The persistence of pharmaceuticals in aquatic environments poses an increasing threat to aquatic ecosystems and human health, as conventional wastewater treatment plants often fail to remove contaminants of emerging concern (CECs) effectively. This work offers a systematic comparative assessment of the photocatalytic activity of TiO₂, ZnO, CeO₂, Bi₂O₃, and WO₃ nanoparticles for degrading chloroquine phosphate (CLQ), a widely used antiviral and anti-inflammatory drug, under ultraviolet irradiation in ultrapure water, drinking water, and synthetic seawater. The semiconductors were thoroughly characterised for morphology, crystalline structure, optical bandgap, and surface charge. Reactive oxygen species (ROS) generation, including hydroxyl radicals (·OH) and singlet oxygen (¹O₂), was measured to clarify degradation efficiency in each matrix. TiO₂ demonstrated the highest photocatalytic efficiency, achieving up to 83% CLQ degradation in drinking water, consistent with its superior ROS production. ZnO and CeO₂ showed moderate activity, with performance significantly influenced by pH and ionic composition, while Bi₂O₃ and WO₃ remained suppressed, especially in complex water matrices. Overall, this study emphasises the importance of assessing photocatalysts under realistic environmental conditions and identifies TiO₂ as the most robust and adaptable semiconductor for removing CLQ, even in complex water matrices.

In the field of nanomedicine, nanoparticles have gained increasing attention due to their potential as therapeutic and diagnostic tools across a wide range of biomedical applications. However, despite their growing popularity and promising results, understanding their biological interactions and accurately evaluating their safety and efficacy remain significantly challenging. In this context, the invertebrate model organism Caenorhabditis elegans (C. elegans) provides an ideal toxicological model system because of its favorable characteristics. In this research, we used C. elegans to investigate the effects of potentially toxic iron-doped zinc oxide nanoparticles (ZnO NPs) and their biocompatible counterpart, lipid-coated ZnO (L-ZnO NPs). In addition, we combine these NPs with physical stimulation, i.e., ultrasound, to which these NPs are responsive, aiming to evaluate possible combined treatments in animals. The toxicity of ZnO and L-ZnO NPs was evaluated on this invertebrate model. In addition, external acoustic pressure stimulation was studied, evaluating the sole effects of ultrasound stimulation and its combined application with NPs. Multiple biological parameters were analyzed to assess treatment effects, including viability, biodistribution, egg-laying, body bends, and production of radical species associated with oxidative stress. This study demonstrates that L-ZnO NPs exhibit greater biological safety than ZnO NPs, while their combined application with ultrasound does not result in an additive effect. Additionally, the results highlight the potential of using C. elegans as a primary model to evaluate nanomedicine treatments and obtain initial insights into the effects of nanoparticles in animal systems.

In this study, we evaluate the physicochemical properties and the antioxidant, antimicrobial, anticancer, photocatalytic, and larvicidal activities of T. polium-mediated ZnO NPs. The synthesized ZnO NPs were characterized by UV-visible spectroscopy (absorption at 392nm), FTIR, TEM, and XRD, confirming their successful synthesis. The antioxidant activity of ZnO NPs was evaluated using various assays: DPPH scavenging at 54% (100µg/mL), ABTS scavenging at 63.3% (100µg/mL), FRAP scavenging at 61.2% (100µg/mL), and hydrogen peroxide scavenging at 65% (100µg/mL), demonstrating concentration-dependent activity. The antibacterial properties were tested against E. coli, P. aeruginosa, K. pneumoniae, and S. aureus, with the largest inhibition zone observed for P. aeruginosa (28.3mm at 100µg/mL). Cytotoxicity on MCF-7 cells showed a dose-dependent decrease in cell viability, with values of 75.6%, 44%, 20%, and 8% for concentrations of 25, 50, 75, and 100µg/mL, respectively. ROS generation and apoptosis were also observed at higher concentrations. The photocatalytic degradation of Methyl Orange was evaluated under UV irradiation, yielding 85% degradation efficiency at pH 3 with a ZnO NP concentration of 50mg/L. The larvicidal toxicity against Aedes aegypti was significant, with LC50 values of 76.63µg/mL for III instar and 82.74µg/mL for IV instar larvae. The results suggest that T. polium-mediated ZnO NPs possess significant potential for therapeutic applications, including antioxidant, antimicrobial, anticancer, photocatalytic, and larvicidal activities, making them a promising candidate for biomedical and environmental applications.

