Antimicrobial photodynamic therapy is one of the effective strategies for facing the resistance of pathogenic microorganisms of traditional antibiotics. In connection with this, new effective compounds are being sought, increasing their biological activity upon irradiation. In this work, a new polypropylene imine (PPI) from the first generation was synthesized and modified with 1,8-naphthalimide, to which a sulfonyl chloride group (D1) was introduced at the C-4 atom, from which after interaction with glucosamine, a dendrimer containing a sulphonamide group (D2) was obtained. The photophysical characteristics of dendrimer D2 were investigated in five organic solvents of different polarity and aqueous media. It was found that the absorption and fluorescence maxima are slightly affected by the polarity of the solvents. Excimer and monomeric fluorescence were also recorded with dendrimer D2 in an aqueous solution. Dendrimer D2 was deposited on the surface of the cotton fabric, and its release from the cotton fabric was studied for 4 h in a phosphate buffer at 37 °C. The antimicrobial activity of dendrimer D2 was investigated in meat-peptone broth (MPB) against Gram-positive B. cereus and Gram-negative P. aeruginosa and on cotton fabric compared in the dark and after irradiation with sunlight. It has been found that after irradiation with light, the activity of D2 and cotton fabrics is enhanced due to their antimicrobial photodynamic activity. Additionally, light can be utilized to self-sterilize cotton fabrics when treated with D2. 

Fish trypanosomiasis is a common blood parasitic disease transmitted by aquatic invertebrates, such as leeches. This study
aims to shed light on the cytotoxicity of Trypanosoma sp. on erythrocytes and its impacts on the innate immune response
(serum lysozyme activity, nitric oxide production, phagocytic activity, serum total protein, and globulin) in wild African
catfish, Clarias gariepinus. One hundred catfish were examined using blood smears stained with Giemsa and confirmed with
PCR. The prevalence of infection was found to be 10% by microscope detection and 15% by PCR. The morphological identification
of Trypanosoma as Trypanosoma mukasai was determined. Additionally, this study included previously undescribed
features of Trypanosoma, such as the width of the anterior and posterior body, the length of the posterior pale region, and
the number of folds. Various alterations in erythrocytes were observed, totaling 54.57%. Nuclear abnormalities, including
fragmented nuclei, eccentric nuclei, and micronuclei, were also reported. Infected fish showed a reduction in serum total
protein and globulin levels, while nitric oxide production, lysozyme activity, and phagocytic activity exhibited a significant
increase compared to non-infected fish. We believe that our findings will contribute valuable data to the morphological and
molecular identification of Trypanosoma sp. in African catfish, as well as their cytotoxic impact.

Water pollution has emerged as a major challenge for the scientific community because of the rapid expansion of the population and the industrial sector in the world. The current study focuses on introducing a new track for designing new optical nanocomposites for purifying water in addition to providing a new additive for building new nanohybrids. These targets were achieved through building a ternary system of Co/Ti/Zn nanocomposites and nanolayered structures. The Co/Ti/Zn nanolayered structures were prepared and intercalated by different kinds of organic acids: monocarboxylic and dicarboxylic acids. Long chains of organic acids were used to construct series of organic–inorganic nanohybrids. X-ray diffraction, thermal analyses, Fourier Transform Infrared spectroscopy, and scanning electron microscopy confirmed the formation of nanolayered structures and nanohybrids. The optical properties of the nanolayered structure showed that the Co/Ti/Zn LDH became photo-active compared with the usual Al/Zn LDH because of the reduction in the band gap energy from 5.3 eV to 3.3 eV. After thermal treatment, a highly photo-active nanocomposite was produced through observing more reduction for the band gap energy to become 2.8 eV. In addition, the dye of Acid Green 1 completely decomposed and converted to water and carbon dioxide during 17 min of UV radiation by the dual Co/Ti-doped zinc oxide nanocomposite. In addition, the kinetic study confirmed that the high optical activity of the dual Co/Ti-doped zinc oxide nanocomposite accelerated the degradation of the green dyes. Finally, from these results it could be concluded that designing effective nanocomposite for purification of water was accomplished through converting 2D nanolayered structures to a 3D porous structure of Ni/Ti/Zn nanocomposites. In addition, a new additive was achieved for heterostructured hybrids through building new Co/Ti/Zn/organic nanohybrids

