Commercial wastewater disinfection technologies are inadequate for achieving rapid, durable, and energy-efficient pathogen removal, particularly against high loads of E. coli in sewage treatment plant (STP) effluents. In this context, we have developed an engineered material comprising 1-(carboxymethyl)pyridin-1-ium (IL-5)-functionalized polyethylenimine (PD5) and Ag nanoparticles (PD5-Ag) via sigma/pi-d band interactions. After analyzing its biosafety by cytotoxicity analysis, it was integrated into a chitosan/poly(vinyl alcohol) (CHPV) matrix at varying concentrations. The combined effect of electron modulation of Ag by PD5 via sigma/pi-d band interactions and integration with the CHPV matrix enhances its electrocatalytic activity, rapid reactive oxygen species (ROS) generation, and minimum catalyst loss. The optimized PD5-Ag/CHPV-4 matrix demonstrated high electrochemically active surface area, low Tafel slope, and minimal Ag leaching. Moreover, it achieved complete E. coli inactivation within 8 min through a "latch-kill-detach" mechanism and retained 94.7% efficacy after 200 cycles. It effectively disinfected the STP effluent, thereby highlighting its practical applicability as an energy-efficient electro-disinfection platform for safe municipal water reuse.

Abstract Inorganic nanoparticles are widely used as sacrificial templates for the synthesis of porous carbons due to their good thermal stability, characteristic shapes, tunable sizes, compatibility with carbon precursors, and lower cost and toxicity than conventional silica‐based templates. Their use not only ensures the development of hierarchical porosity but also the creation of short‐range graphitic domains in the carbon matrix. These qualities make porous carbons suitable for different applications, including adsorption, separation, catalysis, and energy storage and conversion. Within the series of inorganic nanoparticle templates, metal oxides such as MgO, ZnO, Fe2O3, Fe3O4, and MnO2, and alkali metal salts such as NaCl and KCl stand tall as templates. They are thermally and structurally stable, do not react with the carbon precursor, and do not require high‐cost, harsh removal methods such as HF washing. This review provides up‐to‐date discussions of metal oxides (MgO, ZnO, Fe2O3, Fe3O4, and MnO2) and metal salts (NaCl, KCl, and composite salts) to produce porous carbons and addresses other aspects of their structures. This is a focused review that critically analyzes the recently published literature and will serve as a guiding framework for the future design and development of porous carbons.

A novel azo dye-based Schiff base receptors 1 and 2 were designed and synthesized via a sequence of steps and characterized by 1H NMR and single crystal X-ray crystallography. The cation recognition properties of receptor 2 were systematically investigated using fluorescence spectroscopy. Notably, receptor 2 displayed a distinct "turn-off" fluorescence response that was highly selective towards Fe3+ ions, with no significant interference from other tested cations. The binding studies revealed a detection limit as low as 2.5 mu M, demonstrating the high sensitivity of receptor 2. Furthermore, the practical applicability of receptor 2 was validated by successfully determining Fe3+ levels in a pharmaceutical drug sample. These findings highlight the design synthesis of new receptor 2 as a promising, cost-effective fluorescent receptor for the selective detection of Fe3+ ions.

Sunlight-driven photocatalytic reactors for wastewater treatment have become a growing hot topic among researchers owing to their inexpensiveness, scalable potential, and minimal ecological impact. Herein, we have utilized 3D printing to fabricate a packed bed reactor (PBR) consisting of an open serpentine channel packed with zinc oxide nanoparticles (ZnO) coated onto silica nanoparticles (SiO2) incorporated on cellulose nanocrystals (CNC) that is ZnO@SiO2@CNC. This developed PBR overcomes the expensive and time-consuming limitations of batch reactors with continuous flow mass treatment of persistent organic pollutants, including methylene blue (MB), Congo red (CR), and ciprofloxacin (CIP). The PBR exhibits remarkable removal efficiency that is further enhanced with increasing turbulence, reaching 99% and 98% for MB and CR, respectively, in just 20 min. Moreover, its potential for the photocatalytic degradation of the CIP antibiotic drug was confirmed with a removal efficiency of 81% in 110 min. The hybrid system was further explored for single-run operation and showed a degradation capacity of 99% for both MB and CR. The nanocomposite applicability to degrade these dyes at different pH levels and degradation pathways was also analyzed. Additionally, similar performance in degrading these persistent pollutants spiked in tap and river water confirmed its environmental applications for real samples.

