Infinite Coordination Polymer Research Articles

1D heteronuclear coordination polymers of hexacyanocobaltate(III) with 2-hydroxymethylpyridine

Three new hexacyanocobaltate(III) complexes, {[M2(hmpy)4Co(µ-CN)4(CN)2]∙2H2O}n (M = Cu(II) (1), Zn(II) (2) and Cd(II) (3)) were synthesized with 2-hydroxymethylpyridine (hmpy) ligand, and characterized by vibration (FT-IR and Raman) spectral, single crystal X-ray diffraction (SC-XRD) and powder X-ray diffraction (PXRD), thermal and elemental analyses techniques. The crystallographic analyses revealed that cyanide complexes 1–3 are infinite one-dimensional coordination polymers. Each M ion is coordinated by two nitrogen and two oxygen atoms from the hmpy ligands and two nitrogen atoms from the cyanide ligands, displaying a distorted octahedral coordination geometry. Similarly, each Co(III) ion is coordinated by six carbon atoms from cyanide ligands to form a distorted octahedral coordination geometry. These complexes form 3D supramolecular networks through OH···O hydrogen bonds and CH···N interactions. Additionally, structural analyses such as metal salts, pH values of the compounds obtained under different conditions were evaluated. A synthesis-structural analyses relation was made from these data.

Lanthanide coordination polymers@CuO nanoparticles: Enhanced self-cascade nanoenzyme activity and ratiometric fluorescence assay of glutathione

Tandem enzyme can catalyze some cascade reactions with high efficiency, and some few tandem enzyme-like mimics have been discovered recently. Further improving the catalytic efficiency of tandem nanoenzymes with facile method may undoubtedly promote and broaden their applications in various fields. In this work, cupric oxide nanoparticles (CuO NPs) with dual-functional enzyme mimics were synthesized using the rapid deposition method in advance, which simultaneously combined with lanthanide infinite coordination polymers (Ln ICPs) during the self-assemble of Tb3+, guanine-5′-triphosphate (GTP) and auxiliary ligand terephthalic acid (TA). Excitingly, the obtained Tb-GTP/TA@CuO ICPs, not only displayed obviously enhanced tandem catalytic activity compared with pure CuO NPs, but also provided a versatile ratiometric platform for ultrahigh selective and sensitive detection of glutathione (GSH) under single-wavelength excitation. A good linear relationship between the ratio signal and the GSH concentration was spanning from 0.001 to 20 μM with an impressive detection limit of 0.50 nM. This study opens a new and universal avenue for preparing integrated multifunctional probes by coupling of nanoenzyme catalytic activity with superior luminescent Ln ICPs through facile method.

Four-component of double-layer infinite coordination polymer nanocomposites for large tumor trimodal therapy via multi high-efficiency synergies

Multimodal /components tumors synergistic therapy is a crucial approach for enhancing comprehensive efficacy. Our research has identified lots of high efficiency synergies among four suitable components, revealing combinations with remarkably low combination index (CI) values (10-3-10-8). These combinations hold promise for large tumor powerful electrothermal-thermodynamic-multi-chemo trimodal therapy. To implement this approach, we developed four-component of double-layer infinite coordination polymer (ICP) nanocomposites, in which hypoxia-activated AQ4N and thermodynamic agent AIPH coordinated with Cu(Ⅱ) to form initial layer of positively charged ICPs-l NPs, chemotherapeutic agents gossypol-hyaluronic acid (G-HA) and CA4 coordinated with Fe(Ⅲ) to form out layer of negatively charged ICPs-2 NPs, then double-layer infinite coordination polymer nanocomposites (ICPs-1@ICPs-2 CNPs) were fabricated by electrostatic adsorption using ICPs-l NPs and ICPs-2 NPs. Cell experiments have extensively optimized the coordination combinations of the four components and the composition of the two layers. A programmable three-stage therapeutic procedure, assisted by a micro-electrothermal needle (MEN), was developed. Under this procedure the resulting nanocomposites demonstrate the powerful trimodal comprehensive therapeutic outcomes for large tumors using lower components dosage, achieving a tumor inhibition rate nearly reaching 100 % and no recurrence for 60 days. This study offers remarkable potential for tumor multimodal /components synergistic therapy in future.

