Na3[Eu(DPA)3] through the interaction between functional groups. The synthesized Eu(DPA)3@UIO-66-NH2 inherits the advantages of MOFs and lanthanide complexes, and it not only has excellent luminescence performance but also shows good dispersion and structural stability in aqueous solution. The characteristics of dual-emission light can achieve specific ratiometric luminescence detection of Cu[Formula: see text]. In addition, the probe exhibited high sensitivity for the detection of Cu[Formula: see text]with a detection limit as low as 0.89 [Formula: see text]M. It can provide an efficient and stable platform for the convenient and rapid detection of Cu[Formula: see text] in aqueous solutions and has the potential for development applications.

Molecularly imprinted polymer on cotton materials as substrates for smartphone-based image and distance-based analysis of Cu(II) in water samples.

Cotton fabric was used as a substrate for smartphone-based image analysis of Cu(II) in drinking water. To enhance its selective and specific binding sites on the cotton surface, a molecularly imprinted polymer (MIP) was introduced using color complexes of 4-(2-pyridylazo)resorcinol-Cu(II) (PAR-Cu(II)) as the template molecule, 3-aminopropyltriethoxysilane (APTES) as the functional monomer, tetraethoxysilane (TEOS) as the crosslinker and NH3 as the catalyst. After achieving optimum conditions, the obtained CF-MIP/PAR-Cu(II) presented a red color, which was changed to yellow upon the removal of Cu(II) with 1.5 M HCl. After using CF-MIP/PAR to detect Cu(II), the red, green and blue intensities of the images captured using a smartphone were analyzed using the ImageJ program. For the calibration curve plotted between Δgreen intensity and Cu concentration, the linear range was 0.10-1.0 mg L-1 with the best correlation coefficient (R2) of 0.999. The limit of detection (LOD) and the limit of quantification (LOQ) were found to be 0.038 and 0.11 mg L-1, respectively. To obtain a distance-based device, MIP-modified cotton thread (CT-MIP/PAR) with a four-channel design was used as an alternative device. The distance of red color development was measured after using CT-MIP/PAR to detect Cu(II). The linear range was 0.50-3.0 mg L-1 with an R2 of 0.997. The LOD and LOQ were 0.18 and 0.56 mg L-1, respectively. The proposed methods provide simple, portable and inexpensive devices with high accuracy and precision for the detection of Cu(II) in drinking water.