Thymidine analogues are widely used as antiviral and anticancer agents; however, improper dosage and prolonged exposure can lead to severe hematological and genetic complications, necessitating reliable methods for their detection and discrimination. We report an array-based fluorescence sensing platform for the discrimination of structurally related thymidine analogues in aqueous media using a Pd-modified ZnO-polymer nanocomposite as a single cross-reactive probe. The nanocomposite was synthesized by functionalizing ZnO nanoparticles with a KG3 polymer matrix followed by palladium ion modification, and its structure and morphology were confirmed using standard spectroscopic and microscopic techniques. Distinct fluorescence response patterns were generated upon interaction with different thymidine analogues, enabling their effective differentiation through multivariate statistical analysis. Principal component analysis (PCA), linear discriminant analysis (LDA), hierarchical clustering analysis (HCA), and support vector machine (SVM) classification demonstrated reliable discrimination with high accuracy across the analyte set. The sensor array exhibited sensitive fluorescence responses with limits of detection in the range of 6-100 μM. This approach demonstrates the potential of single-probe fluorescence sensor arrays combined with pattern-recognition algorithms for the discrimination of closely related nucleoside analogues in complex chemical environments.

The widespread use of organophosphate pesticides, especially Fenitrothion (FNT), in agricultural practices has raised serious environmental and health concerns. Even at trace levels, it can cause toxic effects through inhalation, ingestion, or dermal exposure, contributing to an estimated 2 million poisoning cases and 10,000 deaths annually. This growing threat highlights the urgent need for effective detection and remediation technologies. For this, we designed an organic cation (DM3)-intercalated interfacial heterostructure, DM3-ZnO/FeOCl. The selective response of DM3-ZnO/FeOCl toward the detection of FNT has been established through spectroscopic and electrochemical techniques. It acts as a smart FNT-responsive material that targets and degrades FNT from contaminated water and soil. Moreover, a cost-effective DM3-ZnO/FeOCl-embedded poly(vinyl alcohol)/polyethylene glycol matrix (FenitroPur) has been developed as a portable system for the degradation of FNT in real-world scenarios. Mechanistic insights reveal that the degradation of FNT follows pseudo-first-order kinetics, achieving >99% degradation through a Recognize-Catalyze-Degrade mechanism. The role of radical species has been studied by using radical scavenger assays, and consequently, a degradation pathway has been evaluated. This work provides an environmentally friendly and sustainable solution for FNT removal from soil and water, thereby ensuring overall well-being.

Concerns about environmental contamination and food safety are driving the need for fast, sensitive, and simple screening methods. Conventional analytical methods are highly accurate and reliable, but their routine use is limited due to complex instrumentation, labor-intensive sample preparation, and centralized laboratory facilities. By integrating the multidimensional response capability of array-based sensing systems with the catalytic adaptability of nanozymes, colorimetric nanozyme sensor arrays have emerged as a promising sensing paradigm. Unlike traditional single-analyte sensors, nanozyme sensor arrays rely on interactions between analytes and multiple catalytic components to generate unique colorimetric response patterns. Differences in catalytic activity, substrate affinity, and surface interactions enable these cross-reactive platforms to produce distinct visual fingerprints, allowing differentiation of chemically similar targets. Advances in catalytic engineering—including heteroatom doping, defect engineering, surface functionalization, morphology control, and construction of metal-, carbon-, MOF-, COF-, and hybrid nanozyme architectures—have enhanced catalytic efficiency, selectivity, and signal diversity, improving array performance. The analytical capability of these systems is further strengthened by pattern-recognition methods such as principal component analysis (PCA), linear discriminant analysis (LDA), and artificial neural networks (ANNs). These techniques enable accurate classification and quantitative analysis of toxic analytes by interpreting differences in absorbance spectra, and RGB/HSV features. This paper reviews the design principles, catalytic strategies, and sensing mechanisms of colorimetric nanozyme sensor arrays for detection of food and environmental pollutants. Lastly, prospects for next-generation high-performance nanozyme sensor arrays enabling rapid, reliable, and intelligent food and environmental monitoring are outlined, along with key challenges, emerging opportunities, and future directions.

We report the structural and bactericidal properties of the imidazolium ionic liquid (IL)-based micelles of Thymus capitatus (thyme) essential oil (EO). The formation of micelles was investigated by contact angle measurements, which revealed a critical micelle concentration (CMC) of 2.5-3 µM for the IL mixed with thyme at 0.2 µL mL-1. The size, stability and self-assembly of EO-IL micelles in water were evaluated by the dynamic light scattering technique. It was determined that the self-dispersed micelles with a ∼400 nm diameter remained stable in a water environment for at least 6 months from their formation. The bactericidal properties of micelles investigated against S. aureus and E. coli under liquid-to-liquid conditions revealed a 6-log reduction in the bacterial concentration from 108 CFU mL-1 following 1 min exposure. Minimal bactericidal growth of both bacteria was observed under the CMC conditions. These results demonstrate the potential of EO-IL micelles as natural agents that self-disperse in water and kill bacteria at rapid rates.