Engineering interfacial electronic interactions between physically distinct metal oxides without phase transformation, doping, or lattice fusion remains a central challenge of interface science. Conventional Cu2O-ZnO systems rely on heterojunction formation or compositional mixing, whereas carbon-mediated electronic coupling between discrete phases remains largely unexplored. Here, we report strongly electronically coupled carbon-bridged Cu2O/ZnO nanocomposites (Cu2O-C-ZnO NCs) synthesized by incorporating spherical Cu2O and diamond-shaped ZnO nanoparticles into a gallic-acid-derived carbon framework. Structural and compositional analyses confirm the coexistence of crystalline Cu2O and ZnO interlocked in a homogeneous carbon matrix, with oxygenated carbon functionalities verified spectroscopically. X-ray photoelectron spectroscopy reveals binding energy shifts in Cu and Zn core levels, providing direct evidence of interfacial electronic coupling and charge redistribution without lattice fusion or heterojunction formation. This electronic interface coupling helps regulate charge transfer between the oxide materials, allowing the controlled release of metal ions and enhancing the generation of reactive oxygen species. As a functional consequence, the NCs exhibit significant antibacterial activity against Gram-negative and Gram-positive bacteria, as well as substantial antialgal activity against freshwater species. Mechanistic evidence validates that the activity stems from a synergy of phenomena, including controlled ion release, ROS, and membrane damage due to oxidative stress, supported by findings from enzymatic and cellular assays. These results demonstrate that carbon-mediated interfacial electronic coupling is a viable method for controlling the surface reactivity of multicomponent oxide systems with the intact structural integrity of individual components.

Ultrasensitive detection of alpha-fetoprotein via ZnO-mediated photo-ATRP signal amplification on chitosan-functionalized magnetic beads.

Animal glue stains are commonly found in manuscripts, and their removal is a delicate process that requires selective treatment to avoid damaging the fragile cellulose fibers. Therefore, this study developed a novel hybrid double network hydrogel (HDNH) consisting of synthetic polymer (Polyacrylamide), natural polymers (Agarose or sodium alginate), and Zinc Oxide nanoparticles (ZnONPs) for removing animal glue stains from paper manuscripts. The cleaning mechanism relies on the capillary HDNH to draw the aged animal glue into the gel matrix. To establish the suitability of this HDNH as a paper-cleaning material, the gels were first characterized physicochemically and microstructurally, and the HDNH formulation was confirmed. At the same time, mechanical, physicochemical, morphological, optical, and wettability techniques were performed on the paper samples under investigation, both before and after the cleaning treatment, to evaluate the HDNHs’ cleaning capabilities. The results show that the Polyacrylamide/Agarose/ZnONPs (HDNH/Ag/ZnONPs) provide superior performance in removing most of the accumulated glue layers while maintaining the structural and chemical integrity of the paper substrate. Agarose provides a very rigid, highly porous structure with a superior capacity to retain water, preventing the paper from becoming waterlogged. Polyacrylamide provides flexibility and mechanical durability, allowing the hydrogel to be peeled off in one piece.Supplementary InformationThe online version contains supplementary material available at 10.1038/s41598-026-56366-z.

Diabetes mellitus is a global concern with complications including recurrent skin infections and poor wound healing. The involvement of multidrug-resistant bacteria (MDR) in skin infections renders them challenging. Nanoparticles such as silver, zinc oxide, and chitosan-based nanoparticles offer a promise for combating the growing threat of MDR bacteria by employing unique mechanisms that bypass recognized antibiotic resistance pathways. Therefore, this study reports the eco-friendly synthesis of silver (AgNPs), zinc oxide (ZnONPs), and chitosan-tripolyphosphate nanoparticles (Cs-TPP-NPs) using green tea extract (GTE) and gamma irradiation. AgNPs exhibited the highest antibacterial and antibiofilm efficacy among the tested preparations, as reflected by their lowest minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values against four bacterial strains associated with diabetic foot ulcers, including Pseudomonas aeruginosa, Escherichia coli, methicillin-resistant Staphylococcus aureus (MRSA), and Streptococcus pyogenes. The killing activity of AgNPs was fast acting against all tested bacteria with > 10 log10 CFU/mL reduction in 2–6 h. The AgNPs-GTE loaded Cs-TPP-NPs combination was assessed for possible mechanisms of action, which revealed its ability to inhibit biofilm formation and compromise bacterial membrane integrity in MRSA and E. coli, leading to increased permeability, intracellular ion leakage, and nucleic acid release. Notable morphological damage to bacterial cells was confirmed by transmission electron microscope (TEM). In vivo, the prepared combination hydrogel promoted healing of skin lesions in a CD1 mouse model of diabetic skin infection lesion within six days, demonstrating strong antibacterial activity with a 4 Log10 unit reduction in bacterial load compared with the untreated group, and significant decrease in inflammatory marker NF-kB, restoring it to healthy uninfected control levels. Histopathological evaluation of treated tissues showed full epidermal regeneration, enhanced fibroblast proliferation, increased angiogenesis, and the presence of well-organized mature collagen fibers in the dermis, compared to untreated controls. In conclusion, synthesized AgNPs-GTE loaded Cs-TPP-NPs combination offered an effective therapeutic approach for enhancing diabetic skin infection healing.Supplementary InformationThe online version contains supplementary material available at 10.1038/s41598-026-54908-z.

