A new strategy for utilization of gasification ash: Manganese oxides-modified activated carbon for efficient copper citrate removal.

To address the challenges posed by solid waste generated from coal gasification ash, a pyrolysis self-activation method was employed to prepare activated carbon by gasification ash, followed by the modification with manganese oxide to enhance its adsorption performance. Subsequently, the removal efficiency and mechanism for copper citrate were investigated. The results demonstrated the successful preparation of manganese oxides modified gasification ash-derived activated carbon (GAC-MnOx), exhibiting a specific surface area of 158.3 m2/g and a pore volume of 0.1948 cm³/g. The kinetic process could be described by the pseudo-second-order kinetic model (R2 = 0.958). High removal efficiency and low concentration of dissolved Mn were observed within the pH range of 3-10, where the adsorption capacity of GAC-MnOx for copper citrate exhibited an inverse relationship with pH. Notably, the fitting results of the Langmuir model demonstrated that the maximum adsorption capacity of GAC-MnOx for copper citrate is determined to be 7.196 mg/g at pH 3. The adsorption capacity of GAC-MnOx was found to be significantly reduced to 0.26 mg/g as the pH decreased below 2, potentially attributed to the dissolution of Mn. The findings of the Dual-Mode model demonstrated that the copper citrate removal mechanism by GAC-MnOx involved both surface adsorption and precipitation processes as follows: the porous structure of activated carbon enables physical adsorption of copper citrate, the MnOx or oxygen-containing functional groups establish chemical bonds with copper citrate and subsequently precipitate onto the surface of the adsorbent. The physical adsorption remains predominant in the removal of copper citrate, despite a gradual decrease in its proportion with increasing pH and equilibrium concentrations. Moreover, the X-ray photoelectron spectroscopy results indicated that copper citrate might be oxidized by MnOx to release copper ions and be retained on the surface of the adsorbent, meaning the adsorption efficiency of Cu(II)-Cit by GAC was enhanced through MnOx oxidation. This study could provide a new strategy for the high-value resource utilization of gasification ash.

Association between Copper Exposure and Cognitive Function: A Cross-Sectional Study in a County, Guangxi, China.

There has been growing attention to the impact of copper exposure on cognitive function; however, current research on the specific information regarding urinary copper and cognitive function is limited, particularly detailed analyses in the Chinese adult population. This study aimed to explore the association between copper exposure and cognitive function in a cross-sectional design. A total of 2617 participants in a county, Guangxi Zhuang Autonomous Region (Guangxi), China, were included. The mini-mental state examination (MMSE) was used to assess cognitive function, and inductively coupled plasma mass spectrometry was used to measure urinary metal levels. Spearman's rank correlation was used to analyze the correlation between urinary copper levels and various cognitive function assessment indices. After adjusting for potential confounders, binary logistic regression was used to explore the association between urinary copper levels and the risk of cognitive impairment (CI) as revealed by MMSE, and restricted cubic spline regression was further used to explore the dose-response relationship. The results showed a negative correlation between urinary copper levels and orientation, attention and calculation, memory, language ability, and MMSE total scores (P < 0.05). Compared with the low copper exposure group, the high exposure group showed a 58.5% increased risk of CI (OR = 1.585, 95%CI: 1.125 to 2.235, P = 0.008). A significant linear dose-response relationship was observed between urinary copper levels and the risk of CI (P overall = 0.045, P nonlinearity = 0.081). Our findings suggest that higher copper exposure may be associated with CI in the population of a county, Guangxi, China.

Interfacial Hydrogen-Bond Interactions Driven Assembly toward Polychromatic Copper Nanoclusters.

Constructing versatile metal nanoclusters (NCs) assemblies through noncovalent weak interactions between inter-ligands is a long-standing challenge in interfacial chemistry, while compelling interfacial hydrogen-bond-driven metal NCs assemblies remain unexplored so far. Here, the study reports an amination-ligand o-phenylenediamine-coordinated copper NCs (CuNCs), demonstrating the impact of interfacial hydrogen-bonds (IHBs) motifs on the luminescent behaviors of metal NCs as the alteration of protic solvent. Experimental results supported by theoretical calculation unveil that the flexibility of interfacial ligand and the distance of cuprophilic CuI···CuI interaction between intra-/inter-NCs can be tailored by manipulating the cooperation between the diverse IHBs motifs reconstruction, therewith the IHBs-modulated fundamental structure-property relationships are established. Importantly, by utilizing the IHBs-mediated optical polychromatism of aminated CuNCs, portable visualization of humidity sensing test-strips with fast response is successfully manufactured. This work not only provides further insights into exploring the interfacial chemistry of NCs based on inter-ligands hydrogen-bond interactions, but also offers a new opportunity to expand the practical application for optical sensing of metal NCs.

