Luminescent Zinc Research Articles

AIE pyrene-based luminescent zinc MOF for selective and sensitive ATP and ADP sensing in water by analyte-induced structure decomposition

Adenosine triphosphate (ATP) is a natural and universal energy carrier that produces adenosine diphosphate (ADP) by releasing chemical energy through hydrolysis, which plays a key role in various biological processes. Hence, the design of probes for the selective ATP and ADP sensing among various nucleosides is significant. In this work, 4,4′-(pyrene-1,6-diyl)dibenzoic acid (H2PDBA) has been synthesized and shows an aggregation-induced emission (AIE) effect in a THF-H2O mixture at 10 % water fraction. Based on H2PDBA, a new zinc metal–organic framework (MOF), namely {[Zn(PDBA)]·2(CH3)2NH}n (Zn-MOF, PDBA = deprotonation of H2PDBA), has been constructed under hydrothermal conditions with a coordination-induced emission (CIE) effect. Significantly, Zn-MOF has been utilized to detect ATP and ADP in water with high selectivity and quick response time (within 1 min) by fluorescence quenching. The Ksv values and detection limits have been measured to be 7.83/8.78 × 103 M−1 and 0.82/1.71 μM for ATP and ADP, respectively. The sensing mechanism investigation indicates that the interactions between the ATP or ADP and Zn2+ nodes of the framework lead to the partial collapse of the framework, followed by the release of the ligand H2PDBA with weak luminescence in pure water. Moreover, Zn-MOF has successfully been applied for the determination of ATP and ADP with the recovery method by using fetal bovine serum samples.

Sustainable Fabrication of Luminescent Zinc Oxide Nanoparticles From Cucumis melo Fruit Peel Extract as Prospective Photocatalytic and Antigermicidal Agent.

The focus of current advances in nanotechnology has shifted significantly towards environmentally conscious methods that use harmless ingredients and moderated reaction circumstances to promote equitable development. Zinc oxide nanoparticles (NPs) currently grabbed attention of multiple medical fields owing to their unique ability to safeguard against cellular damage and alleviate serious human diseases via processes related to metabolism. This work focused on the generation of ZnO NPs using the peel of Cucumis melo fruit. The NPs were then analyzed and characterized using UV-Vis spectroscopy. The results indicated that at a wavelength of 352 nm, it was proven that the biosynthesis of ZnO NPs had occurred. The XRD pattern indicated the presence of dense crystal structures. The field emission scanning electron microscope (FE-SEM) picture confirmed the existence of polygonal-shaped ZnO NPs. The findings indicate that the produced ZnO NPs possess tough antibacterial properties against Gram-positive and Gram-negative microorganisms. When the ZnO NPs were exposed to direct sunshine for 80 min, they showed an 89% dye breakdown efficiency. This research specifically focused on the decomposition of reactivity dyes, with methylene blue dye being used as the target dye. The work demonstrates that the biosynthesis of ZnO NPs has a crucial and versatile role in the biological and environmental sectors.

Recent development of luminescent chemosensors for the recognition of nitroexplosives based on zinc(II) Schiff base complexes

In this review, we briefly summarize the key aspects of the synthetic strategies for zinc(II) Schiff base complexes, focusing on their photophysical properties such as the origin of luminescence, intensity, lifetime, and quantum yield. Additionally, we discuss the advantages of using luminescent zinc(II) complex-based sensors, the factors underlying their effectiveness as chemosensors for explosive detection, their mechanisms of action, and future outlooks and concerns. Most of the zinc(II) Schiff base complexes reported to date function as turn-off luminescent chemosensors for nitroexplosives. Some zinc(II) complexes discussed in this review demonstrate very high selectivity and sensitivity, with limits of detection (LOD) in the ppb or nM range for picric acid. Additionally, certain zinc(II) complexes can detect picric acid in the solid state through a visible color change observable to the naked eye under ambient light.

Poly-vinyl-pyrrolidone capped luminescent zinc oxide nanocomposites as excellent tools for germicidal and photo-catalytic performances.