ZnO nanoparticles (NPs) were prepared by green synthesis using plant leaf extraction of Ochradenus baccatus and characterized by XRD, FESEM, HRTEM, and Raman spectroscopy techniques. Since elevated CO levels have been associated with inflammatory conditions, cardiovascular diseases, and respiratory disorders and the methane gas primarily produced by gut microbiota and linked to gastrointestinal disorders and other abnormal methane levels in breath samples, the nanoparticles were applied for gas sensor fabrication. Thus, the gas sensors fabricated using ZnO nanoparticles were investigated for CH4 , H2 , CO, and NO2 gases. The gas sensing was performed for the fabricated sensors at various operating temperatures and gas concentrations. Interestingly, leaf-extracted green synthesized ZnO NPs were more sensitive to CH4 , CO, and NO2 gases than to H2 . The results of sensing studies revealed that the nanoparticles exhibit a selectivity toward gas depending on the gas type. The sensor response was also studied against the humidity. These findings bridge between the laboratory and industry sectors for future gas sensors development, which can be used for exhaled breath analysis and serve as potential diagnostic tools for highly sensitive contagious diseases.

Water pollution is one of the main challenges currently facing scientists around the world because of the rapid growth in industrial activities. On this basis, 2D nanolayered and nanohybrid structures, which are based on a ternary system of nickel–titanium–zinc, are considered favorable sources for designing effective nanocomposites for the photocatalytic degradation of industrial pollutants in a short period of time. These nanocomposites were designed by modifying twodimensional nanolayers to produce a three-dimensional porous structure of multi-doped Ni/Ti-ZnO nanocomposites. Additionally, another additive was produced by constructing nanohybrids of nickel– titanium–zinc combined with a series of hydrocarbons (n-capric acid, myristic acid, stearic acid, suberic acid, and sebacic acid). Energy-dispersive X-ray spectrometry, X-ray diffraction, scanning electron microscopy, infrared spectroscopy, and thermal analyses confirmed the growth of the nanolayered and nanohybrid materials in addition to the production of nanocomposites. The positive role of the dopants (nickel and titanium) in producing an effective photocatalyst was observed through a significant narrowing of the band gap of zinc oxide to 3.05–3.10 eV. Additionally, the high photocatalytic activity of this nanocomposite enabled the complete removal of colored dye from water after 25 min of UV radiation. In conclusion, this study proposes an unconventional approach for designing new optical nanocomposites for purifying water. Additionally, it suggests a novel supporting method for designing new kinds of nanohybrids based on multi-metals and organic acids.

We report an economical approach for the fabrication of laser-produced graphene (LPG) electrodes, which results in an improved electrochemical performance. Polyimide polymer was used as the starting material for LPG synthesis and was irradiated under ambient conditions with a CO2 laser. The prepared LPG samples were characterized by Raman spectroscopy and FTIR, which validated the formation of multilayer graphene containing sp2 hybridized C＝C bonds. FE-SEM revealed three-dimensional (3D) sheet-like structures, while HR-TEM images showed lattice planes with an interplanar spacing of approximately 0.33 nm, corresponding to the (002) plane of graphene. Their electrochemical performance showed a remarkable areal specific capacitance (CA) of 51 mF cm−2 (170 F g−1) at 1 mA cm−2 (3.3 A g−1) in a three-electrode configuration with 1 mol L−1 KOH as the aqueous electrolyte. The LPG electrodes produced an energy density of ~3.5 µWh cm−2 and a power density of ~350 µW cm−2, demonstrating significant energy storage ability. They also had an excellent cycling stability, retaining 87% of their specific capacitance after 3 000 cycles at 1 mA/cm2. A symmetric supercapacitor fabricated with LPG electrodes and the 1 mol L−1 KOH electrolyte had a specific capacitance of 23 mF cm−2 and showed excellent retention after 10 000 cycles, showing LPG’s potential for use in supercapacitors. Key words: Supercapacitors; Graphene; LPG; Electrochemical studies; Charge storage mechanism