ZnO nanoparticles induce developmental delay in Caenorhabditis elegans via SLC-30A9-mediated ferritinophagy-ferroptosis axis.

Retraction notice to 'Characterization of Rheum ribes with ZnO nanoparticle and its antidiabetic, antibacterial, DNA damage prevention and lipid peroxidation prevention activity of in vitro' [Environ. Res. 204 (2022) 112363

Green synthesis of metal oxide nanoparticles using plant extracts offers an eco-friendly and sustainable approach for developing effective photocatalysts for environmental remediation. The present study reports the green synthesis of zinc oxide nanoparticles (ZnO NPs) using aqueous fruit extract of Manilkara zapota as a reducing and stabilising agent, with zinc nitrate as the precursor salt. The synthesised nanoparticles were characterised using Fourier Transform Infrared Spectroscopy (FT-IR), Field Emission Scanning Electron Microscopy (FESEM), Energy Dispersive X-ray Analysis (EDX), and X-ray Diffraction (XRD). FT-IR analysis revealed the presence of hydroxyl, amine, carbonyl, and alkyl functional groups involved in nanoparticle formation and stabilisation. FESEM micrographs showed predominantly spherical nanoparticles with slight agglomeration and an average particle size of approximately 35 nm. EDX analysis confirmed the elemental composition of zinc and oxygen, while XRD patterns verified the crystalline wurtzite structure of ZnO with an average crystallite size of 26.99 nm. The antioxidant potential of the nanoparticles was evaluated using the DPPH free radical scavenging assay and demonstrated appreciable antioxidant activity. Furthermore, the photocatalytic performance of the ZnO nanoparticles was assessed using methylene blue dye as a model pollutant under xenon lamp irradiation. The nanoparticles exhibited significant dye degradation efficiency, with degradation increasing progressively with irradiation time. The enhanced photocatalytic activity was attributed to the nanoscale size, high surface area, and abundance of active catalytic sites. The study demonstrates that Manilkara zapota-mediated ZnO nanoparticles are environmentally friendly, cost-effective, and promising materials for wastewater treatment and environmental remediation applications.

Antimony (Sb) is a toxic metalloid that poses a significant threat to living organisms and ecosystem sustainability. Biochar (BC) and zinc oxide nano-particles (ZnO-NPs) are promising amendments to mitigate heavy metals toxicity. However, the potential role of BC and ZnO-NPs in alleviating the Sb toxicity remains unexamined. To address this gap, the present study investigated how BC and ZnO-NPs mitigate Sb toxicity in rice. The study included eight different treatments: control, biochar (2%), ZnO-NPs (100 mg L- 1), BC + ZnO-NPs, Sb stress (250 mg kg- 1), Sb stress + BC (2%), Sb stress + ZnO-NPs, and Sb stress + BC (2%) + ZnO-NPs. Antimony suppressed rice growth and yield by inducing oxidative stress (increased hydrogen peroxide (H2O2) and electrolyte leakage), enhancing soil Sb availability and its accumulation in plant tissues, while reducing hormones synthesis and soil nutrients availability. Biochar + ZnO-NPs markedly enhanced the rice yield by decreasing H2O2 synthesis (26.06%), EL production (25.68%), soil Sb availability (41.80%) and increasing antioxidants activities, formation of iron plaque in roots (63.60%) and soil nutrients availability. Additionally, BC + ZnO-NPs upregulated the antioxidant genes (OsAPx6, OsCAT, OsPOD, and OsSOD), and downregulated the expression of OsSMP and OsMTP1 genes associated with Sb transport, thus helping to counteract Sb toxicity. These findings suggest that the BC + ZnO-NPs can effectively mitigate the Sb toxicity and improve rice productivity. These findings provide insights to develop the measure for remediating Sb-polluted soils, while simultaneously increasing the safe and sustainable crop production.