Potential effects of Cu2+ stress on nitrogen removal performance, microbial characteristics, and metabolism pathways of biofilm reactor.

Sequencing batch biofilm reactors (SBBR) were utilized to investigate the impact of Cu2+ on nitrogen (N) removal and microbial characteristics. The result indicated that the low concentration of Cu2+ (0.5 mg L-1) facilitated the removal of ammonia nitrogen (NH4+-N), total nitrogen (TN), nitrate nitrogen (NO3--N), and chemical oxygen demand (COD). In comparison to the average effluent concentration of the control group, the average effluent concentrations of NH4+-N, NO3--N, COD, and TN were found to decrease by 40.53%, 17.02%, 10.73%, and 15.86%, respectively. Conversely, the high concentration of Cu2+ (5 mg L-1) resulted in an increase of 94.27%, 55.47%, 22.22%, and 14.23% in the aforementioned parameters, compared to the control group. Low concentrations of Cu2+ increased the abundance of nitrifying bacteria (Rhodanobacter, unclassified-o-Sacharimonadales), denitrifying bacteria (Thermomonas, Comamonas), denitrification-associated genes (hao, nosZ, norC, nffA, nirB, nick, and nifD), and heavy-metal-resistant genes related to Cu2+ (pcoB, cutM, cutC, pcoA, copZ) to promote nitrification and denitrification. Conversely, high concentration Cu2+ hindered the interspecies relationship among denitrifying bacteria genera, nitrifying bacteria genera, and other genera, reducing denitrification and nitrification efficiency. Cu2+ involved in the N and tricarboxylic acid (TCA) cycles, as evidenced by changes in the abundance of key enzymes, such as (EC:1.7.99.1), (EC:1.7.2.4), and (EC:1.1.1.42), which initially increased and then decreased with varying concentrations of Cu2+. Conversely, the abundance of EC1.7.2.1, associated with the accumulation of nitrite nitrogen (NO2--N), gradually declined. These findings provided insights into the impact of Cu2+ on biological N removal.

Cu Based Dilute Alloys for Tuning the C2+ Selectivity of Electrochemical CO2 Reduction.

Electrochemical CO2 reduction is a promising technology for replacing fossil fuel feedstocks in the chemical industry but further improvements in catalyst selectivity need to be made. So far, only copper-based catalysts have shown efficient conversion of CO2 into the desired multi-carbon (C2+) products. This work explores Cu-based dilute alloys to systematically tune the energy landscape of CO2 electrolysis toward C2+ products. Selection of the dilute alloy components is guided by grand canonical density functional theory simulations using the calculated binding energies of the reaction intermediates CO*, CHO*, and OCCO* dimer as descriptors for the selectivity toward C2+ products. A physical vapor deposition catalyst testing platform is employed to isolate the effect of alloy composition on the C2+/C1 product branching ratio without interference from catalyst morphology or catalyst integration. Six dilute alloy catalysts are prepared and tested with respect to their C2+/C1 product ratio using different electrolyzer environments including selected tests in a 100-cm2 electrolyzer. Consistent with theory, CuAl, CuB, CuGa and especially CuSc show increased selectivity toward C2+ products by making CO dimerization energetically more favorable on the dominant Cu facets, demonstrating the power of using the dilute alloy approach to tune the selectivity of CO2 electrolysis.

High-Performance Pomegranate-Like CuF2 Cathode Derived from Spent Lithium-Ion Batteries.

With the large-scale application of lithium-ion batteries (LIBs), a huge amount of spent LIBs will be generated each year and how to realize their recycling and reuse in a clean and effective way poses a challenge to the society. In this work, using the electrolyte of spent LIBs as solvent, we in-situ fluorinate the conductive three-dimensional porous copper foam by a facile solvent-thermal method and then coating it with a cross-linked sodium alginate (SA) layer. Benefiting from the solid-electrolyte interphase (SEI) that accommodating the volume change of internal CuF2 core and SA layer that inhibiting the dissolution of CuF2, the synthesized CuF2@void@SEI@SA cathode with a pomegranate-like structure (yolk-shell) exhibits a large reversible capacity of ~535 mAh g-1 at 0.05 A g-1 and superb cycling stability. This work conforms to the development concept of green environmental protection and comprehensively realizes the unity of environmental, social and economic benefits.

