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Photoactive complexes of bioessential 3d metals, activable within the phototherapeutic window (650–900 nm), have gained widespread interest due to their therapeutic potential. Herein, we report the synthesis, characterization, and light-enhanced anticancer and antibacterial properties of four new dinuclear Co(II) complexes: [Co(phen)(cat)]2 (Co-1), [Co(dppz)(cat)]2 (Co-2), [Co(phen)(esc)]2 (Co-3), and [Co(dppz)(esc)]2 (Co-4). In these complexes, phen (1,10-phenanthroline) and dppz (dipyrido[3,2-a:2′,3′-c]phenazine) act as neutral N,N-donor ligands, while cat2− and esc2− serve as O,O-donor catecholate ligands derived from catechol (1,2-dihydroxybenzene) and esculetin (6,7-dihydroxy coumarin). Their high-spin paramagnetic nature and dimeric identity in solution were confirmed by magnetic susceptibility, UV-visible, emission, and mass spectral data. Co-1–Co-4 exhibited an absorption band within the 600–850 nm range, originating from a charge transfer transition. The electrically neutral complexes demonstrated sufficient solution stability both in the dark and under irradiated conditions. The dppz complexes Co-2 and Co-4 exhibited notable toxicity towards A549 lung carcinoma cells, with potency increasing significantly under brief (5 min) exposure to 660 nm (red) and 808 nm (NIR) laser light (IC50 ∼ 8.9 to 14.9 μM). Notably, their toxicity towards normal NIH-3T3 fibroblast cells was minimal. Cellular assays highlighted that the induced cell death followed an apoptotic pathway, primarily due to mitochondrial damage. Co-2 and Co-4 also demonstrated significant antibacterial potency against Gram-(+) S. aureus and Gram-(−) P. aeruginosa, with effectiveness significantly enhanced upon 808 nm laser irradiation (MIC ∼ 15–142 μM). The increase in the anticancer and antibacterial efficacies was attributed to the generation of cytotoxic singlet oxygen (1O2) species upon red/NIR light exposure. Notably, 808 nm NIR irradiation produced more pronounced effects compared to 660 nm. This study is the first to report on cobalt complexes exhibiting red and NIR light-triggered enhancement of antibacterial and anticancer activities, illuminating the path for the development of long-wavelength absorbing cobalt complexes with enhanced therapeutic efficacy. [ABSTRACT FROM AUTHOR]

In biological systems, nitrite reductase enzymes (NIRs) are responsible for reduction of nitrite (NO2−) to nitric oxide (NO). These NIRs have mostly Cu- or Fe-containing active sites, surrounded by amine-containing ligands. Therefore, mononuclear Cu complexes with N-donor ligands are highly relevant in the development of NIR model systems and in the mechanistic investigation of the nitrite reduction reaction. Herein, we report on a terpyridine-based CuII complex with square planar geometry for H+-assisted electrochemical reduction of NO2−. Through electrochemical measurements, spectroscopic characterization and isotope-labelling experiments we propose a mechanistic reaction pathway involving an unstable HNO2 state. The CuI intermediate, formed electrochemically, was isolated and its molecular structure was deduced, showing linkage isomerism of the nitrite ligand. Moreover, qualitative and quantitative product analysis by GC-MS shows N2O formed as a side product along with the main product NO. Furthermore, by obtaining single crystals and conducting structural analysis we were able to determine the structural arrangement and redox state of the complex after electrochemical treatment. [ABSTRACT FROM AUTHOR]

Activating photosensitizers with long-wavelength excitation is an important parameter for effective photodynamic therapy due to the minimal toxicity of this light, its superior tissue penetration, and excellent spatial resolution. Unfortunately, most Ir(III) complexes suffer from limited absorption within the phototherapeutic window, rendering them ineffective against deep-seated and/or large tumors, which poses a significant barrier to their clinical application. To address this issue, several efforts have been recently made to shift the absorption of Ir(III) photosensitizers to the deep-red/near-infrared region by using different strategies: functionalization with organic fluorophores, including porphyrinoid compounds, and ligand design via π-extension and donor–acceptor interactions. In this Frontier, we highlight such new developments and the ongoing challenges in this field. [ABSTRACT FROM AUTHOR]