This study explores the performance, combustion, and emission parameters of a neem biodiesel enhanced with zinc oxide (ZnO) Nanoparticles (NPs) synthesized through a green method in a compression ignition (CI) engine. Neem oil was transesterified to produce biodiesel, while ZnO NPs were synthesized using neem leaf extract and dispersed at concentrations of 50 ppm and 100 ppm, denoted as NB25Zn50 and NB25Zn100, respectively. The outcomes showed that the addition of ZnO NPs significantly enhanced combustion efficiency, resulting in Brake Thermal Efficiency (BTE) increases of 1.51% for NB25Zn50 and 3.64% for NB25Zn100, along with Specific Fuel Consumption (SFC) decreases of 2.54% and 5.28%, respectively. Combustion analysis revealed a higher peak cylinder pressure (CP), increased Heat Release Rate (HRR), and quicker Mass Fraction Burning (MFB) progression for fuels blended with NPs, indicating a shorter Ignition Delay (ID) and more complete combustion. Emission analysis showed considerable reductions in Carbon monoxide (CO), Hydrocarbons (HC), and smoke opacity, whereas the optimal ZnO concentration (100 ppm) effectively controlled Nitrogen Oxides (NOx) emissions. Additionally, machine learning models such as K-Nearest Neighbors (KNN), Rrandom Forest (RF), Ssupport Vector Regression (SVR), and Extreme Gradient Boosting (XGB) were used to predict engine performance, emissions, and energy parameters. Among these, extreme gradient boosting demonstrated superior predictive accuracy with high correlation coefficients (R ≈ 0.99) and minimal error. Overall, neem biodiesel blended with ZnO NPs, especially at 100 ppm, exhibited strong potential as a sustainable fuel for enhanced overall engine performance and cleaner emissions.

The role of biosynthesized zinc oxide nanoparticles in modulating the expression of virulence factors in multidrug-resistant Klebsiellapneumoniae.

A novel electrochemical sensing with MIP for highly selective and sensitive determination of anticancer drug erlotinib.

The rising prevalence of multidrug-resistant (MDR) pathogens necessitates the development of sustainable, biocompatible antimicrobial agents. Green synthesis of metal oxide nanoparticles using endophytic microorganisms offers an eco-friendly and bioactive alternative to conventional physical and chemical methods. In this study, zinc oxide nanoparticles (ZnO NPs) were biosynthesized using the cell-free supernatant of Streptomyces werraensis, a novel endophytic actinobacterium isolated from the medicinal plant Passiflora caerulea L. The formation of ZnO NPs was monitored via UV–visible spectroscopy and Fourier Transform Infrared (FTIR) spectroscopy. Morphological and structural characterizations were performed using Transmission Electron Microscopy (TEM), Selected Area Electron Diffraction (SAED), and Dynamic Light Scattering (DLS). The biological potential of ZnO NPs for human health was evaluated through antibacterial assays against a panel of human pathogens and antioxidant assays (DPPH and ABTS). UV–Vis spectra confirmed ZnONP formation with a characteristic band-gap absorption, while FTIR identified proteinaceous and phenolic capping agents. TEM and SAED revealed highly crystalline, predominantly spherical nanoparticles with an average diameter of 136 nm and a wurtzite crystal structure. The biosynthesized ZnO NPs exhibited potent, concentration-dependent antibacterial activity, particularly against Gram-negative strains; Salmonella paratyphi A and Proteus vulgaris showed maximum inhibition zones of 19.0 ± 0.64 mm and 16.4 ± 0.68 mm, respectively, which are comparable to those of commercial ampicillin. Antioxidant assays demonstrated significant radical-scavenging potential, with an IC50 of 22.15 ± 1.2 µg/mL in the ABTS assay, approaching that of ascorbic acid. The findings of the present study demonstrate that S. werraensis-mediated ZnO NPs serve as effective “nanogenerators” of oxidative stress, offering a dual-action therapeutic approach. These results highlight the potential of endophytic actinobacteria as sustainable bio-factories for producing functional nanoparticles with promising antimicrobial potential for treating MDR infections.Supplementary InformationThe online version contains supplementary material available at 10.1038/s41598-026-54975-2.