Expression of concern for 'Synthesis and characterization of a novel copper carboxylate complex and a copper complex-coated polyether sulfone membrane for efficient degradation of methylene blue dye under UV irradiation: the single crystal X-ray structure of the copper carboxylate complex' by Rupy Dhir et al., Dalton Trans., 2024, 53, 9441-9451, https://doi.org/10.1039/D4DT00871E.

Pollutant residues such as pharmaceuticals or pesticides in water bodies pose significant environmental and health risks, necessitating the development of advanced sensing and removal techniques to ensure safe and sustainable water resources. Tb-based luminescent sensors offer high sensitivity for pollutant residue analysis, but their application is often limited to detection. Developing Tb-derived metal-organic gel (ANS-4G-Tb) as soft supramolecular material is proposed to enhance trace contamination removal, integrating both sensing and sequestration capabilities. For the development of the self-assembled supramolecular material, ANS-4, a low molecular-mass organic gelator (LMOG) with a molecular weight of just about 215 g/mole, was selected, owing to its efficient single-step synthesis, and it was comprehensively characterized using single crystal XRD, and other routine spectroscopic techniques. Then, its nanosized ANS-4G-Tb metallogel was characterized using a comprehensive suite of analytical techniques to assess its structural, chemical, morphological, and optical characteristics. Upon interaction with parasiticide and fungicide thiabendazole (TBZ), a phase transformation from gel to sol is observed, enabling naked-eye detection and simultaneous turn-on photo-luminescence sensing (5D4→7F5 transition). Based on novel research, our study navigates through the photo-luminescence of lanthanide supramolecular complexes, transitioning from fundamental investigations to potential methodologies concerning analyte responsiveness and removal applications.

A multicomponent Biginelli reaction was used to produce biologically active dihydropyrimidones that were then combined with ZnO nanoparticles.

In the field of environmental monitoring, there remain considerable challenges regarding the development of selective chemosensors with high sensitivity for detecting transition metal ions in aqueous media. In this study, we prepared and investigated 1,3-bis((2-((E)-(2-(pyridin-2-yl)hydrazineylidene)methyl)-1H-pyrrol-1-yl)methyl) benzene as a pyridine-hydrazone-based probe (receptor A) for the selective detection of metal ions. Upon interacting with Cu2+ and Co2+ ions, the probe responded with significant optical changes, thereby facilitating simple ion detection. The ultraviolet-visible absorption maximum of the receptor A underwent a remarkable hypsochromic shift to 291 nm upon the addition of Cu2+ solution, while the addition of Co2+ solution led to a bathochromic shift to 426 nm. Receptor A was capable of selectively detecting Cu2+ and Co2+ in aqueous solutions without any marked interference from other metal ions, with respective limits of detection of 2.12 × 10-6 and 3.47 × 10-8 M, which are significantly lower than the WHO guidelines. The ability of receptor A to detect Cu2+ and Co2+ in real water samples was also demonstrated. These findings highlight the potential utility of pyridine-hydrazones as an effective probe for real-time monitoring of Cu2+ and Co2+ ions in environmental samples.

This study presents the synthesis of a novel binuclear Cu(II) carboxylate complex under ambient laboratory conditions. The complex possesses a paddle wheel structure in which the axial positions are occupied by bromide/nitrate ligands. The synthesized complex was characterized using single-crystal X-ray crystallography, FT-IR, X-ray diffraction, and UV-Visible spectroscopic techniques. The thermal stability of the metal complex was studied through thermogravimetric analysis. The synthesized metal complex was employed for the synthesis of metal complex-coated polyether sulfone (PES) membranes, which were characterized before and after filtration using the FESEM technique. The photocatalytic efficiency of the metal complex for the degradation of methylene blue dye under UV irradiation in the presence of H2O2was studied and compared with the photodegradation efficiency of the metal complex-coated polyether sulfone (PES) membrane.

Cereals, grains, and feedstuffs are prone to contamination by fungi during various stages from growth to storage. These fungi may produce harmful mycotoxins impacting food quality and safety. Thus, the development of quick and reliable methods for on-site application is crucial for ensuring food safety and quality monitoring. Herein, we have developed an efficient sensor array based on hierarchically modified metal oxides with azodye-based metal complexes for on-site detection and segregation of harmful mycotoxins present in corn samples. The functionalized material has been fully characterized utilizing various sophisticated techniques. The sensor array successfully detected and differentiated five different mycotoxins with 100 % efficiency, validated by linear discriminant analysis (LDA) score plots. The limit of detection, as determined from calibration curves, ranges from 0.02 to 0.09 ppm for the respective mycotoxins. Additionally, the sensor array has also demonstrated 100 % accuracy in discriminating binary and ternary ratios of mycotoxins in real sample analyses.