Copper-Graphene Composite (CGC) Conductors: Synthesis, Microstructure, and Electrical Performance.

Improving the electrical performance of copper, the most widely used electrical conductor in the world is of vital importance to the progress of key technologies, including electric vehicles, portable devices, renewable energy, and power grids. Copper-graphene composite (CGC) stands out as the most promising candidate for high-performance electrical conductor applications. This can be attributed to the superior properties of graphene fillers embedded in CGC, including excellent electrical and thermal conductivity, corrosion resistance, and high mechanical strength. This review highlights the recent progress of CGC conductors, including their fabrication processes, electrical performances, mechanisms of copper-graphene interplay, and potential applications.

Colloidal Synthesis of Cu3N Nanorods and Construction of Cu3N-Cu2O Heteronanostructures via Epitaxial Growth.

The synthesis of transition metal nitrides nanocrystals (TMNs NCs) has posed a significant challenge due to the limited reactivity of nitrogen sources at lower temperatures and the scarcity of available synthesis methods. In this study, we present a novel colloidal synthesis strategy for the fabrication of Cu3N nanorods (NRs). It is found that the trace oxygen (O2) plays an important role in the synthesis process. And a new mechanism for the formation of Cu3N is proposed. Subsequently, by employing secondary lateral epitaxial growth, the Cu3N-Cu2O heteronanostructures (HNs) can be prepared. The Cu3N NRs and Cu3N-Cu2O HNs were evaluated as precursor electrocatalysts for the CO2 reduction reaction (CO2RR). The Cu3N-Cu2O HNs demonstrate remarkable selectivity and stability with ethylene (C2H4) Faradaic efficiency (FE) up to 55.3%, surpassing that of Cu3N NRs. This study provides innovative insights into the reaction mechanism of colloidal synthesis of TMNs NCs and presents alternative options for designing cost-effective electrocatalysts to achieve carbon neutrality.

Photoinduced Ordered Growth of Copper-Doped Polyaniline Nanotubes: A Method to Improve the Catalytic Activity for C-N Coupling Reactions.

Polyaniline-supported metal nanoparticles (M@PANIs) have been widely employed as catalysts for organic reactions. Traditionally, the catalytic activities of the materials can be improved by introducing functional groups onto the aniline monomers, but it may enhance the catalyst cost and reduce the production yield of the material. This work reports a new strategy for improving the catalytic activity of M@PANIs. It was found that induced by visible light in the presence of a polymeric carbon nitride catalyst and copper dopant, the oxidative polymerization of simple aniline occurred slowly and orderly to produce the copper-doped polyaniline nanotubes. The unique tubular structure protected the catalytically active Cu(I) inside and endowed even more sufficient contact of the catalytic sites with reactants so that the material exhibited excellent catalytic performances in C-N coupling reactions.

Construction of the fluorescence sensing platform with a bifunctional Cu@MOF nanozyme for determination of alkaline phosphatase and its inhibitor.

In this work, a novel and sensitive fluorescence sensing system for alkaline phosphatase (ALP) was constructed using a bifunctional copper metal-organic framework (Cu@MOF) nanozyme, which had excellent oxidase-mimetic activity and fluorescence properties. Owing to the presence of 2-amino-1,4-benzenedicarboxylic acid (1,4-BDC-NH2) ligand, Cu@MOF displays excellent fluorescence performance at 444 nm. Additionally, Cu2+ endows the oxidase-like activity of Cu@MOF, which could trigger p-phenylenediamine (PPD) to be oxidized to a brown product (PPDox) and quench the photoluminescence of Cu@MOF through the inner filtration effect (IFE). As the preferential affinity of ATP for Cu2+, the catalytic activity of Cu@MOF was significantly reduced once ATP was added, thus PPD could not be oxidized and fluorescence was recovered. In the presence of ALP, ATP was hydrolyzed to adenosine and Pi, which allowed Cu@MOF to regain its catalytic activity and continued to catalyze the generation of PPDox. The fluorescence of Cu@MOF was therefore weakened once again. The ALP activity was directly proportional to the degree of decrease in fluorescence intensity. Thus, this novel fluorescence sensing strategy had a linear range of 0.5-60 U/L and the limit of detection was 0.14 U/L. The established sensing method could also be used to for ALP inhibitors screening, and achieved satisfactory results in determining the level of ALP activity in human serum.

