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Biosynthesis techniques for nanomaterials have advanced significantly, promoting eco-friendly synthesis chemistry as a sustainable alternative to conventional methods. This study presents a novel and environmentally friendly approach for synthesizing nanoparticulate ZnO, CuO, and ZnO/CuO nanocomposites using aqueous extracts of Pleurotus ostreatus spent substrate, is reported. The structural, optical, and morphological properties of the synthesized NPs were analysed. A hexagonal phase of ZnO NPs and a monoclinic phase of CuO NPs were obtained according to the X-ray diffraction analysis. A reduction in the peak intensity of these metal oxides was observed in the ZnO/CuO NPs due to reduced crystallinity. The absorption spectra, obtained from the UV-vis analysis, showed peaks at 354, 365, and 525 nm for the ZnO, CuO, and ZnO/CuO NPs, respectively. An anticancer assay of the NPs was conducted using human embryonic kidney (HEK 293) and cervical carcinoma (HeLa) cell lines, while a 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay was used for the antioxidant evaluation. The ZnO, CuO, and ZnO/CuO NPs showed higher antioxidant potency with IC 50 of 2.15, 2.16, and 3.18 µg/mL, respectively, than the ascorbic acid (4.25 µg/mL). This indicates that the nanoparticles were more effective in capturing DPPH free radicals. Anticancer assays showed strong cytotoxic effects for all nanoparticles, with ZnO NPs exhibiting the highest activity (IC 50 : 1.94 μM for HEK 293 cells, 3.23 μM for HeLa cells), surpassing CuO and ZnO/CuO NPs. Cell viability for both HEK 293 and HeLa cells decreased as nanoparticle concentration increased, confirming dose-dependent cytotoxicity. The green synthesized metal oxides and their composite have the potential for biomedical applications., Competing Interests: Declarations. Ethical approval: Not applicable. Consent for publication: All authors are aware of this submission. Competing interests: The authors declare no competing interests., (© 2025. The Author(s).)

The release of common medications and illegal drugs into the environment could be potentially harmful to the ecosystem and hamper the behavior and growth of plants and animals. These pollutants gain access to water through sewage and factory discharges and have been found to exceed safety limits in water bodies. Therefore, there is an urgent need for improved wastewater purification systems. In this study, semiconductor-based heterojunction photocatalyst CuInS 2 /CeO 2 , synthesized through a facile solvothermal process, was explored for the photocatalytic degradation of ciprofloxacin, commonly used antibiotics. Studies on the electronic properties of the heterojunction revealed interfacial characteristics that were suitable for enhanced charge carrier separation and transport and a potential S-scheme charge transfer mechanism. The heterojunction achieved ∼90% efficiency for the degradation of CIP compared to 60% and 12% reported for CeO 2 and CuInS 2 , respectively. This shows an improvement in the activity, which results from the improved charge carrier properties of the heterojunction. Further investigation of the charge transfer mechanism through radical scavenging experiments identified • OH, O2 •- , and h + as active species contributing to the catalyst's efficacy. Based on X-ray photoelectron spectroscopy analysis, a proposed S-scheme charge transfer mechanism was suggested for the CuInS 2 /CeO 2 heterojunction. The findings indicate the potential of the CuInS 2 /CeO 2 heterojunction as a promising photocatalyst for treating waste effluents from the pharmaceutical industry.

Hybrid wastewater treatment systems offer viable solutions to enhance the removal of complicated contaminants from aqueous system. This innovation has opened new avenues for advanced wastewater treatment processes. Herein, a novel TiO 2 -ZnO functionalized coal fly ash-based ceramic membrane was fabricated by utilizing a combined pressing and sintering method. The intrinsic properties of the functionalized membranes were characterized and their chemical and physical properties such as chemical stability, mechanical stability, water absorption, and porosity were established. The shape, crystallinity, thermal characteristics, and functional groups present were also determined using SEM, XRD, TGA, and FTIR studies, respectively. The results showed that the ceramic membrane functionalized with 0.5 g of TiO 2 -ZnO and sintered at 850 °C exhibited the best thermal, and chemical stability, and possessed the required porosity for ultrafiltration applications. Photocatalytic degradation of tetracycline (TC) as a model pollutant was examined and the optimum efficiency of 77% was achieved within 100 min of visible irradiation using the functionalized membrane. Moreso, the functionalized membrane was found to be stable with 73% degradation efficiency after 5 consecutive cycles of reusability study, showing negligible loss of efficiency. The scale-up of photocatalytic ceramic membranes and their utilization in real industrial applications will confirm their robustness., Competing Interests: Declarations. Competing interests: The authors declare no competing interests., (© 2024. The Author(s).)