Alternate antibiotics developed through the involvement of nanomaterials are gaining interest due to their economical and lower toxicity concerns. A newly developed biopolymer-based polyvinylpyrrolidone/zinc oxide (PVP/ZnO) nanocomposite (NCs) was efficiently synthesized by an environment-friendly approach, utilizing onion and garlic peel extract as a bio-surfactant, zinc acetate as the source, PVP as the stabilizing agent, and sodium hydroxide as the precipitant. Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD) investigations verified the crystalline properties of ZnO, PVP, and PVP/ZnO-based NCs. The structure of the biopolymer-linked ZnO particles interpolated inside the PVP array was seen to have a layered and flaky structure, as validated by field emission scanning electron microscopy (FE-SEM) analysis, which revealed its occurrence in the nanometer range. The XRD examination verified that the surface topographical image of PVP/ZnO NCs had an average thickness of 21 nm. The PVP/ZnO nanocrystals demonstrated exceptional photocatalytic efficacy, with a breakdown rate of 88% and almost 92% for the methylene blue dye. Therefore, the PVP/ZnO matrix exhibits superior antibacterial activity compared to other extracts, resulting in greater microbial suppression. The results above indicate that the ZnO-intercalated PVP array has a stronger reinforcing effect than other components. Hence, PVP/ZnO nanocrystals exhibit enormous potential as a favorable substance for environmental and biomedical intentions.

Polarity-Tunable Luminescence and Intersystem Crossing of a Zinc(II) Diimine Dithiolate Complex.

Combined density functional theory and multireference configuration interaction methods including spin-orbit interactions have been employed to investigate the photophysical properties and deactivation pathways of a zinc diimine dithiolate complex involving the phenanthroline derivative bathocuproine and the dianionic dithiosquarate as chelating ligands. Zn(batho)(dtsq) is one of the few luminescent zinc complexes for which triplet emission had been reported in the solid state [Gronlund, P. Inorg. Chim. Acta 1995, 234, 13-18]. Because of the high dipole moment of the complex in the electronic ground state, ligand-to-ligand charge-transfer (LLCT) states experience strong hypsochromic shifts in polar media, while ligand-centered (LC) states are nearly unaffected. Rate constants for the thermally activated upconversion of the TLLCT population to the SLLCT state are promising due to a small singlet-triplet energy gap and the participation of the sulfur in the electronic excitation, but the TLLCT state is not the lowest-lying excited triplet state in ethanol solution. In addition to the TLLCT electronic structure, TLC(batho)' and TLC(dtsq) ππ* excitations form minima on the T1 potential energy surface. The SLLCT luminescence is expected to be quenched at the nanosecond time scale by the dark TLC(dtsq)ππ* state. Moreover, a TLC(dtsq)σπ* state has been identified, which leads to degradation of the compound. In mildly polar media, the dark triplet LC states are energetically inaccessible and the lowest excited singlet and triplet states clearly exhibit an LLCT character. However, their mutual spin-orbit coupling is reduced to the extent that reverse intersystem crossing is not very likely at room temperature. While Zn(diimine)(dithiolate) complexes continue to be perceived as an interesting substance class with potential application as emitters in electroluminescent devices, the particular Zn(batho)(dtsq) complex is not considered suitable for that purpose.

Retraction notice to “Two superior luminescent zinc(II) coordination polymers sensors based on a bifunctional groups ligand: Detecting trace nitro explosive picric acid” [Inorg. Chem. Commun. 105 (2019) 240-246

Retraction notice to “Two superior luminescent zinc(II) coordination polymers sensors based on a bifunctional groups ligand: Detecting trace nitro explosive picric acid” [Inorg. Chem. Commun. 105 (2019) 240-246

A Luminescent Zinc(II) Coordination Polymer for Selective Detection of Fe3+ and Cr2O72− in Water and Catalytic CO2 Fixation