S-Allyl-L-cysteine (SAC) inhibits copper-induced apoptosis and cuproptosis to alleviate cardiomyocyte injury.

Cardiomyocyte injury is closely related to various myocardial diseases, and S-Allyl-L-cysteine (SAC) has been found to have myocardial protective effects, but its mechanism is currently unclear. Meanwhile, copper also has various physiological functions, and this study found that copper inhibited cell viability in a concentration and time-dependent manner, and was associated with multiple modes of death. Elesclomol plus CuCl2 (ES + Cu) significantly inhibited cell viability, and this effect could only be blocked by copper chelator TTM, indicating that "ES + Cu" induced cuproptosis in cardiomyocytes. SAC reduced the inhibitory effects of high concentration copper and "ES + Cu" on cell viability in a concentration and time-dependent manner, indicating that SAC plays a cardioprotective role under stress. Further mechanism study showed that high concentration of copper significantly induced cardiomyocyte apoptosis and increased the levels of LDH, MDA and ROS, while SAC inhibited the apoptosis and injury of cardiomyocytes induced by copper. "ES + Cu" significantly increased intracellular copper levels and decreased the expression of FDX1, LIAS, Lip-DLST and Lip-DLAT; FDX1 siRNA did not affect the expression of LIAS, but further reduced the expression of Lip-DLST and Lip-DLAT; SAC did not affect the expression of these genes, but enhanced the effect of "ES + Cu" in down-regulating these gene expression and restored intracellular copper levels. In addition, "ES + Cu" reduced ATP production, weakened the activity of mitochondrial complex I and III, inhibited cell viability, and increased the contents of injury markers LDH, MDA, CK-MB and cTnI, while SAC significantly improved mitochondrial function injury and cardiomyocyte injury induced by "ES + Cu". Therefore, SAC can inhibit apoptosis and cuproptosis to play a cardioprotective role.

Regulation and microbial response mechanism of nitric oxide to copper-containing swine wastewater treated by Pistia stratiotes.

As a signaling molecule, Nitric oxide (NO) has been widely used in abiotic stress mitigation studies.Pistia stratiotes showed a good synergistic removal effect on heavy metals, nitrogen and phosphorus, but the high concentration of copper(Cu) in swine wastewater inhibited the comprehensive removal ability of Pistia stratiotes. At present, it is not clear how the addition of NO regulates the stress resistance mechanism of Pistia stratiotes to copper in swine wastewater, and the microbial response mechanism accompanying this process is not yet clear. Therefore, in the concentration range of 0.31∼4 mg·L-1Cu2+ and NO concentration of 0,0.05 and 0.1 mg·L-1, the removal effect of Pistia stratiotes on copper from swine wastewater was studied. The results showed as follows: The treatment of non-available copper in groups M and H increased by 10.67% and 22.31%, respectively, compared with that in group L. The critical point of inhibiting effect of NO on growth rate was 2.03 mg·L-1Cu. By measuring three-dimensional fluorescence spectrum, combined with parallel factor analysis and principal component analysis, it was confirmed that exogenous addition of NO affected the humification degree of dissolved organic matter(DOM) and promoted the chelation of organic matter with copper. With the increase of Cu concentration, the Reyranella and Prosthecobacter with certain copper resistance gradually gained advantages. Redundancy analysis(RDA) showed that Emiticicia had a strong correlation with the removal rates of ammonia nitrogen, total phosphorus and copper in pig farm wastewater, while hgcI_clade had a strong correlation with the removal rates of total nitrogen. In conclusion, controlling the dosage of NO can effectively improve the tolerance and removal effect of Pistia stratiotes on copper in swine wastewater, which is of great significance for promoting the treatment and resource transformation of swine wastewater.

Hole-Carrier-Dominant Transport in 2D Single-Crystal Copper.

