Fatimah Al-Zahrani

A visible-light photocatalytic approach for TiO₂ activation is presented using a phenothiazine–quinolinium cationic dye as a molecular photosensitizer. To minimize self-sensitization artifacts and improve mechanistic interpretation, phenol, a colorless and non-photosensitizing pollutant, was selected as the target contaminant. The pre-synthesized dye was adsorbed onto commercially available TiO₂ without further modification of the TiO₂ crystal lattice or metal doping. Under the employed white-LED irradiation and mild aqueous conditions, the system achieved approximately 70% phenol removal within 60 min. The experimental data were reasonably described by an apparent pseudo-first-order kinetic model (k ≈ 0.01478 min⁻¹). Radical-scavenging experiments provided indirect evidence for the involvement of hydroxyl- and superoxide-related reactive species. Control experiments showed that dark adsorption, direct phenol photolysis, and the activity of bare TiO₂ contributed only minimally under the investigated conditions, supporting a sensitization-assisted photocatalytic process. Supernatant analysis and four-cycle reuse experiments indicated predominantly heterogeneous behavior and short-term operational stability, with no substantial sensitizer release detectable by the applied UV–Vis method. The overall observations are consistent with a proposed sensitization-assisted pathway involving dye excitation, possible interfacial electron transfer to TiO₂, oxygen reduction, and reactive oxygen species formation. The mechanistic interpretation is presented in accordance with the experimental evidence available in the present study. The results demonstrate the potential of molecular dye sensitization as an approach for extending the photocatalytic response of TiO₂ under white-LED irradiation toward the removal of colorless organic contaminants from water.

Cancer is one of the major causes of death worldwide. The number of pathways and enzymes is involved in cancer proliferation and metastasis. One such enzyme is dihydrofolate reductase (DHFR). DHFR is an essential enzyme in DNA synthesis by catalyzing the reduction of dihydrofolate to tetrahydrofolate, which, in turn, is used in the biosynthesis of nucleotides, hence serves as an attractive target for the treatment of cancer. Therefore, this study aims to identify potential inhibitors through a combination of tandem structure‐based screening of an in‐house database of natural and synthesized compounds. This approach yielded compound Qth‐90 (2‐(3,4‐dihydroxyphenyl)chromane‐3,5,7‐triol) as a seed for the design of novel inhibitors. The inhibitory potential of the seed molecule was further evaluated through in vitro biochemical assays, demonstrating 90.64% inhibition with IC50 value of 11.10 ± 0.24 μM. To enhance the inhibitory potential of the seed molecule, the molecule was subjected to the deep learning web server WADDIACA for the generation of de novo molecules. A total of 100 novel molecules were generated using a trained artificial intelligence model employing deep learning–based de novo approaches, derived from the seed molecule. Among the 100 generated compounds, the top two were selected on the basis of their high synthetic accessibility (SA) score of 66.5578 and 99.00, respectively, along with optimum ADMET properties, lower docking scores, stronger binding interaction, and minimum binding free energy. These compounds exhibited relative activity similar to the seed molecule and are expected to serve as potential DHFR inhibitors, paving the way for further advanced studies.

In this work, a selective membrane for antibiotics removal from water was fabricated. The ingredients utilized for membrane fabrication include functionalized TiO₂ nanoparticles (NPs), poly methyl methacrylate (PMMA) and poly vinyl imidazole (PVIM). Firstly, TiO₂ nanostructure’s surface was functionalized through APTES. The layer of functional monomers methyl methacrylate (MMA) and VIM (vinyl imidazole) was grafted onto TiO₂ surface through controlled radical polymerization technique. The grafted material was fabricated into membrane with embedded selectivity utilizing molecular imprinting method. The material was diagnostically analyzed with Fourier Transform Infrared-Attenuated total reflection (FTIR-ATR) spectroscopy and NMR (Nuclear Magnetic Resonance) technique, which confirm functionalization of nanomaterial surface. The grafted layer around the nanoparticles was visualized with FESEM. The hybrid membrane shows excellent and promising results against removal of antibiotics from aqueous medium. The fabricated membranes via Molecular imprinted polymer (MIP) technique were applied for the selective removal of antibiotics (ciprofloxacin) from real water samples. The removal efficiency and selectivity of the hybrid membrane was monitored via UV visible spectroscopy.

The green-chemical preparation of silver nanoparticles (AgNPs) offers a sustainable and environmentally friendly alternative to conventional synthesis methods, thereby representing a paradigm shift in the field of nanotechnology. The biological synthesis process, which involves the synthesis, characterization, and management of materials, as well as their further development at the nanoscale, is the most economical, environmentally friendly, and rapid synthesis process compared to physical and chemical processes. Ligustrum ovalifolium flower extract was used for the preparation of AgNPs. The synthesized AgNPs were examined by using UV–visible spectroscopy, XRD, SEM, and TEM analysis. It indicates that AgNPs were formed in good size. AgNPs were applied as a catalyst for the degradation of pollutants, such as methyl orange, Congo red, and methylene blue, which were degraded within 8–16 min. Additionally, the reduction of para-nitrophenol (PNP) to para-aminophenol (PAP) was achieved within 2 min. This work demonstrates a practical, reproducible, and efficient method for synthesizing cost-effective and stable AgNPs, which serve as active catalysts for the rapid degradation of hazardous organic dyes in an aqueous environment.