Localized cancer therapies such as radiotherapy, phototherapy, and chemotherapy are precise cancer treatment strategies aimed at minimizing systemic side effects. However, cancer metastasis remains the primary cause of mortality among cancer patients in clinical settings, and localized cancer treatments have limited efficacy against metastatic cancer. Therefore, researchers are exploring strategies that combine localized therapy with immunotherapy to activate robust anti-tumor immune responses, thereby eradicating metastatic cancer. Biomaterials, as novel materials, exhibit great potential in biomedical applications and have achieved great progress in clinic translation. This review introduces biomaterials and their applications in research focused on enhancing localized cancer treatment activated anti-tumor immunity. Additionally, the current challenges and future directions of biomaterials are also discussed, providing insights and references for related research. [ABSTRACT FROM AUTHOR]

Bacterial infections pose an increasingly serious threat to global health due to the development of drug-resistant strains. Developing a method to efficiently kill bacteria and promote tissue repair is imperative to decrease the damage from bacterial infection, especially infected wounds. Herein, a biofriendly and light-controlled nitric oxide (NO) generator HFB with simultaneous bacterial killing and wound repair properties is reported based on a tailored light-responsive molecule F(EIBC)2. HFB demonstrates an appropriate photothermal conversion efficiency of 33.4% and type I reactive oxygen species (˙OH and H2O2) generation capability to simultaneously trigger NO generation and potently kill bacteria. Furthermore, HFB can effectively eradicate mature bacterial biofilms with the aid of favorable permeability of NO. Additionally, HFB effectively eradicates Staphylococcus aureus in infected wounds of living mice and accelerates healing via NO-induced angiogenesis and collagen deposition. Owing to the encapsulated human serum albumin (HSA), heavy metal-free feature, and synergistic killing mechanism, HFB exhibits good biosafety to surrounding tissue and major organs. This work provides a novel dual-functional photo-responsive molecule and a potential light-controlled release platform for the treatment of bacterial infections. [ABSTRACT FROM AUTHOR]

Herein, the computer-guided design, chemical synthesis, and biological evaluation of a Ru C polypyridine complex, that could eradicate cancerous cells upon excitation with red light at 630 nm, is reported. [ABSTRACT FROM AUTHOR]

Bioelectronics is a hot research topic, yet an important tool, as it facilitates the creation of advanced medical devices that interact with biological systems to effectively diagnose, monitor and treat a broad spectrum of health conditions. Electrical stimulation (ES) is a pivotal technique in bioelectronics, offering a precise, non-pharmacological means to modulate and control biological processes across molecular, cellular, tissue, and organ levels. This method holds the potential to restore or enhance physiological functions compromised by diseases or injuries by integrating sophisticated electrical signals, device interfaces, and designs tailored to specific biological mechanisms. This review explains the mechanisms by which ES influences cellular behaviors, introduces the essential stimulation principles, discusses the performance requirements for optimal ES systems, and highlights the representative applications. From this review, we can realize the potential of ES based bioelectronics in therapy, regenerative medicine and rehabilitation engineering technologies, ranging from tissue engineering to neurological technologies, and the modulation of cardiovascular and cognitive functions. This review underscores the versatility of ES in various biomedical contexts and emphasizes the need to adapt to complex biological and clinical landscapes it addresses. [ABSTRACT FROM AUTHOR]

A homologous series of azobenzene-derived photo-switchable ion relay transporters is reported. We reveal that both the length and geometry of the relay strongly affect transport rate, allowing the relative activity of the E and Z isomers to be reversed and hence the wavelengths of light used for on and off switching to be exchanged. [ABSTRACT FROM AUTHOR]

Despite the fact that the surface tension of liquid mixtures is of great importance in numerous fields and applications, there are no accurate models for calculating the surface tension of solutions containing water, salts, organic, and amphiphilic substances in a mixture. This study presents such a model and demonstrates its capabilities by modelling surface tension data from the literature. The presented equations not only allow to model solutions with ideal mixing behaviour but also non-idealities and synergistic effects can be identified and largely reproduced. In total, 22 ternary systems comprising 1842 data points could be modelled with an overall root mean squared error (RMSE) of 3.09 mN m−1. In addition, based on the modelling of ternary systems, the surface tension of two quaternary systems could be well predicted with RMSEs of 1.66 mN m−1 and 3.44 mN m−1. Besides its ability to accurately fit and predict multi-component surface tension data, the model also allows to analyze the nature and magnitude of bulk and surface non-idealities, helping to improve our understanding of the physicochemical mechanisms that influence surface tension. [ABSTRACT FROM AUTHOR]