Hyaluronic acid-decorated curcumin-based coordination nanomedicine for enhancing the infected diabetic wound healing

Persistent over-oxidation, inflammation and bacterial infection are the primary reasons for impaired wound repairing in diabetic patients. Therefore, crucial strategies to promote diabetic wound repairing involve suppressing the inflammatory response, inhibiting bacterial growth and decreasing reactive oxygen species (ROS) within the wound. In this work, we develop a multifunctional nanomedicine (HA@Cur/Cu) designed to facilitate the repairing process of diabetic wound. The findings demonstrated that the synthesized infinite coordination polymers (ICPs) was effective in enhancing the bioavailability of curcumin and improving the controlled drug release at the site of inflammation. Furthermore, in vitro and in vivo evaluation validate the capacity of HA@Cur/Cu to inhibit bacterial growth and remove excess ROS and inflammatory mediators, thereby significantly promoting the healing of diabetic wound in mice. These compelling findings strongly demonstrate the enormous promise of this multifunctional nanomedicine for the treatment of diabetic wound.

Intravenous injectable metformin-Cu(II)-EGCG coordination polymer nanoparticles for electrothermally enhanced dual-drug synergistic tumor therapy.

Intravenous injectable metformin-Cu(II)-EGCG infinite coordination polymer nanoparticles (metformin-Cu(II)-EGCG ICP NPs) have been synthesized, and an efficient strategy for synergistic tumor therapy by utilizing these nanoparticles in conjunction with micro-electrothermal needles (MENs) was proposed. These nanoparticles display exceptional uniformity with a diameter of 117.5 ± 53.3 nm, exhibit an extraordinary drug loading capacity of 90% and allow for precise control over the drug ratio within the range of 1 : 1 to 1 : 20 while maintaining excellent thermal stability. Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and X-ray diffraction were employed to determine their chemical structure and coordination state. The combination index (CI) value of the metformin-Cu(II)-EGCG ICP NPs was calculated to be 0.19, surpassing that of the two individual drugs and metformin mixed with EGCG (0.98). Importantly, upon intravenous injection, metformin in nanoparticles demonstrated exceptional stability in the bloodstream, while both drugs were rapidly released within the acidic tumor microenvironment. Animal experiments showcased an impressive tumor inhibition rate of 100% within a mere 20-day time frame after the synergistic therapy with a lower dosage (5.0 mg kg-1 of nanoparticles), coupled with a minimal tumor recurrence rate of only 18.75% over a 60-day observation period. These findings indicate the promising prospects of these nanoparticles in tumor treatment.

Self-Calibrating Lanthanide Infinite Coordination Polymer Constructs Fluorescent Probes: A Sensitive Approach for Early Diagnosis of Hepatocellular Carcinoma and Environmental Analysis.

The development of a self-calibrating ratio fluorescence probe without the need for additional substrates is a major advancement in biosensing. In this study, at room temperature, a self-calibrating infinite coordination polymer (SSA-Tb-ATP ICPs) has been proposed by self-assembling adenosine triphosphate (ATP) with 5-sulfosalicylic acid (SSA) and Tb3+. Due to the antenna effect, SSA-Tb-ATP ICPs exhibited strong green fluorescence emission of Tb3+ (at 547 nm) and blue fluorescence emission of SSA (at 407 nm). This material offers several advantages over existing detection methods, including simplicity of synthesis and exceptional sensitivity. Our self-calibrating SSA-Tb-ATP ICPs demonstrated excellent performance in detecting alkaline phosphatase (ALP) and phosphate (Pi) in both serum and environmental samples with detection limits of 0.076 U/L and 0.025 μM, respectively. Moreover, we successfully employed the SSA-Tb-ATP ICPs to perform cellular imaging of ALP in both hepatocellular carcinoma cells (HepG2) and normal liver cells (LO2), representing a significant advancement in ALP detection and imaging. The simplicity of the synthesis and high sensitivity make this probe a promising tool for early diagnosis of hepatocellular carcinoma in clinical settings and environment analysis.