AbstractFluorescence‐based detection technique using coordination polymer has been considered an attractive alternative over conventional approaches. Herein, a new luminescent zinc(II) coordination polymer, [Zn(4‐ABPT)(NIPA)(H2O)], SSICG‐5, is synthesized by using a Lewis acidic Zn(II) ion, aromatic nitro group containing ligand 5‐nitroisophthalic acid (H2NIPA), and basic −NH2 rich ligand 3,5‐di(pyridine‐4‐yl)‐4H‐1,2,4‐triazol‐4‐amine (4‐ABPT). SSICG‐5 can detect Fe3+ and Cr2O72− selectively with a LOD of 0.16 μM and 1.94 μM, respectively. Additionally, carbon dioxide (CO2) fixation via one‐pot CO2 cycloaddition reaction has significant importance for reduced waste formation, minimizing reaction time and lowering chemical usage. Zn metal centre of SSICG‐5 possesses a replaceable coordinated water molecule. The active metal sites combined with the Lewis acidic and basic sites of the ligands make SSICG‐5 an ideal bifunctional heterogeneous catalyst for efficient CO2 cycloaddition reaction under room temperature (RT), solvent‐free conditions. Notably, SSICG‐5 exhibits near quantitative conversion (turnover number (TON) of 198) of propylene oxide to its carbonate compound under mild reaction conditions.

Fabrication of hydrophilic luminescent zinc oxide quantum dots for selective detection of copper ions and efficient inhibition of harmful fungi

In this study, we have successfully prepared surface modified zinc oxide quantum dots (M-ZnO QDs) with ultra-stable fluorescence and excellent hydrophilicity through introducing (3-aminopropyl)triethoxysilane (APTES). The as-prepared M-ZnO QDs under the optimum condition presented strong yellow fluorescence emission under 355 nm excitation and showed satisfied reproducibility. Physical and chemical properties of the synthesized ZnO QDs were further studied by various characterization techniques. Transmission electron microscopy showed homogeneous distribution of spherical M-ZnO QDs with the average particle size of 4.03 nm. According to the characteristic that metal ions can quench fluorescence, M-ZnO QDs-based fluorescence sensor for the detection of Cu 2+ in aqueous solution is developed in this work, which has the advantages of excellent selectivity, good sensitivity and a wide linear range. The limit of detection was 0.51 μM and the linear detection range was 1–200 μM for Cu 2+ determination. The practicability of the fluorescent probe is further validated in the lake water and the satisfactory spiked recoveries of Cu 2+ ranges from 99.1 % to 108.8 %. Besides, M-ZnO QDs displayed concentration inhibition effect and strain effect on the growth of fungi. Thus, the as-prepared M-ZnO QDs are demonstrated to be promising for Cu 2+ determination and anti-fungal applications.

Solvo-thermal synthesis of a unique cluster-based nano-porous zinc(II) luminescent metal-organic framework for highly sensitive detection of anthrax biomarker and dichromate

In this work a flexible multi-dentate 4,4′-(1H-1,2,4-triazole-1-yl) methylene-bis(benzonic acid) (H2L) ligand has been employed, a unique cluster-based nano-porous luminescent zinc(II) metal-organic framework {[Zn(μ6-L)]·(DMAC)2}n (1) (DMAC = Dimethylacetamide) has been isolated under solvo-thermal conditions. The H2L ligand adopts hexa-dentate coordination modes via one triazole nitrogen atom and four aromatic carboxylate oxygen atoms, which bridge the neighboring six-coordinated ZnII centers, leading to a three-dimensional (3D) nano-porous metal organic framework. A PLATON program analysis suggests the total potential solvent area volume is 2028.9 Å3, which occupy 62.5% percent of the unit cell volume (3248.4 Å3). PXRD Patterns of the as-synthesized samples 1 have been determined confirming the purity of the bulky samples. Photo-luminescent properties indicate strong fluorescent emissions of 1 at the room temperature. Further photo-luminescent measurements show that 1 can exhibit highly sensitive real-time luminescence sensing of anthrax biomarker dipicolinic acid (DPA) with high quenching efficiency (KSV = 1.48 × 105 M−1) and low detection limit (0.298 μM (S/N = 3)). Meanwhile 1 also exhibits highly selective and sensitive luminescence sensing for Cr2O72- ions in aqueous solutions with high quenching efficiency KSV = 1.22 × 104 L·mol−1 and low detection limit (0.023 μM (S/N = 3)). Therefore 1 can be used a unique multi-functional 3D cluster-based metal organic material in sensitive detection and effective detection of environment pollutants and biomarker molecules.

An ultra-thin flexible wearable sensor with multi-response capability prepared from ZIF-67 and conductive metal-organic framework composites for health signal monitoring.