Herein, the microwave method of synthesising ZnO/pectin and ZnO/polyethelene glycol nanohybrid composites using Clitoria ternate flower extract has been synthesised and evaluated by spectral and biological methods. The spectral characterization of ZnO nanoparticles and their composites was performed using FTIR, XRD, TGA, UV, SEM-EDX, and TEM, whereas biological evaluation was performed using antimicrobial, antibiofilm, and antioxidant studies. The potential cytotoxicity against the HT-29 human colorectal adenocarcinoma cell line showed an inhibitory concentration (IC50) of 22.7 ± 0.05 µg/mL. ZnO nanoparticles and polymer nanocomposites synthesized via green microwave processing with C. ternatea extract exhibited strong antibacterial activity, with inhibition zones of 11–22 mm for E. coli and 6–19 mm for S. aureus (ZnO/pectin showed superior efficacy). Similar trends were observed in antibiofilm, antioxidant, antifungal, and anticancer assays, with ZnO/pectin achieving an IC50 of 22.7 ± 0.05 µg/mL against HT-29 cells.

Synthesis and multipurpose efficacy of novel PrxSmyZn1-x-yO nanoparticles: Antibacterial, cytotoxic and photocatalytic activities.

Infections are the most frequent complication that impair normal skin repair, often leading to chronic wounds. To overcome this challenge, zinc oxide nanoparticles (ZnO NPs) were synthesized via green combustion using Moringa oleifera extract as fuel. These nanoparticles were incorporated into a poly(caprolactone)/poly(ethylene oxide) (PCL/PEO) membrane fabricated via electrospinning. The composite membranes were characterized by water contact angle, fluid absorption, morphology (SEM), cytotoxicity, cell proliferation (scratch assay), and antibacterial activity against Staphylococcus aureus and Escherichia coli. The PCL/PEO membrane containing 5% ZnO exhibited optimal characteristics, including hydrophilicity, water uptake capacity exceeding 300%, and a morphology that is suitable for wound healing applications, with an average fiber diameter of 2.93 ± 2.05 µm, pore size of 21.46 ± 8.19 µm, and porosity exceeding 75%. Additionally, the membrane demonstrated excellent biocompatibility with murine fibroblasts, achieving a cell viability of 100%, and exhibited antibacterial activity against Staphylococcus aureus and Escherichia coli, with inhibition zones of 2.0 and 1.0 mm, respectively. The green synthesized moringa‐ZnO imparted outstanding properties to the electrospun membrane, making the system PCL/PEO/moringa‐ZnO a promising candidate for advanced wound dressings capable of promoting accelerated wound closure and treating infected wounds.

Restoring BECN1-mediated autophagy mitigates acute lung injury caused by zinc oxide nanoparticles.

Salt stress is an abiotic stressor that adversely affects the growth and productivity of caraway, an important aromatic plant. A randomized complete split-plot design was used to determine the nanoparticles of zinc oxide (ZnO NPs) effects at levels of 0, 0.2, and 0.4 g L-1 on fruit yield, chemical and biochemical composition, and essential oil (EO) productivity of caraway plants subjected to saline irrigation water containing 0, 1, 2, 3, and 4 g L-1 sodium chloride (NaCl). The results indicated that increasing NaCl concentrations significantly reduced yield traits, relative water content, salinity tolerance index, leaf pigment concentrations, N, P, K, and Zn concentrations, fruits’ total proteins and total carbohydrates and percentage and yield/plant of essential oil (EO) in comparison to the untreated plants. Conversely, proline content, Na% and Cl%, and the activities of catalase, peroxidase, superoxide dismutase, and polyphenol oxidase increased with increasing NaCl concentrations relative to the control. Foliar application of ZnO NPs significantly increased the parameters relative to the untreated control except proline content, Na%, and Cl%, which were in comparison to respective control significantly reduced. Moreover, utilization of ZnO NPs positively affected the traits mentioned above under all NaCl concentrations tested compared to treatments without ZnO NPs. Different combinations of NaCl and ZnO NPs concentrations had varying effects on EO composition. A total of 32 compounds were identified across all treatment combinations, with the highest number (14) observed in the control. The major EO compounds were carvone (up to 49.71%) in the 2 g L-1 NaCl + 0.2 g L-1 ZnO NPs treatment, limonene (up to 28.68%) in the 2 g L-1 NaCl + 0.4 g L-1 ZnO NPs treatment, and D-limonene (up to 25.95%) in the 4 g L-1 NaCl + 0 g L-1 ZnO NPs treatment. These results suggest that the application of ZnO NPs may provide a sustainable approach to caraway cultivation under saline conditions.