An intelligent “chemical tongue” for high-order monitoring ATP-related physiological phosphates and ATP hydrolysis through diverse transduction principles

For discriminating diverse analytes and monitoring a specific chemical reaction, the emerging multi-channel “chemical nose/tongue” is challenging multi-material “chemical nose/tongue”. The former contributes greatly to integrating different transduction principles from a single sensing material, avoiding the need for complex design, high cost, and tedious operation involved with the latter. Therefore, this high-order sensing puts a particular emphasis on the effects of encapsulation. Herein, the plasmonic gold nanoparticles (Au NPs) are encapsulated as a core into the fluorescent guanine monophosphate-Tb3+ infinite coordination polymer nanoparticles (GMP-Tb ICPs) to obtain a core-shell nanocomposite named Au NPs@GMP-Tb ICPs. Hence, a dual-channel “chemical tongue” based on Au NPs@GMP-Tb ICPs is present to realize high-order sensing of adenosine triphosphate (ATP)-related physiological phosphates and the monitoring of ATP hydrolysis. Considering the affinity of Tb3+ towards P–O bonds, four inorganic phosphates and three nucleotide phosphates with different phosphate group numbers and steric hindrance effect directly regulate two stimulus responses (fluorescence intensity and UV–vis absorbance) of Au NPs@GMP-Tb ICPs. Robust statistical methods, such as linear discriminant analysis and hierarchical cluster analysis, are used to recognize each phosphate by the developed sensor array either in the aqueous solution or in complex media such as serum, together with efficiently monitored ATP hydrolysis at different intervals. These findings and blind test clarify that the designed “chemical tongue” guarantees interference resistance and strengthens analytical capacity, together with offering valuable insight into “lab-on-a-nanoparticle” development for monitoring specific chemical reactions.

Chemodynamic therapy agent optimized mesoporous TiO2 nanoparticles for Glutathione-Enhanced and Hypoxia-Tolerant synergistic Chemo-Sonodynamic therapy

Sonodynamic therapy (SDT) can generate reactive oxygen species to kill cancer cells by activating sonosensitizers under ultrasound (US) irradiation. Nevertheless, its application is greatly limited by low quantum yield of sonosensitizers, high levels of endogenous glutathione (GSH) and tumor hypoxia. Herein, a GSH-activated sonosensitizers with synergistic therapy effect (chemodynamic therapy (CDT) and SDT) are developed by depositing Fe(III)-artemisinin infinite coordination polymers (Fe(III)-ART CPs) in pores of mesoporous TiO2 nanoparticles (NPs). The formed Fe(III)-ART-TiO2 NPs have high sono-induced electron-hole separation efficiency because the deposited Fe(III)-ART CPs can provide isolated intermediate bands to capture sono-induced electrons in TiO2 NPs. Meanwhile, Fe3+ in Fe(III)-ART-TiO2 NPs are reduced to Fe2+ by GSH with oxygen-deficient sites generated to further capture sono-induced electrons in TiO2 NPs. Based on this, the reaction efficiency between water molecules and sono-induced holes is high enough to generate numerous hydroxyl radicals (•OH) without oxygen participated for overcoming tumor hypoxia. Additionally, through consuming GSH, the generated Fe2+ can catalyze ART to produce C-centered free radicals for CDT. Owing to these characteristics, Fe(III)-ART-TiO2 NPs show significant tumor suppression ability and good biocompatibility in vivo. The strategy of using CDT agent to modify sonosensitizers offers new options to improve SDT effect without introducing harmful substances.

Doxorubicin-Fe(III)-Gossypol Infinite Coordination Polymer@PDA:CuO2 Composite Nanoparticles for Cost-Effective Programmed Photothermal-Chemodynamic-Coordinated Dual Drug Chemotherapy Trimodal Synergistic Tumor Therapy.