Feedlot finishing of beef cattle on commercial nutrient-dense diets based on expensive corn (maize), soybean meal (SBM) and other commonly used protein-rich ingredients is economically unsustainable, especially for smallholder farmers. Rich in energy and proteins, Mucuna pruriens utilis seed meal (MSM) could replace corn and protein-rich ingredients in beef cattle diets provided its problems of antinutritional factors (ANFs) and high fiber content that compromise animal growth performance are resolved. The objective of this study was, therefore, to investigate the effects of incorporation of conventional (C-Nano-ZnO) versus green (G-Nano-ZnO) zinc oxide (ZnO) nanoparticles in the diets of feedlot-finished Bonsmara steers supplemented with 20% MSM (dry matter basis). In a completely randomized design, 28 Bonsmara steers were randomly allocated to 4 experimental diets [i.e., Control diet without MSM (C); C with 20% MSM replacing corn (partially) and the common protein-rich ingredients (CM); CM with 25 mg/kg C-Nano-ZnO (CM-C); and CM with 25 mg/kg G-Nano-ZnO (CM-G)] each with seven replicates for 98 days. Performance variables, carcass traits, hemato-biochemistry, and meat quality were then measured. All data were analyzed with SAS using one-way ANOVA applying the GLM procedure, with diet as the independent variable, except for growth performance data that were analyzed as repeated measures. Results showed that while dietary MSM did not affect (P > 0.05) meat quality and serum biochemistry, it decreased body weight gain (BWG; P < 0.01), feed intake (FI; P = 0.001), feed conversion efficiency (FCE; P < 0.01), carcass fatness (P = 0.05), hot carcass weight (HCW; P < 0.05), cold carcass weight (CCW; P = 0.05), blood MCV (P < 0.05), MCH (P < 0.01), and neutrophils (P < 0.01) as it increased blood lymphocytes (P < 0.001). Interestingly, the harmful effects of MSM were attenuated by C-Nano-ZnO and worsened by G-Nano-ZnO. In conclusion, feeding of high dietary unprocessed MSM did not affect Bonsmara beef meat quality and serum biochemistry but compromised their growth performance, carcass traits, and some hematology responses, and these were alleviated by C-Nano-ZnO and deteriorated by G-Nano-ZnO incorporation. We recommend feeding commercial diets supplemented with 20% MSM, replacing corn and commonly used protein-rich ingredients, plus 25 mg/kg of C-Nano-ZnO to feedlot-finishing beef cattle., Competing Interests: Declarations Ethical approval This study was performed following the ethical guidelines of North-West University (NWU) with approval by the NWU Animal Production Research Ethics Committee (Approval #: NWU-00804-22-A5) as well as the North West Department of Agriculture and Rural Development (Approval #: NWAE/23/05/03). Conflict of interest The authors declare no conflict of interest., (© 2024. The Author(s).)

Lead halide perovskite single crystals (LHPSC) are promising for room-temperature γ-ray spectroscopy in radiation detection. While MA(CH 3 NH 3 )-based LHPSCs are the most straightforward and cost-effective to synthesize from solution, their performance in γ-ray spectroscopy is hindered by significant noise and ion migration at high bias, which degrades their energy resolution (ER). The work introduced an n-type/intrinsic/n-type photodiode incorporating passivation layers of MA-based LHPSCs, grown through solution-process epitaxial growth. This single-polarity device demonstrated an outstanding ER of 3.6% for 662 keV γ-ray photons. Overall, this work provides useful information for developing room-temperature γ-ray detectors based on solution-processed lead halide perovskites.

The concept of this review underscores a significant shift towards sustainable agricultural practices, particularly from the view point of microbial biotechnology and nanotechnology. The global food insecurity that causes increasing ecological imbalances is exacerbating food insecurity, and this has necessitated eco-friendly agricultural innovations. The chemical fertilizers usage aims at boosting crop yields, but with negative environmental impact, thus pushing for alternatives. Microbial biotechnology and nanotechnology fields are gaining traction for their potential in sustainable agriculture. Endophytic fungi promise to synthesize nanoparticles (NPs) that can enhance crop productivity and contribute to ecosystem stability. Leveraging on endophytic fungi could be key to achieving food security goals. Endophytic fungi explore diverse mechanisms in enhancing plant growth and resilience to environmental stresses. The application of endophytic fungi in agricultural settings is profound with notable successes. Hence, adopting interdisciplinary research approaches by combining mycology, nanotechnology, agronomy, and environmental science can meaningfully serve as potential pathways and hurdles for the commercialization of these biotechnologies. Therefore, setting regulatory frameworks for endophytic nanomaterials use in agriculture, by considering their safety and environmental impact assessments will potentially provide future research directions in addressing the current constraints and unlock the potential of endophytic fungi in agriculture., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Co-author, Prof. Damian C. Onwudiwe is serving in an editorial capacity (Associate Editor) for the Heliyon and was not involved in the editorial review or the decision to publish this article. Therefore, the authors declare that they have no competing interests. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 Published by Elsevier Ltd.)