This study reports the use of tin oxide (SnO2) octahedral nanoparticles with exposed high-energy facets as sensing material in inkjet-printed carbon monoxide (CO) gas sensors. The nanoparticles were synthesized via a hydrothermal method aimed at encouraging high-indexed (221) crystal planes to be exposed as facets, since their high surface energy may encourage interactions with gases. Studies by X-ray diffraction (XRD) confirmed the identity of the SnO2, while transmission electron microscopy (TEM) revealed formations of octahedral-shaped SnO2 nanoparticles, with features confirming the exposure of high-energy (221) crystal facets. The nanoparticles’ reductive behavior in a CO environment was studied using temperature-programmed reduction (TPR). A stable ink based on the SnO2 nanoparticles was successfully prepared and utilized to fabricate, via inkjet printing, homogenous films onto electrically conductive graphene-based interdigitated electrodes. Optimizing the inkjet printing parameters enhanced the CO gas sensing performance of the fabricated sensors. For example, at 200 ppm, the sensor with 10 printed layers recorded a sensitivity of about 20%, as compared to a sensitivity of not more than 14% recorded in each of the sensors with 5, 15, and 20 printed layers. As a result of having homogenous films, the inkjet-printed sensors also exhibited almost double the sensitivity of similar sensors prepared by drop-casting method.

Tannery wastewater is a major environmental pollutant that introduces toxic compounds, including chromium (Cr), into agricultural soils, posing significant challenges to plant growth and productivity. This research uniquely evaluates the efficacy of three specific plant growth-promoting rhizobacteria (PGPR)—Paenibacillus polymyxa, Bacillus amyloliquefaciens, and Pseudomonas putida—for mitigating Cr stress in rice (Oryza sativa L.). In this study, O. sativa plants were exposed to different levels of tannery wastewater (0%, 50%, and 100%) in a controlled pot experiment to assess the impact of P. polymyxa, B. amyloliquefaciens and P. putida on various morpho-physio-biochemical traits. Results from the present study revealed that the Cr toxicity induced a substantial decrease in shoot length, root length, number of leaves, leaf area, shoot fresh weight, root fresh weight, shoot dry weight, root dry weight, chlorophyll-a, chlorophyll-b, total chlorophyll, carotenoid content, net photosynthesis, stomatal conductance, transpiration rate, soluble sugar, reducing sugar, non-reducing sugar contents, calcium (Ca²⁺), magnesium (Mg²⁺), iron (Fe²⁺), and phosphorus (P) contents in the plants. However, Cr stress also induced oxidative stress in the plants by increasing malondialdehyde (MDA) and hydrogen peroxide (H₂O₂), which also led to an increase in various enzymatic and nonenzymatic antioxidants and also the gene expression and sugar content. Furthermore, a significant (P < 0.05) increase in proline metabolism, the AsA–GSH cycle, and the pigmentation of cellular components was observed. Addition of P. polymyxa, B. amyloliquefaciens and P. putide into the soil significantly alleviated Cr toxicity effects on O. sativa by improving photosynthetic capacity and ultimately plant growth. Increased activities of antioxidant enzymes in organic acid and PGPRs-treated plants seem to play a role in capturing stress-induced reactive oxygen species as was evident from lower levels of MDA and H₂O₂. Moreover, the application of different PGPRs enhanced both the abundance and diversity of the rhizosphere microbiome, with bacterial population levels and Shannon diversity indices significantly increasing. A marked reduction in daily Cr intake and associated health risks was also observed under these treatments, and proteomic responses under Cr stress. Research findings, therefore, suggested that the application of PGPRs can ameliorate Cr toxicity in O. sativa seedlings and resulted in improved plant growth and composition under metal stress.