To achieve the maximum therapeutic effects and minimize adverse effects of trimodal synergistic tumor therapies, a cost-effective programmed photothermal (PTT)-chemodynamic (CDT)-coordinated dual drug chemotherapy (CT) trimodal synergistic therapy strategy in chronological order is proposed. According to the status or volumes of the tumors, the intensity and time of each therapeutic modality are optimized, and three modalities are combined programmatically and work in chronological order. The optimal synergistic therapy begins with high-intensity PTT for 10 min to ablate larger tumors, followed by medium-intensity CDT for several hours to eliminate medium-sized tumors, and then low-intensity coordinated dual drugs CT lasts over 48 h to clear smaller residual tumors. Composite nanoparticles, made of Fe-coordinated polydopamine mixed with copper peroxide as the cores and their surface dotted with lots of doxorubicin-Fe(III)-gossypol infinite coordination polymers (ICPs), have been developed to implement the strategy. These composite nanoparticles show excellent synergistic effects with the minimum dose of therapeutic agents and result in nearly 100% tumor inhibition for mice bearing PC-3 tumors and no observed recurrence within 60 days of treatment. The ratios of the different therapeutic agents in the composite nanoparticles can be adjusted to accommodate different types of tumors with this cost-effective programmed trimodal therapy strategy.

Isomorphous and Isostructural Coordination Polymers Besides Metal‐Organic Frameworks (MOFs) of bis(4‐Nitrophenyl)‐phosphoric Acid in Conjunction with Some N‐donor Compounds

AbstractVarious coordination complexes, in the form of infinite coordination polymers and metal‐organic frameworks (MOFs) of an organophosphorous acid, bis(4‐nitrophenyl)phosphoric acid (BNPP), in the presence of some N‐donor compounds like 4,4′‐bipyridine (bpy), 1,2‐bis(4‐pyridyl)ethene (bpyee), 1,2‐bis(4‐pyridyl)ethane (bpyea) and 1,3‐bis(4‐pyridyl)propane (bpypa) along with metal ions, Co+2, Cd+2, Cu+2, and Ni+2, have been reported. Using the single crystal X‐ray diffraction method, the obtained structures are classified into isomorphous, isostructural coordination polymers, and metal‐organic framework structures. Except for the structures, formed by bpy with Ni(II) and Cu(II), bpypa with Cu(II) and bpyee with Co(II) and Ni(II), all of the complexes crystallize with both BNPP and N‐donor ligands forming coordinate bonds with the metal ions, yielding dumbbell‐shaped moieties in the lattices. A noteworthy feature in the structures obtained with bpyee, is that BNPP molecules do not form coordination bonds with metal ions Co(II) and Ni(II), while N‐donor ligands (bpyee) are only connected to the metal ions. Furthermore, in these complexes, the BNPP molecules occupy the same positions in the crystal lattice as those of coordinated BNPP moieties, but by hydrogen bonds, thus, establishing a high correlation of isostructurality in three‐dimensional packing between structures having coordinated and uncoordinated BNPP molecules, and highlighting the significance of hydrogen bonds in comparison with coordinated bonds. All of the complexes described, herein, are stabilized by different types of intermolecular interactions, specifically through a large number of C−H⋅⋅⋅O hydrogen bonds. Hirshfeld analysis further demonstrates surface properties and establishes accountability of various intermolecular interactions towards the stabilization of the complexes, emphasising, in particular, the importance of the C−H⋅⋅⋅O hydrogen bonds

Self-healing and shape-adaptive nanocomposite hydrogels with anti-inflammatory, antioxidant, antibacterial activities and hemostasis for real-time visual regeneration of diabetic wounds

Diabetic severe wounds are difficult to heal and regenerate, and are extremely challenging to manage in clinical practice with common wound dressings. There is a need to develop multifunctional dressings that meet the requirements for efficient treatment of diabetic wounds. Therefore, the nanocomposite hydrogel with oxidized chondroitin sulfate (OCS), carboxymethyl chitosan (CMC), and phenol red-modified ε-poly-l-lysine (EPL-PR) as the backbones, encapsulated with chondroitin sulfate-modified selenium nanoparticles (CS@SeNPs) and infinite coordination polymer nanomedicine (ICPs) composed of procyanidins, berberine hydrochloride and Fe(III), was designed and fabricated. The prepared nanocomposite hydrogel system allows for rapid in situ gelation and complete coverage of irregular wounds. In vivo and in vitro investigations demonstrate that the nanocomposite hydrogel shows excellent tissue adhesion, antibacterial activities, biocompatibility and free radical scavenging properties. The rapid hemostasis of the nanocomposite hydrogel is confirmed through hemorrhage models of liver and caudal amputation. All the advantages enable the nanocomposite hydrogel to effectively induce skin tissue remodeling, promote vascular and hair follicle regeneration, remove free radicals from wounds, and accelerate wound healing. The nanocomposite hydrogel can also successfully monitor the pH range of 5–10, thus enabling real-time visual monitoring of the wound healing phase, facilitating wound management in clinical settings. This multifunctional wound dressing opens up ideas for the treatment and management of diabetic full-thickness wounds.