In this work, an efficient and robust hole transport layer (HTL) based on blended poly((9,9-dioctylfluorenyl-2,7-diyl)- alt -(9-(2-ethylhexyl)-carbazole-3,6-diyl)) (PF8Cz) and crosslinkable 3,3'-(9,9-dimethyl-9 H -fluorene-2,7-diyl)bis(9-(4-vinylphenyl)-9 H -carbazole) (FLCZ-V) is introduced for high-performance and stable blue quantum dot-based light-emitting diodes (QLEDs), wherein FLCZ-V can in situ-crosslink to a continuous network polymer after thermal treatment and the linear polymer PF8CZ becomes intertwined and imprisoned. As a result, the blended HTL shows a high hole mobility (1.27 × 10 -4 cm 2 V -1 s -1 ) and gradient HOMO levels (-5.4 eV of PF8CZ and -5.7 eV of FLCZ-V) that can facilitate hole injecting so as to ameliorate the charge balance and, at the same time, achieve better electron-blocking capability that can effectively attenuate HTL decomposition. Meanwhile, the crosslinked blended HTL showed excellent solvent resistance and a high surface energy of 40.34 mN/m, which is favorable to enhance wettability for the deposition of a follow-up layer and attain better interfacial contact. Based on the blended HTL, blue QLEDs were fabricated by both spin-coating and inkjet printing. For the spin-coated blue QLED, a remarkable enhancement of external quantum efficiency (EQE) of 15.5% was achieved. Also, the EQE of the inkjet-printed blue QLED reached 9.2%, which is thus far the best result for the inkjet-printed blue QLED.

The combination of sensing invisible ultraviolet photons and infrared radiation can significantly enhance target recognition by offsetting their own limit in a short sensing range and poor spatial resolution. However, the difference in their wavelength sets unique requirements for sensing materials and devices, which makes it hard to establish their implementation in a single detector. In this work, we present the design of a single detector with CH 3 NH 3 PbCl 3 (MAPbCl 3 ) for distinguishing ultraviolet and IR signals by switching its operating mode in the photo-/thermo-electric effect. The large optical band gap of ∼3.2 eV in MAPbCl 3 ensures the response toward an ultraviolet photon, while its efficient thermoelectric effect allows the sensing of an IR signal. As a result, the detector exhibits a specific detectivity of 4.5 × 10 12 Jones for 395 nm ultraviolet photons under 0 V, while under the working voltage of 2.5 V, it demonstrates a superior temperature coefficient of resistance of -3.7% K -1 , a specific detectivity of 4.8 × 10 8 Jones, and a limit of detection of 0.58 mW/cm 2 for 4 μm photons. The functionality of the switching response to ultraviolet or IR photons by working voltage allows background subtraction and enhances the target discrimination in the imaging.

Over the years, the release of potential radiological components around the oil exploration environment has increased with potential health implications.Yet; the mechanism and health associated assessment have remained fuzzy to most experimental scientists. The current study determines the activity concentration of radionuclides in sediments and the corresponding health risk assessments from the hydrocarbon exploration environment of the southern coastal area of Delta State, Nigeria. A Sodium-iodide NaI(Tl) detector, with a well-calibrated multichannel analyzer (MCA) to ensure efficiency and energy was utilized. A total of seventy-five sediment samples (Five sediment samples each per community) were collected from the southern coastal area of Delta State, Nigeria. The mean activity concentrations of 40 K, 238 U, and 232 Th of the sediment samples were 3361.48 ± 194.26 Bqkg -1 , 40.11 ± 16.17 Bqkg -1 , and 45.73 ± 19.27 Bqkg -1 respectively. The obtained mean values exceeded the world standard limit of 400 Bqkg -1 , 35 Bqkg -1 , and 30 Bqkg -1 respectively. Also, the computed mean radiological health hazard risk of radium equivalent activity (Raeq), representative level index (I yr ), external hazard index (Hex), internal hazard index (Hin), absorbed gamma dose rate ( D ), annual effective dose equivalent outdoor and indoor (AEDE) and lifetime cancer risk (ELCR) values are 363.94 ± 32.37 Bkgl -1 , 2.9657 Bkgl -1 , 0.9839, 1.0919, 175.82 nGyh -1 , 2.1556 mSvyr -1 , 0.8625 mSvyr -1 , and 7.5447 mSvyr -1 respectively. The values were found to be slightly higher than the world standard limit. Therefore, the residents that are using the sediments of the southern coastal area for the construction of buildings as well as dwelling in houses built with such sediments are exposed to these radiological materials. This may pose a radiological health risk concern. The obtained results will serve as radiation and radiological baseline data for sediments of the southern coastal area of Delta State, Nigeria., Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: The corresponding author is an Associate Editor for Heliyon Materials., (© 2024 The Authors.)