Simulation of somatosensory systems in human skin with electronic devices has broad applications in the development of intelligent robots and wearable electronic devices. Here, we give an account of a new biomimetic flexible dual-mode pressure sensor, which is based on the first developed sea dandelion-like conductive metal-organic framework (cZIF-67@Cu-CAT) and the self-synthesized mechanically luminescent zinc sulfide nanoparticles and cleverly combines the microdome structure of the lotus leaf. According to finite element simulation analysis (FEA), the deformation behavior and pressure distribution of the contact interface with dandelion-like nanostructures cause the contact area of the sensor to increase rapidly and steadily with the load. It is for this reason that the piezoresistive pressure sensor has a high sensitivity of 71.74 kPa-1 over a wide range of 0.5 to 80 kPa. More importantly, it can roughly perceive stress changes in the external environment through mechanoluminescence materials without a power supply. The ultra-thin flexible pressure sensor is suitable for sensitive monitoring of small vibrations, including wrist pulse and joint motion. Combined with Bluetooth data transmission, it is not difficult to see that the high-sensitivity ultra-thin sensor designed in this study has broad potential in the applications of bio-wearable electronics and will play an immeasurable role in various sports training and joint protection in the future.

Synthesis, structure and fluorescence property of a new Zn-MOF based on a tetraphenylethane (TPE) ligand

A new 3D luminescent Zinc (II) metal-organic framework, has been solvothermally synthesized by using Zn(NO3)2⋅4H2O and a mixture of ligands: Titpe ligand and bcpf ligand. The molecular formula is [Zn(Titpe)(bcpf)•(DMF)]n, (Compound 1, Titpe = 1,1,2,2-tetrakis(4-(1H-imidazol-1-yl)phenyl)ethane, bcpf= 4,4΄-sulfonyldibenzoic acid). Compound 1 crystallizes in the triclinic system, space group P -1, with a=12.9990(9), b=14.2181(10), c=14.3781(10) Å, α = 89.974(4)°, β = 71.640(4)°, γ = 80.732(4)°, V = 2485.6(3) Å3, Z = 2, Mr = 1039.43, Dc =1.389 g/cm3, μ = 0.600 mm−1, F(000) = 1076.0, R = 0.0747 and wR =0.2508 for 9724 observed reflections (I > 2σ(I)). Topology analysis shows that compound 1 is a double interpenetrating structure. In addition, due to the ligand-to-ligand charge transfer of the TPE chromophore, luminescent spectra of 1 shows that it emits strong blue light. Compound 1 can detect Fe3+ ions with high selectivity and sensitivity among diverse inorganic cations in aqueous solution and is also a highly selective sensing material for CrO42− and Cr2O72- ions.

EPR study of paramagnetic centers in SiO2:C: Zn nanocomposites obtained by infiltration of fumed silica with luminescent Zn(acac)2 solution

Silica-carbon with zinc (SiO2:C:Zn) nanocomposites obtained via infiltration with aged luminescent zinc acetylacetonate (Zn(acac)2) ethanol solution of two concentrations (1 or 4%) into the fumed silica (SiO2) matrix have been studied using EPR within the temperature range 6…296 K before and after thermal annealing. The EPR spectrum of SiO2:C:Zn nanocomposites consists of three signals with the Lorentzian lineshape corresponding to paramagnetic centers with S = 1/2, which are related to carbon dangling bonds (CDB) (g = 2.0029(3)), silicon dangling bonds (g = 2.0062(3)) and oxygen-centered carbon-related radicals (CRR) (g = 2.0042(3)). A small EPR linewidth (<1 mT) observed for CDB and oxygen-centered CRR allows us to conclude that they are in the sp3-hybridized state. It was found that the temperature dependence of the EPR signal integrated intensity of the CDB and oxygen-centered CRR follows the Curie–Weiss law with a small positive value of the Curie–Weiss constant, which indicates that the weak ferromagnetic exchange interaction takes place in the spin system of CDB and oxygen-centered CRR. It was supposed that the carbon-related centers are clustered in SiO2:C:Zn nanocomposites. We assume that the oxygen-centered CRR in the sp3-hybridized state are associated with luminescent centers in previously reported aged Zn(acac)2/C2H5OH solution.