Fluorescent Probes Based on Metal and Aggregation-induced Luminescent Organic Molecule Complexes for Bioimaging and Sensing Applications

Metal-Organic Coordination polymer (MOCPs) is an emerging class of inorganic-organic porous hybrid materials with infinite coordination polymers (CPs) or metal-organic backbones (MOFs) formed by the interaction between metal ions and organic ligands and ligand functional groups. The molecular structure of the organic ligands composing MOCPs is rich in variation, while inorganic metal ions generally have good photoelectromagnetic properties. Therefore, MOCPs have diverse structural variations, adjustable pore size, high stability and controllable synthesis, and have received wide attention in gas storage, multiphase catalysis, chemical sensing and biological applications. Fluorescence properties are one of the most widely used techniques for bioimaging and sensing detection. However, conventional luminescent groups are usually affected by aggregation-induced quenching (ACQ) effects. Aggregation-induced luminescence molecules (AIEs) based on metal-organic coordination polymers combine the advantages of organic AIEs and transition metal centers to improve photophysical properties and therapeutic effects.

A luminescent sensor based on in-situ formed copper nanocluster-loading terbium coordination polymer with multicolor response for identification of antibiotics

Identification of multiple antibiotics is of great interest owing to the requirement of food safety and pollution control in environment. Herein, a multicolor luminescent sensor (GT-GC) was designed based on an infinite coordination polymer (GT) formed by guanosine monophosphate (GMP) and lanthanoid ions Tb3+ as host matrix, and in-situ formed copper nanoclusters (CuNCs, GC) formed by glutathione and Cu2+ as guest species. TEM and SEM images showed that CuNCs further aggregated under the host-guest interaction. As a result, the as-prepared GT-GC not only emit characteristic luminescence of Tb3+ at 490, 544, 586 and 620 nm, but also emit the luminescence of CuNCs at 631 nm due to AIE effect. In addition, including the intrinsic luminescence of antibiotics in GT-GC at about 439 nm, the GT-GC exhibits 6-channel luminescence originated from three luminescence centers of Tb3+, CuNCs and antibiotics. In this work, 26 antibiotics were well identified based on the luminescence responses of the GT-GC and consequent linear discrimination analysis (LDA). The unknown antibiotics in real samples were also successfully identified. Due to the multi-color variation of GT-GC upon the addition of antibiotics, the visual on-site rapid detection of antibiotics was realized by a smartphone installed color recognition program.

Au/Lum/RhB@Ag-DMcT ICP-Based Double-Ratio Colorimetric and Fluorometric Dual Mode Assay and Multi-Responsive Coffee Ring Chips for Point-of-Use Analysis of Phosphate Ions.