The synthesis of eight Ru(II) and Os(II) photosensitizers bearing a common 9,10-disubstituted-1,4,5,8-tetraazaphenanthrene backbone is reported. With Os(II) photosensitizers, the 9,10-diNH2-1,4,5,8-tetraazaphenanthrene could be directly chelated onto the metal center via the heteroaromatic moiety, whereas similar conditions using Ru(II) resulted in the formation of an o-quinonediimine derivative. Hence, an alternative route, proceeding via the chelation of 9-NH2-10-NO2-1,4,5,8-tetraazaphenanthrene and subsequent ligand reduction of the corresponding photosensitizers was developed. Photosensitizers chelated via the polypyridyl-type moiety exhibited classical photophysical properties whereas the o-quinonediimine chelated Ru(II) analogues exhibited red-shifted absorption (520 nm) and no photoluminescence at room temperature in acetonitrile. The most promising photosensitizers were investigated for excited-state quenching with guanosine-5′-monophosphate in aqueous buffered conditions where reductive excited-state electron transfer was observed by nanosecond transient absorption spectroscopy. [ABSTRACT FROM AUTHOR]

Ultrahigh resolution mass spectrometry hyphenated with liquid chromatography (LC) is an emerging tool to explore the isomeric composition of dissolved organic matter (DOM). However, matrix effects limit the potential for semi-quantitative comparison of DOM molecule abundances across samples. We introduce a post-column infused internal standard (PCI-IS) for reversed-phase LC-FT-ICR MS measurements of DOM and systematically evaluate matrix effects, detector linearity and the precision of mass peak intensities. Matrix effects for model compounds spiked into freshwater DOM samples ranging from a headwater stream to a major river were reduced by 5–10% for PCI-IS corrected mass peak intensities as compared to raw (i.e., untransformed) intensities. A linear regression of PCI-IS corrected DOM mass peak intensities across a typical DOM concentration range (2–15 mg dissolved organic carbon L−1) in original, non-extracted freshwater samples demonstrates excellent linearity of the detector response (r2 > 0.9 for 98% of detected molecular formulas across retention times). Importantly, PCI-IS could compensate for 80% of matrix effects across an environmental gradient of DOM composition from groundwater to surface water. This enabled studying the ionization efficiency of DOM isomers and linking the observed differences to the biogeochemical sources. With PCI-IS original, non-extracted DOM samples can be analysed by LC-FT-ICR MS without carbon load adjustment, and mass peak intensities can be reliably used to semi-quantitatively compare isomer abundances between compositionally similar DOM samples. [ABSTRACT FROM AUTHOR]

Transition metal selenides and sulfides have attracted much attention as supercapacitor electrode materials, and reasonable construction and modification strategies can effectively improve their actual energy storage capacity. Herein, a CuCoSe@NiS/NF electrode material was optimized from the two dimensions of the material structure and microstructure using a self-supported bimetallic CuCo-MOF template and surface modification. The in situ growth not only secures the structural integrity of the electrode material but also eliminates the unwanted internal resistance, thereby enhancing the material's conductivity. The distribution of different spaces of the nanosheets greatly increased the specific surface area of the material, which endowed it with sufficient electrochemical active sites, thus obtaining the desired electrochemical performance. The strong electronic interactions between the CuCoSe nanosheets and NiS sheet layers significantly increased the charge transport rate. Consequently, the specific capacitance of the prepared CuCoSe@NiS/NF material reached a satisfactory specific capacitance of 2937.6 F g−1 at 1 A g−1. The assembled asymmetric supercapacitor (ASC) delivers a high energy density of 41.8 W h kg−1 at 800 W kg−1. This work provides insights for the rational construction of sulfur and selenium coexisting composite electrode materials and the optimisation of the electrode structures. [ABSTRACT FROM AUTHOR]