Dynamics of a bifunctional motor under crowded conditions

A simple and inexpensive fabrication of a polymer based bifunctional motor, containing catalytic palladium nanoparticles (Pd NPs) and luminescent zinc quinolate inorganic complex (Zn-QC), is reported. The motor displayed buoyancy driven self-propulsion in aqueous hydrogen peroxide (H2O2) solution, and could be easily tracked within liquid media using its luminescence under UV light. The propulsion speed and the luminescence of the motor were found to be correlated with the solution viscosity and local concentration of macromolecules within the medium. The bifunctional motor was further used to monitor bacterial concentration in solutions and was found to be an excellent probe for simultaneous characterization of spatio-temporal density and viscosity profiles of inhomogeneous solutions and particle assemblies. The motor fabricated is scalable and offers convenient platform for using self-powered catalytic motors in gleaning comprehensive insights into the rheology and density profiles of complex crowded systems, like the cytosol.

Synthesis and Photophysical Properties of Multi‐Functional Bisimidazolyl Phenol Zinc (II) Complex: Application in OLED, Anti‐Counterfeiting and Latent Finger Print Detection

Abstract+An aggregation‐induced emission‐based, luminescent Zinc (II) coordination complex of bisimidazolyl phenol (Zn‐BDI) is prepared. The thermal stability of the complex Zn‐BDI is attributed to the twisted conformation, and the rigid molecular structure of the ligand BDI resulted from the incorporation of the Zn‐metal atom. The maximum emission of the Zn‐BDI appears to be at 475 nm and emits strong cyan fluorescence. The light emission performance of the prepared zinc complex in organic light‐emitting diodes (OLEDs) indicates fairly good electroluminescence properties (max. brightness 13500 cd/m2, max. EQE=3.8 %). Moreover, these Zn‐BDI can emit strong cyan‐blue luminescence with a high quantum efficiency (0.83), and hence, latent fingerprint (LFPs) investigation exhibited permanent, immutable, and unique pores that are distributed on the ridges. Collectively, the prepared Zn complex offers a new avenue for the OLED and LFP applications.

Luminescent Zinc(II) Coordination Polymers of Bis(pyridin-4-yl)benzothiadiazole and Aromatic Polycarboxylates for Highly Selective Detection of Fe(III) and High-Valent Oxyanions

The hydro(solvo)thermal reactions of Zn(NO3)2·6H2O, bis(pyridin-4-yl)benzothiadiazole (BTD-bpy), and benzene-1,3,5-tricarboxylic acid (H3btc) or naphthalene-1,4-dicarboxylic acid (1,4-H2ndc) yielde...

Synthesis, Photoluminescence and Electrical Study of Pyrazolone-Based Azomethine Ligand Zn(II) Complexes.

New luminescent zinc complexes were obtained by reaction of pyrazolone-based azomethine ligands with Zn(CH3COO)2·2H2O. Complexes fully characterized by elemental analysis, FTIR, ES–MS, NMR, and single crystal X-ray analysis. Title complexes in the solid state demonstrate tunable luminescence from blue to orange by varying of substituents on the aromatic ring. Quantum yields are in the 0.03 to 0.49 range. TGA data shows that obtained complexes demonstrate high thermal stability and can be used as electroluminescent materials. The electrical properties of the complexes under study were considered in the ITO-Zncomplex-Al “sandwich” structure.

Solvothermal preparation of luminescent zinc(II) and cadmium(II) coordination complexes based on the new bi-functional building block and photo-luminescent sensing for Cu2+, Al3+ and L-lysine

In industry, over usage of Cu2+ and Al3+ will lead to toxic wastewater, which further to give serious pollution for the environment. On the other hand, L-lysine can enhance serotonin release in the amygdala, with subsequent changes in psychobehavioral responses to stress. Therefore it is the urgent problem to design a method for detecting the amount of Cu2+, Al3+, and L-lysine. In this work, through the solvothermal synthesis method, two new coordination complexes based on the new bifunctional building block 4′-(1H-1,2,4-triazole-1-yl)- [1,1′-biphenyl]-4-carboxylic acid (HL) have been synthesized, namely, [Zn(L)2·4H2O] (complex 1) and [Cd(L)2·4H2O] (complex 2). X-ray single-crystal diffractometer was used to analyze its structure, powder X-ray diffraction (PXRD) patterns confirmed that 1 and 2 powder’s purity and 1 can keep stable during the detection process of Cu2+, Al3+, and L-lysine, respectively. Elemental analysis, thermogravimetric analysis, infrared analysis, ultraviolet analysis and fluorescent spectrum have been used to characterize these complexes. The photo-luminescent test showed that 1 can accurately recognize Al3+ and Cu2+ among various cations. On the other hand, 1 can distinguish L-lysine among amino acid molecules. Therefore, 1 can be utilized as a multifunctional fluorescent probe for Al3+(Ksv = 1.5570 × 104 [M]−1), Cu2+(Ksv = 1.4948 × 104 [M]−1) and L-lysine (Ksv = 4.9118 × 104 [M]−1) with low detection limits (17.5 μM, 18.2 μM, 5.6 μM) respectively.