In this work, by fully exploring the stimulus response of the guest-functionalized infinite coordination polymers (ICPs), a double-ratio colorimetric and fluorometric dual mode assay and multi-responsive coffee ring chips for point-of-use analysis of phosphate ions (Pi) were proposed. First, the complex host-guest interactions were rationally designed to obtain Au/Lum/RhB@Ag-DMcT ICPs. The composite ICPs exhibited a purple-blue color resulted from the modulated localized surface plasmon resonance (LSPR) of the Au core, and a blue fluorescence color stemmed from the unique aggregation-induced-emission (AIE) of Luminol (Lum) and the aggregation-caused-quenching (ACQ) of rhodamine B (RhB). With the presence of Pi, the host-guest interactions of the shell within Au/Lum/RhB@Ag-DMcT ICPs were interrupted to release Au core, Lum, and RhB in a dispersed state. Consequently, the color of the solution changed to purple-red (the mixed color of the Au core and RhB guest), and the fluorescence color turned to orange-red (AIE of Lum decreased, while the ACQ of RhB recovered). This constituted the sensing mechanism for dual-mode Pi assay with the double ratiometric response. Second, during the stimulus response, the surface wettability/size/amount of Au/Lum/RhB@Ag-DMcT ICPs simultaneously altered. These changes were reflected in the form of the coffee ring deposition pattern variances on the glass substrate and served as signal readouts for the exploration of multi-responsive coffee ring chips for the first time. Quantitative Pi detection with high accuracy and reliability in real samples was thereby realized, which offered an opportunity for the point-of-use analysis of Pi in resources-limited areas in a high-throughput fashion.

Thermal conversion of infinite coordination polymers to europium-doped yttrium oxide microspheres

• •Y 2 O 3 :Eu 3+ microspheres were obtained by calcinating infinite coordination polymers. • •A relatively low temperature (550 °C) could be used for the thermal conversion. • •An increase of luminescence intensity could be observed after calcination. • •The particles were sliced using focused ion beam (FIB) and studied by SEM. We report the synthesis and thermal conversion of an infinite coordination polymer (ICP) based on the pyrazole-3,5-dicarboxylate linker, malonate coordination modulator, and Y 3+ metallic matrix doped with 5 % of Eu 3+ . The ICP particles exhibited spherical morphology and diameters between 1.0 and 3.0 µm. Then, this sample was subjected to a calcination process in order to obtain luminescent Y 2 O 3 :Eu 3+ particles with the same spherical morphology but with smaller diameters overall (<1.5 µm). A focused ion beam (FIB) was used to slice the particles and observe their insides using SEM. While the precursor ICP particles exhibit a smooth and massive interior, the calcinated Y 2 O 3 :Eu 3+ particles show internal channels and cracks due to the combustion of the organic components. The combination of excellent luminescent behavior, spherical shape, microsize, and presence of internal channels can lead to multifunctional Y 2 O 3 :Eu 3+ microparticles for biomedicine, photonics, and catalysis applications.

A strategy of “fluorescence-visualization dual channel” for highly sensitive and rapid detection of phosphate biomarkers based on stimulus-responsive infinite coordination polymers

The novel stimulus-responsive host-guest nanoparticles were prepared based on lanthanide infinite coordination polymer ([email protected]) for rapid and point-of-care analysis of phosphate (Pi) biomarkers. The obtained [email protected], which have the host-guest structure, were applied to high-sensitive detection of Pi biomarkers by the means of ratiometric “fluorescence-visualization dual channel”. The established method has the advantages of low detection limit (51 nM), wide linear range (0.25–5 μM) and rapid response to Pi within 3 min. The developed sensor was used to detect Pi in normal human urine and serum samples, with the recoveries of 96.04–106.3%. Furthermore, the fluorescent color changes of [email protected] from blue to red can be used to visually inspect Pi by the naked eyes. More importantly, a portable test strip based on [email protected] was fabricated and successfully applied to the rapid visual detection of Pi in human urine and serum samples.

Fluorogenic detection of mercury ion in aqueous environment using hydrogel‐based AIE sensing films

AbstractA “turn‐on” fluorescent sensing strategy was developed for ultrasensitive detection of heavy metal mercury ion (Hg2+) directly in water. It utilized an aqueous soluble aggregation‐induced emission (AIE)‐active probe, named 1,1,2,2‐tetrakis(4‐(1H‐tetrazol‐5‐yl)phenyl)ethene (TPE‐4TA), composing of a luminescent tetraphenylene core and multiple anionic tetrazolate spawns. The probe retained dark when molecularly dissolved in water. However, mercury ions can ligate with multiple tetrazolate groups to form infinite coordination polymer particles spontaneously, thus inducing a fluorogenic AIE response for in situ analysis. Moreover, by embedding this AIE sensing molecules in a hydrophilic polyvinyl alcohol substrate, the resulting hydrogel film allowed in situ detection of Hg2+ on a laser‐induced fluorescence analysis setup in aqueous environment. This strategy worked effectively in common aqueous environments with pH from 4 to 7.5 and showed high sensitivity (limit of detection down to 0.38 ppb/1.9 nM), good selectivity and a wide linearity range for quantification. This work may lead to a reliable and promising platform for on‐site environmental water analysis.