In 2D noble metals like copper, the carrier scattering at grain boundaries has obscured the intrinsic nature of electronic transport. However, it is demonstrated that the intrinsic nature of transport by hole carriers in 2D copper can be revealed by growing thin films without grain boundaries. As even a slight deviation from the twin boundary is perceived as grain boundaries by electrons, it is only through the thorough elimination of grain boundaries that the hidden hole-like attribute of 2D single-crystal copper can be unmasked. Two types of Fermi surfaces, a large hexagonal Fermi surface centered at the zone center and the triangular Fermi surface around the zone corner, tightly matching to the calculated Fermi surface topology, confirmed by angle-resolved photoemission spectroscopy (ARPES) measurements and vivid nonlinear Hall effects of the 2D single-crystal copper account for the presence of hole carriers experimentally. This breakthrough suggests the potential to manipulate the majority carrier polarity in metals by means of grain boundary engineering in a 2D geometry.

Enantioselective Copper-Catalyzed Sequential Hydrosilylation of Arylmethylenecyclopropanes.

Despite impressive advances in the construction of enantioenriched silacarbocycles featuring silicon-stereogenic centers via a selection of well-defined sila-synthons, the development of a more convenient and economic method with readily available starting materials is significantly less explored and remains a considerable challenge. Herein, we report the first example of copper-catalyzed sequential hydrosilylation of readily accessible methylenecyclopropanes (MCPs) and primary silanes, affording an efficient and convenient route to a wide range of chiral silacyclopentanes bearing consecutive silicon- and carbon-stereogenic centers with excellent enantio- and diastereoselectivities (generally ≥98% ee, > 25:1 dr). Mechanistic studies reveal that these reactions combine copper-catalyzed intermolecular ring-opening hydrosilylation of aryl MCPs and intramolecular asymmetric hydrosilylation of the resultant Z/E mixture of homoallylic silanes.

Enhancing Performance and Stability of p-i-n Perovskite Solar Cells with Ag-Cu Codeposited Alloy Electrodes.

In the development of back electrodes for perovskite solar cells (PSCs), the major challenges are stability and cost. To address this, we present an innovative approach: Simultaneous evaporation of two independently controlled sources of metal materials was performed to achieve a uniform distribution of the alloy electrodes. In this study, Ag-Cu alloys (the molar ratio of Ag/Cu is 7/3) with a high-index crystal face (111) and a work function matching perovskite were prepared using a codeposition technique. These properties mitigate nonradiative carrier recombination at the interface and reduce the energy barrier for carrier migration. Consequently, compared to Ag based PSCs (22.77%), the implementation of Ag-Cu alloy (Ag/Cu is 7/3)-based PSCs resulted in a power conversion efficiency of 23.72%. In a 1500 h tracking test in ambient air, the Ag-Cu alloy (Ag/Cu is 7/3)-based PSCs maintained their initial efficiency of 86%. This can be attributed to almost no migration of elements from the Ag-Cu alloy electrode to the perovskite layer. Our work presents a vital strategy for improving the stability of PSCs and reducing the costs associated with the back electrode in PSCs.

Ligand-Controlled Copper-Catalyzed Halo-Halodifluoromethylation of Alkenes and Alkynes Using Fluorinated Carboxylic Anhydrides.

Polyhalogenated molecules are often found as bioactive compounds in nature and are used as synthetic building blocks. Fluoroalkyl compounds hold promise for the development of novel pharmaceuticals and agrochemicals, as the introduction of fluoroalkyl groups is known to improve lipophilicity, membrane permeability, and metabolic stability. Three-component 1,2-halo-halodifluoromethylation reactions of alkenes are useful for their synthesis. However, general methods enabling the introduction of halodifluoromethyl (CF2X) and halogen (X') groups in the desired combination of X and X' are lacking. To address this gap, for the first time, we report a three-component halo-halodifluoromethylation of alkenes and alkynes using combinations of commercially available fluorinated carboxylic anhydrides ((CF2XCO)2O, X = Cl and Br) and alkali metal halides (X' = Cl and Br). In situ prepared fluorinated diacyl peroxides were identified as important intermediates, and the use of appropriate bipyridyl-based ligands and a copper catalyst was essential for achieving high product selectivity. The synthetic utility of the polyhalogenated products was demonstrated by exploiting differences in the reactivities of their C-X and C-X' bonds to achieve selective derivatization. Finally, the reaction mechanism and ligand effect were investigated using experimental and theoretical methods to provide important insights for the further development of catalytic reactions.

Metabolomic changes in Cryptocaryon irritans from Larimichthys crocea after exposure to copper plate.