A luminescent zinc-organic framework as bifunctional chemosensors for detection of nitrobenzene and Fe3+

A luminescent zinc metal-organic framework with uncoordinated triazolate N-donors, namely [Zn (tba)2]·DMA (1, DMA ​= ​N,N-dimethylacetamide), has been successfully synthesized under solvothermal conditions by using a triazolate-carboxylate bifunctional ligand, 4-(1H-1,2,4-triazol-1-yl)benzoic acid (Htba). Single-crystal X-ray diffraction analysis reveals that compound 1 displays a 4-fold interpenetrating dia framework with 1D dumbbell-shaped channels. The systematic luminescence experiments reveal that 1 can be potentially used as a fast-response fluorescence sensor for the sensitive detection of nitrobenzene and Fe3+ ion through drastic fluorescence quenching. Moreover, the quenching mechanisms of 1 towards nitrobenzene and Fe3+ were also investigated.

Urothermal Syntheses of two New Luminescent Zinc(II) Compounds via Dual‐ligand Strategy

Urothermal reaction of Zn(NO3)2·6H2O, Htrz and NH2H2pdc or H2pdc affords two new compounds, namely [Zn2(NH2bdc)(trz)2]n·2n(e‐urea) (1) and [Zn4(bdc)2(trz)4(H2O)(e‐urea)]n·n(e‐urea) (2) (Htrz = 1,2,4‐triazole, NH2H2bdc = 2‐aminoterephthalic acid, H2bdc = terephthalic acid, e‐urea = 1,3‐ethyleneurea). X‐ray structural analyses revealed that both compounds 1 and 2 feature e‐urea‐templated 3D pillar‐layer framework with 2D ZnII‐triazole layer and 6‐connected pcu topological network. These two compounds not only have high thermal stabilities but also show intense luminescence at room temperature.

A novel DOTA-like building block with a picolinate arm for the synthesis of lanthanide complex-peptide conjugates with improved luminescence properties

Combination of complexes of lanthanide cations (Ln3+) for their luminescent properties and peptides for their recognition properties is interesting in view of designing responsive luminescent probes. The octadentate DOTA (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid) chelate is the most popular chelate to design Ln3+ complex-peptide conjugates. We describe a novel building block, DO3Apic-tris(allyl)ester, which provides access to peptides with a conjugated nonadentate chelate, namely DO3Apic, featuring a picolinate arm in place of one of the acetate arms compared to DOTA, for improved luminescence properties. This building block, with allyl protecting groups, is readily obtained by solid phase synthesis. We show that it is superior to its analogue with tBu protecting groups for the preparation of peptide conjugates because of the difficult removal of the tBu protecting groups for the latter. Then, we compare two luminescent zinc fingers (LZF) comprising (i) a zinc finger peptide for selective Zn2+ binding, (ii) a Eu3+ complex and (iii) an acridone antenna (ACD) for long-wavelength sensitization of Eu3+ luminescence. The first one, LZF3ACD|Eu, incorporates a DOTA chelate for Eu3+ whereas the other, LZF4ACD|Eu, incorporates a DO3Apic chelate. Both act as Zn2+-responsive luminescent probes but we show that changing DOTA for DO3Apic results in a higher Eu3+ luminescence lifetime and in a doubling of the quantum yield, confirming the interest of the DO3Apic chelate and the DO3Apic(tris(allyl)ester building block for the preparation of Ln3+ complex-peptide conjugates. Additionally, the DO3Apic chelate provides self-calibration for LZF4ACD|Eu luminescence upon excitation of its picolinamide chromophore, making LZF4ACD|Eu a ratiometric sensor for Zn2+.