Detection of anthrax biomarker and metallic ions in aqueous media using spherical-shaped lanthanide infinite coordination polymers

We report a lanthanide-based infinite coordination polymer (ICP) system synthesized using pyrazole-3,5-dicarboxylic acid as linker, malonic acid as coordination modulator and water as solvent. The precursors self-assembly into microspherical particles, which are water-stable and exhibit excellent dispersibility. Bimetallic samples based on Tb3+ doped with Eu3+ were investigated as ratiometric dipicolinic acid (DPA) sensors, which is a biomarker for Bacillus anthracis spores. Along with the calibration curves, a detection in a real sample extracted from Bacillus subtilis (model organism) was performed. The samples proved to be highly sensitive and selective for ratiometric DPA detection. In a secondary study, the monometallic sample containing only Tb3+ was also investigated as a sensor for ionic species in aqueous media. The Cr3+, Fe3+, Cu2+, and Cr2O72− ionic species could be detected in water by luminescence quenching mechanism. Therefore, we found that the reported ICP system can be judiciously constructed in order to act as a multimodal probe for several chemical species.

PH-Regulated Terbium(III) Infinite Coordination Polymer Sensor Array for Pattern Discrimination of Quinolone Antibiotics

In this study, dual-ligand lanthanide metal–organic infinite coordination polymer (BDC-NH2-Tb-AMP ICPs) with dual fluorescence emission was constructed. Considering that quinolone antibiotics can sensitize Tb3+ luminescence, the diverse fluorescence responses for different antibiotics on Tb3+ at various pH’s are distinct due to their structures. Inspired by these facts, a fluorescent sensor array, in which the pH-regulated BDC-NH2-Tb-AMP ICPs acted as the sensing element, was proposed for the pattern recognition of five representative quinolone antibiotics using principal component analysis. Furthermore, the sensor array can realize the detection of environmental quinolone antibiotics in real samples, confirming its reliability and practicality in complex conditions. More broadly, by using the simple yet powerful strategy of pH regulation, the presented sensor array holds a great ability for efficiently distinguishing quinolone antibiotics, which provides an approach for point-of-care monitoring of residual antibiotics in the environmental field.

Electrochemical post-treatment of bimetallic-ICP/RGO precursor for Z-scheme CuOx·Ag2O/RGO hetero-structure with catalytic activity enhancement for visible-light-driven photo-Fenton degradation of tetracycline

In this work, rationally designed bimetallic infinite coordination polymer (ICP) was mixed with reduced graphene oxide (RGO) to serve as precursors for the preparation of CuOx·Ag2O/RGO hetero-structure. As the growth of metal oxide nuclei within the ICP network was restricted and more surface-oxygenated species of RGO were exposed during the electrochemical post-treatment process, the CuOx·Ag2O NPs supported on RGO were evenly-distributed nanoparticles with ultra-small size (2.89 ± 0.37 nm), which exhibited excellent catalytic activity enhancement in visible-light-driven photo-Fenton degradation of the model antibiotic tetracycline (TC). Moreover, since the CuOx·Ag2O/RGO was in-situ decorated on ITO glass, recycling of the catalysts with long-term stability could be realized, even after 5 cycles, 91.4 % of TC (10 mL, 50 mg/L) could be degraded within 60 min. A series of characterization and experiment results demonstrated the improved catalytic performance of CuOx·Ag2O/RGO for photo-Fenton degradation was stemmed from the synergistic effect of the components within the catalyst, which facilitated solar energy absorption, accelerated the separation of photo-generated hole-electron pairs through Z-scheme charge transfer way, and strengthened their mechanical stability on the substrate. This newly created catalysts for photo-Fenton reaction are of great potential to achieve the practical treatment of antibiotics-contaminated wastewater.