Cryptocaryon irritans is a highly detrimental parasite in mariculture, causing significant economic losses to the aquaculture industry of Larimichthys crocea. In recent years, copper and copper alloy materials have been used to kill parasites. In this study, the effect of copper plates on the tomont period of C. irritans was explored. The findings indicated that copper plates effectively eradicated tomonts, resulting in a hatching rate of 0. The metabolomic analysis revealed that a total of 2,663 differentially expressed metabolites (1,032 up-regulated and 1,631 down-regulated) were screened in the positive ion mode, and 2,199 differentially expressed metabolites (840 up-regulated and 1,359 down-regulated) were screened in the negative ion mode. L-arginine and L-aspartic acid could be used as potential biomarkers. Copper plate treatment affected 25 metabolic pathways in the tomont, most notably influencing histidine metabolism, retinol metabolism, the biosynthesis of phenylalanine, tyrosine, and tryptophan, as well as arginine and proline metabolism. It was shown that high concentrations of copper ions caused a certain degree of disruption to the metabolome of tomonts in C. irritans, thereby impacting their metabolic processes. Consequently, this disturbance ultimately leads to the rapid demise of tomonts upon exposure to copper plates. The metabolomic changes observed in this study elucidate the lethal impact of copper on C. irritans tomonts, providing valuable reference data for the prevention and control of C. irritans in aquaculture.

Fluorescence-Based Proteoliposome Methods to Monitor Redox-Active Transition Metal Transmembrane Translocation by Metal Transporters.

Transmembrane transition metal transporter proteins are central gatekeepers in selectively controlling vectorial metal cargo uptake and extrusion across cellular membranes in all living organisms, thus playing key roles in essential and toxic metal homeostasis. Biochemical characterization of transporter-mediated translocation events and transport kinetics of redox-active metals, such as iron and copper, is challenged by the complexity in generating reconstituted systems in which vectorial metal transport can be studied in real time. We present fluorescence-based proteoliposome methods to monitor redox-active metal transmembrane translocation upon reconstitution of purified metal transporters in artificial lipid bilayers. By encapsulating turn-on/-off iron or copper-dependent sensors in the proteoliposome lumen and conducting real-time transport assays using small unilamellar vesicles (SUVs), in which selected purified Fe(II) and Cu(I) transmembrane importer and exporter proteins have been reconstituted, we provide a platform to monitor metal translocation events across lipid bilayers in real time. The strategy is modular and expandable toward the study of different transporter families featuring diverse metal substrate selectivity and promiscuity.

Acetylcholinesterase and butyrylcholinesterase co-immobilized on a copper containing Prussian blue modified electrode for the broad screening of insecticides.

We have developed a bienzymatic biosensor that contains acetylcholinesterase together with butyrylcholinesterase co-immobilized on the same electrode modified with a stabilized copper containing Prussian blue electrodeposited on electrodes coated with 4-aminothiophenol monolayer using diazonium chemistry and copper nanoparticles for improved sensitivity. There are organophosphorus and carbamate neurotoxic insecticides that inhibit only one of the two enzymes, e.g., pirimicarb inhibits butyrylcholinesterase at much lower concentrations than acetylcholinesterase while methomyl inhibits only acetylcholinesterase. Our system is simple and in a single measurement provides a sensitive signal for insecticides' presence based on the inhibition of the enzyme with the highest affinity for each toxic compound. The limits of detection are 50 ng/mL pirimicarb for the bienzymatic biosensor in comparison with 400 ng/mL pirimicarb for the acetylcholinesterase biosensor and 6 ng/mL methomyl for the bienzymatic biosensor, while inhibition is obtained for the butyrylcholinesterase biosensor at 700 ng/mL.

A Terbium Ion-Based Dual-Ligand Fluorescent Probe for Highly Selective and Sensitive Detection of Cu2+ Ions.

In this study, a fluorescent probe (GMP-Tb-SSA) utilizing lanthanide coordination polymer nanoparticles, GMP-Tb, as a sensing platform, and 5-sulfosalicylic acid (SSA) as a cofactor ligand was proposed for the detection of copper ions (Cu2+). GMP-Tb was synthesized by the self-assembly of guanine monophosphate (GMP) and terbium ion (Tb3+), and SSA was introduced as a sensitizer into the GMP-Tb network. Cu2+ could efficiently inhibit the electron transfer from the ligand GMP to the central ion, Tb3+, leading to a significant quench of fluorescence of Tb3+. The method is highly selective with a linear range of 0 to 21 µM and a detection limit of 300 nM. It is not interfered by metal ions, amino acids, and other species, and can be successfully applied to the detection of Cu2+ in real water samples.