The continued increase in the global population has resulted in increased water demand for domestic, agricultural, and industrial purposes. These activities have led to the generation of high volumes of wastewater, which has an impact on water quality. Consequently, more practical solutions are needed to improve the current wastewater treatment systems. The use of improved ceramic membranes for wastewater treatment holds significant prospects for advancement in water treatment and sanitation. Hence, different studies have employed ceramic membranes in wastewater treatment and the search for low-cost and environmentally friendly starting materials has continued to engender research interests. This review focuses on the application of coal fly ash in membrane technology for wastewater treatment. The processes of membrane fabrication and the various limitations of the material. Several factors that influence the properties and performance of coal fly ash ceramic membranes in wastewater treatment are also presented. Some possible solutions to the limitations are also proposed, while cost analysis of coal fly ash-based membranes is explored to evaluate its potential for large-scale applications., Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests:Damian Onwudiwe reports administrative support was provided by 10.13039/501100005274North-West University - Mafikeng Campus. Damian Onwudiwe reports a relationship with Elsevier B.V. that includes: Editorial board membership. Not applicable has patent Not applicable pending to Not applicable. Editorial Board Member of Heliyon-Materials If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

Sensitive thermometry or thermography by responding to blackbody radiation is urgently desired in the intelligent information life, including scientific research, medical diagnosis, remote sensing, defense, etc. Even though thermography techniques based on infrared sensing have undergone unprecedented development, the poor compatibility with common optical components and the high diffraction limit impose an impediment to their integration into the established photonic integrated circuit or the realization of high-spatial-resolution and high-thermal-resolution imaging. In this work, we present a sensitive temperature-dependent visible photon detection in Bi-doped MAPbX 3 (X = Cl, Br, and I) and employ it for uncooled thermography. Systematic measurements reveal that the Bi dopant introduces trap states in MAPbX 3 , thermal energy facilitates the carriers jumping from trap states to the conduction band, while the vacancies of trap states ensure the sequential absorption of visible photons with energy less than the band gap. Subsequently, the change of response toward the visible photon is applied to construct the thermograph, and it possesses a specific sensitivity of 2.11% K -1 along temperature variation. As a result, our thermograph presents a temperature resolution of 0.21 nA K -1 , a high responsivity of 2.06 mA W -1 , and a high detectivity of 2.08 × 10 9 Jones at room temperature. Furthermore, remote thermal imaging is successfully achieved with our thermograph.

Fabrication of heterojunction and surface defective engineering, through the formation of oxygen vacancies, are among the various photocatalytic enhancement techniques. A combination of these techniques has the prospect of enhancing photocatalytic activities through improved light absorption capabilities and charge separation process of the photocatalysts. In this study, a heterojunction of black titanium oxide-zinc oxide (BTiO 2 -ZnO) nanocomposite was synthesized using the conventional sol-gel approach, coupled with aluminum foil-assisted NaBH 4 reduction. The structure, morphology, surface properties, and optical characteristics of the synthesized material were studied using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), UV-vis absorption spectra, scanning electron microscope (SEM), Energy-dispersive X-ray spectroscopy (EDS), and transmission electron microscope (TEM). The XRD confirmed the successful formation of BTiO 2 -ZnO heterostructure, while SEM revealed the structural morphology as pseudo-spherical with slight agglomeration. BTiO 2 -ZnO was found to be more efficient than BTiO 2 and BZnO for the removal of tetracycline with degradation efficiencies of 63, 58, and 56 % respectively. The effects of process parameters such as the amount of photocatalyst, pollutant's concentration, and the initial solution pH on photocatalytic degradation study were systematically explored. The results confirm that the formation of the heterostructure from BTiO 2 and BZnO could offer a facile route to improving the catalytic degradation of tetracycline. Therefore, this study offers a novel perspective on the design of efficient metal oxide photocatalyst systems that rely on the integration of defect engineering and heterojunction for the removal of organic contaminants., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Authors.)