The photocatalytic Minisci reaction (PMR) is of great significance for fine chemical synthesis and the sustainable methodology of functionalized heteroarenes. However, the activity and stability of photocatalysts, as well as the selectivity of functionalized products, are the challenges of the current PMR, limiting its suitability for industrial production. Here, we report that a perylene-3,4,9,10-tetracarboxylic dianhydride/carbon nitride metal-free catalyst (PTCDA/g-C3N4) with a strong interfacial effect and steric selectivity can promote high separation of photogenerated carriers and selectivity of functionalized products. In the PMR model reaction of 4-methylquinoline with tetrahydrofuran, the elaborately designed PTCDA/g-C3N4 interface not only enables ˙O2− and ¹O2 species formation by weakening carrier recombination, but also promotes the formation of functionalized products instead of ring-open by-products of tetrahydrofuran by absorbing visible light. Importantly, PTCDA/g-C3N4 photocatalytic model reaction conversion and selectivity were up to 95% and 98.9%, respectively, in the presence of atmospheric O2 and blue LED irradiation. And, after PTCDA/g-C3N4 as reused four times, the activity of the model reaction showed no significant loss in its reactivity. Further electron paramagnetic resonance (EPR), kinetic isotope effect (KIE) and radical-trapping studies elucidated the reaction mechanism evolving active oxygen (O) radicals mediating the PMR to realize the C–H alkylation of heteroarenes. This investigation provides an innovative way to develop high-performance inorganic solid semiconductor photocatalysts for the PMR under visible light. [ABSTRACT FROM AUTHOR]

Cancer is considered as the biggest medicinal challenge worldwide. During a typical treatment, the tumorous tissue is removed in a surgical procedure and the patient further treated by chemotherapy. One of the most frequently applied drugs are platinum complexes. Despite their clinical success, these compounds are associated with severe side effects and low therapeutic efficiency. To overcome these limitations, herein, the synthesis and biological evaluation of Cu(II) terpyridine complexes as chemotherapeutic drug candidates is suggested. The compounds were found to be highly cytotoxic in the nanomolar range against various cancer cell lines. Mechanistic insights revealed that the compounds primarily accumulated in the cytoplasm and generated reactive oxygen species in this organelle, triggering cell death by apoptosis. Based on their high therapeutic effect, these metal complexes could serve as a starting point for further drug development. [ABSTRACT FROM AUTHOR]

In this study, self-supported NiFeP was fabricated on Ni mesh (NiFeP/NM) via a two-step monopulse electrodeposition and phosphorization strategy. The NiFeP/NM exhibited excellent activity through electrochemical surface reconstruction to generate true active sites, requiring low overpotentials of 349 mV and 310 mV to reach a current density of 500 mA cm-2 for the HER and OER, respectively, and exhibiting satisfactory stability in 6 M NaOH. [ABSTRACT FROM AUTHOR]

A hetero-bimetallic Ru(II)–Ir(III) photosensitizer was developed. Upon light exposure, contrary to the homogeneous Ru(II)–Ru(II) and Ir(III)–Ir(III) complexes that can only produce singlet oxygen, Ru(II)–Ir(III) can generate multiple reactive oxygen species and kill hypoxic tumors. This study presents the first example of a hetero-bimetallic type-I and type-II dual photosensitizer. [ABSTRACT FROM AUTHOR]

The development of photocatalysts plays a pivotal role in facilitating the production of green hydrogen energy through water splitting. In this study, one-dimensional (1D) organic–inorganic ZnCdS(EDA)/Ni@NiO (EDA: ethylenediamine) nanorods were prepared by combining organic molecules of EDA into ZnCdS. The EDA molecule possesses two amino functional groups with strong electron-donating capacity, thereby facilitating electron transfer to ZnCdS(EDA)/Ni@NiO and enabling efficient hydrogen evolution through photocatalytic water splitting. The H2 evolution rate of ZnCdS(EDA)/Ni@NiO was 159 μmol g−1 h−1 in the absence of sacrificial agents, and its H2 evolution rate in the system with EDA as the sacrificial agent can reach 5760 μmol g−1 h−1. The combination of EDA, a S vacancy, and heterojunction was proved to be the main factor for improving the separation and transfer rate of photogenerated carriers. The incorporation of ZnCdS(EDA)/Ni@NiO enhances the participation of photogenerated electrons in the photocatalytic hydrogen evolution reaction, thereby improving the overall photocatalytic activity. The synthesis of this one-dimensional composite catalyst holds great potential for advancing the development of efficient photocatalytic materials. [ABSTRACT FROM AUTHOR]