Introduction: The cellular and molecular pathways of α-lipoic acid’s (ALA’s) protective effect were assessed against diclofenac (DIC) hepatorenal injury in vivo and against a pro-inflammatory stimulus in vitro . Material and Methods: The injury was induced in 28 adult male Wistar rats weighing 130–160 g by a single intraperitoneal injection of DIC (50 mg per kg body weight (b.w.)) on the fifth day. Seven positive control rats had received no hepatorenally protective compounds. Oral 100 mg/kg b.w. doses of silymarin (SLY) were given to seven animals, 50 mg/kg b.w. doses of ALA to seven more and 100 mg/kg b.w. doses of it to another seven for five days before DIC insult. Seven negative control rats received only distilled water instead of protective compound and in the injection. The anti-inflammatory effect of ALA was also assayed in murine RAW264.7 macrophage cells. Results: In the cells, ALA was antioxidant and anti-inflammatory in a dose-dependent manner, reducing nitric oxide (NO) and reactive oxygen species generation with half maximal concentrations of 7.8 and 6.25 μg/mL, respectively. Both ALA doses and SLY protected the hepatorenal tissues and improved kidney and hepatic functions compared to the organs of the positive control group. Additionally, ALA reduced oxidative stress biomarker levels in hepatic and renal tissues compared to the positive control rats. It also improved liver and kidney histology, where hepatic lesions were fewer, and protected renal architecture. Immunohistochemical analysis showed ALA to reduce caspase-3 expression, supporting its hepatorenal anti-apoptotic effect. Alpha lipoic acid markedly upregulated the hepatorenal messenger RNA expressions of nuclear factor erythroid 2-related factor 2 ( Nrf2 ), haem oxygenase-1 and nicotinamide adenine (phosphate) reduced form : quinone oxidoreductase 1, suggesting that the Nrf2 signalling pathway was enhanced. Conclusion: These findings suggested potential therapeutic benefits for ALA in mitigating DIC-induced hepatorenal toxicity through its anti-inflammatory, antioxidant and Nrf2-mediating effects. Future investigations are warranted to explore the synergistic interactions and multiomics mechanisms.

Application of the synthesized phenothiazine-thiosemicarbazide probe for optical solid-state detection of Hg²⁺ and Cu²⁺.

In this study, tulsi and neem oils were used to effectively synthesise Ag/Fe ₂ O ₃ /TiO ₂ nanocomposite utilising environmentally friendly methods. X-ray diffraction analysis (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy, and Fourier-transform infrared spectroscopy (FT-IR) methods were used to characterise the green synthesised nanocomposite. The triangle-spherical shaped nanoparticles (NPs) with an average size of 26–42 nm were shown by XRD and SEM investigations to be crystalline in Ag/Fe ₂ O ₃ /TiO ₂ nanocomposite, respectively. Additionally, the dynamic light scattering histogram was used to quantify the size distribution of these NPs, and the results were consistent with those of the SEM picture, having an approximate element size of 28 nm. The Ag/Fe ₂ O ₃ /TiO ₂ nanocomposite is reduced and stabilised as a result of functional groups present in acacia, and neem, and tulsi oils, as shown by FT-IR measurements. In a nutshell, this method offers a quick, affordable, and environmentally safe technique to create NPs without the use of potentially dangerous chemical agents.

Cancer stands as a significant global cause of mortality, predominantly arising from the dysregulation of key enzymes and DNA. One strategic avenue in developing new anticancer agents involves targeting specific proteins within the cancer pathway. Amidst ongoing efforts to enhance the efficacy of anticancer drugs, a range of crucial medications currently interact with DNA at the molecular level, exerting profound biological effects. Our study is driven by the objective to comprehensively explore the potential of two compounds: (7S,9S)-7-[(2R,4S,5S,6S)-4-amino-5-hydroxy-6-methyloxan-2-yl]oxy-6,9,11-trihydroxy-9-(2-hydroxyacetyl)-4-methoxy-8,10-dihydro-7H-tetracene-5,12-dione (A01) and 5-fluoro-1H-pyrimidine-2,4-dione (A02). These compounds have demonstrated marked efficacy against breast and cervical cancer cell lines, positioning them as promising anticancer candidates. In our investigation, A01 has emerged as a particularly potent candidate, with its potential bolstered by corroborative evidence from lactate dehydrogenase release and caspase-3 activity assays. On the other hand, A02 has exhibited remarkable anticancer potential. To further elucidate their molecular mechanisms and interactions, we employed computational techniques, including molecular docking and molecular dynamics simulations. Notably, our computational analyses suggest that the A01-DNA complex predominantly interacts via the minor groove, imparting significant insights into its mechanism of action. While earlier studies have also highlighted the anticancer activity of A01, our research contributes by providing a deeper understanding of its binding mechanisms through computational investigations. This knowledge holds potential for designing more effective drugs that target cancer-associated proteins. These findings lay a robust groundwork for future inquiries and propose that derivatives of A01 could be synthesized as potent bioactive agents for cancer treatment. By elucidating the distinctive aspects of our study’s outcomes, we address the concern of distinguishing our findings from those of prior research.