The halide lead perovskite single crystals (HLPSCs) have great potential in gamma-ray detection with high attenuation coefficient, strong defects tolerance, and large mobility-lifetime product. However, mobile halide ions would migrate under high external bias, which would both weaken the gamma-ray response and cause additional noise. Here, we report the gamma-ray PIN photodiodes made of cascade HLPSCs including both ion-formed and electron-hole-formed electrical junctions that could suppress the ions migration and improve the charges collection. Our photodiodes based on cascade HLPSCs (MAPbBr 3 /MAPbBr 2.5 Cl 0.5 /MAPbCl 3 ) show a wide halide-ion-formed depletion layer of ∼52 μm. The built-in potential along the wide ionic-formed junction ensures a high mobility-lifetime product of 1.1 × 10 -2 cm 2 V -1 . As a result, our gamma-ray PIN photodiodes exhibit compelling response to 241 Am, 137 Cs, and 60 Co; the energy resolution can reach 9.4%@59.5keV and 5.9%@662keV, respectively. This work provides a new path toward constructing high-performance gamma-ray detectors based on HLPSCs., Competing Interests: The authors declare no competing interests., (© 2023 The Author(s).)

Aflatoxin B1 is a secondary metabolite with a potentially devastating effect in causing liver damage in broiler chickens, and this is mainly facilitated through the generation of oxidative stress and malonaldehyde build-up. In the past few years, significant progress has been made in controlling the invasion of aflatoxins. Phytochemicals are some of the commonly used molecules endowed with potential therapeutic effects to ameliorate aflatoxin, by inhibiting the production of reactive oxygen species and enhancing intracellular antioxidant enzymes. Experimental models involving cell cultures and broiler chickens exposed to aflatoxin or contaminated diet have been used to investigate the ameliorative effects of phytochemicals against aflatoxin toxicity. Electronic databases such as PubMed, Science Direct, and Google Scholar were used to identify relevant data sources. The retrieved information reported on the link between aflatoxin B1-included cytotoxicity and the ameliorative potential/role of phytochemicals in chickens. Importantly, retrieved data showed that phytochemicals may potentially protect against aflatoxin B1-induced cytotoxicity by ameliorating oxidative stress and enhancing intracellular antioxidants. Preclinical data indicate that activation of nuclear factor erythroid 2-related factor 2 (Nrf2), together with its downstream antioxidant genes, may be a potential therapeutic mechanism by which phytochemicals neutralize oxidative stress. This highlights the need for more research to determine whether phytochemicals can be considered a useful therapeutic intervention in controlling mycotoxins to improve broiler health and productivity.

Zinc oxide (ZnO) and silver-zinc oxide (Ag/ZnO) nanocomposite were synthesized by a green method using Zn(CH 3 COO) 2 and AgNO 3 as precursors for zinc and silver respectively; and Urginea epigea bulb extract as a reducing/capping agent. The nanomaterials were characterized by X-ray diffraction (XRD) analysis, Fourier transform infrared spectrophotometer (FTIR), ultraviolet-visible spectrophotometer, scanning, and transmission electron microscopy (SEM and TEM). Their elemental composition was studied using EDX analysis, while elementary mapping was used to show the distribution of the constituent elements. The powder X-ray diffraction confirmed hexagonal phase ZnO, while the Ag/ZnO nanocomposites identified additional planes due to cubic phase Ag nanoparticles. The absorption spectrum of the nanocomposite indicated a red shifting of the absorption band of the metallic ZnO and a surface plasmon resonance (SPR) band's appearance in the visible region due to the metallic Ag nanoparticles. The analysis from the TEM image showed the particles were of spherical morphology with a mean size of 35 nm (ZnO) and 33.50 nm (Ag/ZnO). The biological activity of the nanoparticles was studied for their antibacterial and antioxidant capacity so as to assess their ability to hinder bacterial growth and capture radical species respectively. The results demonstrated that the modification of ZnO with silver nanoparticles enhanced the antibacterial potency but reduced the antioxidant activity. This biogenic method offers a facile approach to nanoparticles for biological purposes, and the strategy may be extended to other metal oxide and their composites with metallic silver nanoparticles as a more effective approach compared to the physical and chemical routes., Competing Interests: The authors declare no conflict of interest., (© 2022 The Author(s).)