Photodynamic therapy (PDT) is promising for cancer treatment but still suffers from some limitations. For instance, PDT based on 1O2 generation (in a type-II mechanism) is heavily dependent on high oxygen concentrations and will be significantly depressed in hypoxic tumors. In addition, the residual photosensitizers after PDT treatment may cause severe side-effects under light irradiation. To solve these problems, herein a BODIPY (boron dipyrromethene)-modified Ru(II) complex [Ru(dip)2(tpy-BODIPY)]2+ (complex 1, dip = 4,7-diphenyl-1,10-phenanthroline, tpy = 2,2′:6′,2′′-terpyridine) was designed and synthesized. Complex 1 exhibited both high singlet oxygen quantum yield (Φ = 0.7 in CH3CN) and excellent superoxide radical (O2˙−) generation, and thus demonstrated efficient PDT activity under both normoxic and hypoxic conditions. Moreover, complex 1 is photo-degradable in water, and greatly loses its ROS generation ability after PDT treatment. These novel properties of complex 1 make it promising for efficient PDT under both normoxic and hypoxic conditions with reduced side-effects. [ABSTRACT FROM AUTHOR]

Luminescent lanthanide molecular compounds have recently attracted attention as potential photosensitizers (PSs) for photodynamic therapy (PDT) against malignant cancer tumours because of their predictable systemic toxicity, temporospatial specificity, and minimal invasiveness. A photosensitizer exhibits no toxicity by itself, but in the presence of light and oxygen molecules, it can generate reactive oxygen species (ROS) to cause damage to proteins, nucleic acids, lipids, membranes, and organelles, which can induce cell apoptosis. This review focuses on the latest developments in luminescent lanthanide-based molecular materials as photosensitizers and their applications in photodynamic therapy. These molecular materials include lanthanide coordination complexes, nanoscale lanthanide coordination polymers, and lanthanide-based nanoscale metal–organic frameworks. In the end, the future challenges in the development of robust luminescent lanthanide molecular materials-based photosensitisers are outlined and emphasized to inspire the design of a new generation of phototheranostic agents. [ABSTRACT FROM AUTHOR]

Due to the antitumor properties, Zn(II) complexes have attracted more and more attention. Herein, three novel tetranuclear Zn(II) complexes 1–3 based on dihydrazone pyrimidine derivatives H2L1–H2L3 were synthesized and characterized using IR spectroscopy, 1H NMR spectroscopy, single crystal X-ray diffraction analysis, XRD, TG and elemental analysis. Single crystal X-ray diffraction analysis revealed that 1–3 all displayed a [2 × 2] grid-like topology. The stability in solution, lipophilicity, confocal imaging and antitumor activities were investigated. Complexes 1–3 displayed high structural stability, membrane permeability and different lipophilicities. They can target mitochondria due to the cation charge. The MTT assay indicated that all of them exhibited stronger antiproliferative activity than the corresponding derivatives H2L1–H2L3 and the well-known cisplatin against all the selected tumor cells (BGC-823, BEL-7402, MCF-7 and A549), with IC50 values ranging from 2.83 μM to 7.97 μM. AO/EB double staining, flow cytometry and ROS detection suggested that complexes 1 and 2 could induce BGC-823 apoptosis in a dose-dependent manner. UV-Vis spectra, CD spectra, viscosity analysis and molecular docking revealed that complexes 1 and 2 interact with DNA mainly via partial intercalation and groove binding. Tetranuclear [2 × 2] grid-like Zn(II) complexes have the potential to be promising antitumor agents in the future. [ABSTRACT FROM AUTHOR]

Herein, we report a modular regioselective alkene difunctionalization strategy based on the use of hydrofluoroolefin (HFO) gas as fluorous feedstock material. The transformation of the HFO gas to iodonium salt creates vicinal electrophilic sites readily available for a broad range of nucleophiles. [ABSTRACT FROM AUTHOR]