The safety of water resources throughout the globe has been compromised by various human activities and climate change over the last decades. Consequently, the world is currently confronted with a severe shortage of water supply and a water safety crisis, amidst a growing population. With poor environmental regulations, indiscriminate budding of urban slums, poverty, and a lack of basic knowledge of hygiene and sanitation, the African water supply has been critically threatened by different organic and inorganic contaminants, which results in several health issues. Inorganic pollutants such as heavy metals are particularly of interest because they are mostly stable and non-biodegradable. Therefore, they are not easily removed from water. In different parts of the continent, the concentration of heavy metals in drinking water far exceeds the permissible level recommended by the World Health Organization (WHO). Worse still, this problem is expected to increase with growing population, industrialization, urbanization, and, of course, corruption of government and local officials. Most of the African population is ignorant of the standards of safe water. In addition, the populace lack access to affordable and reliable technologies and tools that could be used in the quantification of these pollutants. This problem is not only applicable to domestic, but also to commercial, communal, and industrial water sources. Hence, a global campaign has been launched to ensure constant assessment of the presence of these metals in the environment and to promote awareness of dangers associated with unsafe exposure to them. Various conventional spectroscopic heavy metal detection techniques have been used with great success across the world. However, such techniques suffer from some obvious setbacks, such as the cost of procurement and professionalism required to operate them, which have limited their applications. This paper, therefore, reviews the condition of African water sources, health implications of exposure to heavy metals, and the approaches explored by various indigenous electrochemists, to provide a fast, affordable, sensitive, selective, and stable electrochemical sensors for the quantification of the most significant heavy metals in our water bodies., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The green synthesis approach to nanoparticles has been widely received as an alternative to the conventional methods, specifically for applications in areas such as biology, agriculture and medicine, where toxicity is of great concern. In this study, copper oxide (CuO) and titanium oxide (TiO 2 ) nanoparticles (NPs) were synthesized using an aqueous extract of Mucuna pruriens utilis seed. The morphology and structural characterization of the NPs were achieved by using scanning and transmission electron microscopy (SEM and TEM), and X-ray diffraction (XRD) measurement, while the elemental composition was studied using electron diffraction X-ray spectroscopy (EDS). A monoclinic phase of CuO and anatase phases of TiO 2 with high crystallinity were confirmed from the diffraction patterns of the XRD. Both TEM and SEM micrographs of the CuO confirmed short rod-shaped nanostructure, while spherical morphologies were obtained for the TiO 2 NPs. The EDS study indicated that the composition of the samples conformed with the identified products in the XRD and attest to the purity of the NPs. The nanoparticles exhibited a dose-dependent profile in MTT cytotoxicity assay with some cell specificity. However, the anticancer potential of these NPs was still lower than that of the standard anticancer drug, 5-fluorouracil., Competing Interests: The authors declare no conflict of interest., (© 2022 The Author(s).)

Dual-mode photodetectors (PDs) have attracted increasing interest owing to their potential optoelectrical applications. However, the widespread use of PDs is still limited by the high cost of epitaxial semiconductors. In contrast, the solution processability and wide spectral tunability of perovskites have led to the development of various inexpensive and high-performance optoelectronic devices. In this study, we develop a high-performance electronically modulated dual-mode PD with near-infrared (NIR) narrowband and visible light broadband detection based on organic-inorganic hybrid methylammonium lead halide perovskite (MAPbX 3 ; MA = CH 3 NH 3 and X = Cl, Br, and I) single crystals with a pnp configuration. The operating mode of the dual-mode PD can be switched according to voltage bias polarity because the photon absorption region and carrier transport performance are tuned at different bias voltages. The dual-mode PD exhibits a NIR light responsivity of 0.244 A/W and a narrow full width at half-maximum of ∼12 nm at 820 nm at positive voltages and an average visible light responsivity of ∼0.13 A/W at negative voltages. The detectivities of both modes are high (∼10 12 Jones), and the linear dynamic range is wide (>100 dB). Our study provides a new method for fabricating multifunctional PDs and can expand their application in integrated imaging systems.