Multi drug-resistant Gram-positive pathogens have become one of the most serious problems facing humankind today. To address this challenge, there is an urgent need to develop new antimicrobial agents that are different from conventional antibiotics. Here, a Ru-based compound bearing benzonitrile, [Ru(dtb)2(BZIL)2](PF6)2 (RuBZ), was synthesized and evaluated. In vitro antibacterial studies demonstrated that RuBZ could efficiently inhibit S. aureus in vitro, showing higher potency than most existing clinical antibiotics, with a minimum inhibitory concentration value of 0.78 μg mL−1. Importantly, RuBZ can effectively inhibit S. aureus from forming a biofilm and releasing hemolytic toxin. What is more, RuBZ exhibited synergistic effects when combined with four clinical antibiotics. Mechanism studies suggest that RuBZ kills bacteria by disrupting their cell membrane. In addition, RuBZ has low hemolytic toxicity and shows good anti-infective potency in two animal infection models. Above all, our study presented here indicates that the Ru-based compound containing a benzonitrile group shows good potential for use as a new anti-infective agent. [ABSTRACT FROM AUTHOR]

A platinum(IV) prodrug, cis,cis,trans-[Pt(NH3)2Cl2(biotin)(L)] (1), derived from cisplatin, where HL is the PEGylated red-light active boron-dipyrromethene (BODIPY) ligand, was synthesized, characterized and its photocytotoxicity evaluated. The complex showed a near-IR absorption band at 653 nm (ε ∼9.19 × 104 M−1 cm−1) in dimethyl sulfoxide and Dulbecco's phosphate-buffered saline (1 : 1 v/v) at pH 7.2. When excited at 630 nm, it showed an emission band at 677 nm in DMSO with a fluorescence quantum yield of 0.13. The 1,3-diphenylisobenzofuran titration experiment gave a singlet oxygen quantum yield (ΦΔ) of ∼0.32. A mechanistic DNA photocleavage study revealed singlet oxygen as the reactive oxygen species (ROS). The complex with biotin and PEGylated-distyryl-BODIPY showed significantly higher cellular uptake in A549 cancer cells as compared to non-cancerous Beas-2B cells from flow cytometry, indicating selectivity towards cancer cells. A dichlorodihydrofluorescein diacetate assay showed cellular ROS generation. Confocal images revealed predominant internalization in the mitochondria. The prodrug showed remarkable photodynamic therapy (PDT) activity in cancerous A549 and multidrug-resistant MDA-MB-231 cells with a high photocytotoxicity index value (half-maximal inhibitory concentration (IC50): 0.61–1.54 μM in red light), while being non-toxic in the dark. The chemo-PDT activity was significantly less in non-tumorigenic lung epithelial cells (Beas-2B). The prodrug effectively triggered cellular apoptosis, which was confirmed by the Annexin V-FITC/propidium iodide assay, and the alteration of the mitochondrial membrane potential was substantiated by the JC-1 dye assay. The β-tubulin immunofluorescence assay confirmed that incubating the cells with a light-treated complex resulted in the rapture of the cytoskeletal structure and the formation of apoptotic bodies. The results demonstrate that the prodrug triggered apoptosis via DNA damage, a reduction in mitochondrial function and disruption of the cytoskeletal framework. [ABSTRACT FROM AUTHOR]

We hereby engineered photoactivatable Pt(IV) metallodrugs that harness CD36 to target ovarian cancer cells. Pt(IV) compounds mimic the structure of fatty acids and take advantage of CD36 as a "Trojan horse" to gain entry into the cells. We confirmed that CD36-dependent entry occurs using graphite furnace atomic absorption spectroscopy with ovarian cancer cells expressing different levels of CD36 and a CD36 inhibitor, SSO. Once the Pt(IV) metallodrugs enter the cancer cells, they can be activated to form Pt(II) with characteristics of cisplatin under visible light (490 nm) irradiation, promoting photoinduced electron transfer from the attached fluorophore to the metal center. This light-induced activation can increase the cytotoxicity of the Pt(IV) metallodrugs by up to 20 times toward ovarian cancer cells, inducing DNA damage and enabling efficient elimination of drug-resistant cancer cells. [ABSTRACT FROM AUTHOR]