Biogenic metal oxide nanoparticles (NPs) have emerged as a useful tool in biology due to their biocompatibility properties with most biological systems. In this study, we report the synthesis of copper oxide (CuO), zinc oxide (ZnO) nanoparticles (NPs), and their nanocomposite (CuO-ZnO) prepared using the phytochemical extracts from the leaves of Dovyalis caffra (kei apple). The physicochemical properties of these nanomaterials were established using some characterization techniques including X-ray diffraction analysis (XRD), ultraviolet-visible spectroscopy (UV-vis), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy-dispersive X-ray spectroscopy (EDX). The XRD result confirmed the presence of a monoclinic CuO (Tenorite), and a hexagonal ZnO (Zincite) nanoparticles phase, which were both confirmed in the CuO-ZnO composite. The electron microscopy of the CuO-ZnO, CuO, and ZnO NPs showed a mixture of nano-scale sizes and spherical/short-rod morphologies, with some agglomeration. In the constituent's analysis (EDX), no unwanted peak was found, which showed the absence of impurities. Antioxidant properties of the nanoparticles was studied, which confirmed that CuO-ZnO nanocomposite exhibited better scavenging potential than the individual metal oxide nanoparticles (CuO, and ZnO), and ascorbic acid with respect to their minimum inhibitory concentration (IC 50 ) values. Similarly, the in vitro anticancer studies using MCF7 breast cancer cell lines indicated a concentration-dependent profile with the CuO-ZnO nanocomposite having the best activity over the respective metal oxides, but slightly lower than the standard 5-Fluorouracil drug.

In this study, chlorophenyltin(IV) [(C 6 H 5 )(Cl)Sn(L) 2 ] and diphenyltin(IV) [(C6H5)2Sn(L)2] of N -methyl- N -hydroxyethyldithiocarbamate were prepared and characterized using various spectroscopic methods (FTIR, 1 H, 13 C, and 119 Sn NMR) and elemental analysis. The FTIR and NMR spectral data, used to establish the structure of the compounds, showed the formation of the complexes via coordination to the two sulfur atoms from the dithiocarbamate ligand and the respective phenyltin(IV) derivatives. This coordination mode was further explored by DFT calculations, which showed that the bonding around the Sn center in [(C6H5)2Sn(L)2] was more asymmetric compared to the bonding around [(C 6 H 5 )(Cl)Sn(L) 2 ] . However, the Sn-S bonds in [(C 6 H 5 )(Cl)Sn(L) 2 ] were found to be more covalent than those in [(C6H5)2Sn(L)2] . Furthermore, the charge density of the frontier orbitals showed that the Sn atom in the complexes is relatively electrophilic and the Sn atom in [(C6H5)2Sn(L)2] has a lower atomic dipole moment than that of [(C 6 H 5 )(Cl)Sn(L) 2 ] . The cytotoxicity and anti-inflammatory study revealed that [(C6H5)2Sn(L)2] , with the higher number of phenyl substituents, has a higher potency than [(C 6 H 5 )(Cl)Sn(L) 2 ] . The bio-efficacy study of these complexes as cytotoxic and anti-inflammatory agents showed that the complexes possessed moderate to high activity in comparison to the camptothecin and diclofenac in each case. Nevertheless, the diphenyltin(IV) derivative [(C6H5)2Sn(L)2] was found to possess a better activity than its counterpart due to the number of phenyl rings attached to the Sn center.

The vastness of metal-based nanoparticles has continued to arouse much research interest, which has led to the extensive search and discovery of new materials with varying compositions, synthetic methods, and applications. Depending on applications, many synthetic methods have been used to prepare these materials, which have found applications in different areas, including biology. However, the prominent nature of the associated toxicity and environmental concerns involved in most of these conventional methods have limited their continuous usage due to the desire for more clean, reliable, eco-friendly, and biologically appropriate approaches. Plant-mediated synthetic approaches for metal nanoparticles have emerged to circumvent the often-associated disadvantages with the conventional synthetic routes, using bioresources that act as a scaffold by effectively reducing and stabilizing these materials, whilst making them biocompatible for biological cells. This capacity by plants to intrinsically utilize their organic processes to reorganize inorganic metal ions into nanoparticles has thus led to extensive studies into this area of biochemical synthesis and analysis. In this review, we examined the use of several plant extracts as a mediating agent for the synthesis of different metal-based nanoparticles (MNPs). Furthermore, the associated biological properties, which have been suggested to emanate from the influence of the diverse metabolites found in these plants, were also reviewed.

Dithiocarbamate ligands have the ability to form stable complexes with transition metals, and this chelating ability has been utilized in numerous applications. The complexes have also been used to synthesize other useful compounds. Here, the up-to-date applications of dithiocarbamate ligands and complexes are extensively discussed. Some of these are their use as enzyme inhibitor and treatment of HIV and other diseases. The application as anticancer, antimicrobial, medical imaging and anti-inflammatory agents is examined. Moreover, the application in the industry as vulcanization accelerator, froth flotation collector, antifouling, coatings, lubricant additives and sensors is discussed. The various ways in which they have been employed in synthesis of other compounds are highlighted. Finally, the agricultural uses and remediation of heavy metals via dithiocarbamate compounds are comprehensively discussed.

Background: A large volume of dye molecules finds its way into the environment, accumulates in water bodies, and makes the aquatic system unsafe to human health. Due to the complex nature of these dye materials, most of the conventional techniques are not effective for their removal. Semiconductor photocatalysis has emerged as a promising technique for  the destruction of organic pollutants under UV or visible light irradiation. Among the semiconductors, Bi 2 S 3 is widely employed in photocatalysis due to its non-toxicity and chemical stability. However, one of its problems is the high recombination rate of the charge, and various methods have been employed to enhance the photo-reactivity. One of  these methods is the incorporation of transition elements., Results: Herein, a facile solvothermal method was used to prepare Bi 2 S 3  nanorods and needle- shaped Sn doped Bi 2 S 3 , using bismuth(III) tris(N-phenyldithiocarbamate) as a single-source precursor. The prepared nanomaterials were characterized, and used as efficient photocatalyst for the photo enhanced degradation of methylene blue (MB) dye under visible light irradiation. The nanomaterials exhibited very good photocatalytic activity towards the photo degradation of MB, showing a degradation rate of up to 83% and 94% within 150 min for the pristine and Sn doped Bi 2 S 3 ,  respectively., Conclusion: The enhancement in the photocatalytic activity of the Sn doped Bi 2 S 3 was attributed to the suppression in the recombination rate of the electron-hole pairs, due to the formation of new energy level below the CB, that was capable of altering the equilibrium concentration of the carrier. This confirmed that Sn doped Bi 2 S 3 could be utilized as valuable cost-efficient catalysts for eliminating methyl blue from aqueous solutions and also possible candidates in environmental pollution treatment., (© 2021. The Author(s).)

In this work, CuO nanoparticles (NPs) were prepared from the aqueous extracts of Solanum macrocarpon fruit by using the conventional heating (CuO(h) NPs) and microwave irradiation (CuO(m) NPs) methods. The synthesized nanoparticles were characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray diffraction (XRD). The SEM analysis revealed that the CuO NPs from both routes contained essentially smooth surfaces, and displayed some degree of agglomeration. The TEM analysis confirmed some spherical morphology with mean particle sizes of 35.60 ± 6.24 nm and 47.14 ± 6.18 nm for the CuO(h) and CuO(m) NPs respectively. While the CuO(m) NPs possessed a single-phase consistent with the face cantered cubic structure of copper oxide, the CuO(h) NPs showed some extra peaks attributed to Cu 2 O NPs as secondary phase. Electrochemical studies were conducted in order to evaluate the electrochemical properties of the NPs. The responses of a gold screen-printed electrode surface treated with both NPs showed that their redox behaviours on (Fe(CN) 6 ) 3-/4- probe and KCl electrolytes vary significantly. In (Fe(CN) 6 ) 3-/4- probe, the SPAuE/CuO(h) showed enhanced electrochemical response relative to the bare, while the SPAuE/CuO(m) showed a lower current response than the bare. However, in the KCl electrolye, the SPAuE/CuO(h) and SPAuE/CuO(m) were highly electroactive and demonstrated peak current magnitude that was about 26.5 and 83.38 times higher than that of the bare. In this KCl medium, the magnitude of the oxidation peak current of Cu 2+ for SPAuE/CuO(m) was about 3 times higher than that of SPAuE/CuO(h). The percentage contraction in redox coordinates between the 1 st and 10 th scans in both electrodes were 3.88 and 19.28% for SPAuE/CuO(h) and SPAuE/CuO(m) respectively. Thus, the choice of green synthesis route could be exploited in different fields where green NPs is desired., Competing Interests: The authors declare no competing interests., (© 2020 The Author(s).)

Methyltin(IV) of butyltin(IV)- N -hydroxyethyl dithiocarbamate complexes, represented as [(CH 3 ) 2 Sn(L(OH)) 2 ] and [(C 4 H 9 ) 2 Sn(L(OH)) 2 ] respectively were synthesized and characterized using spectroscopic techniques ( 1 H, 13 C and 119 Sn NMR) and elemental analysis. Both infrared and NMR data showed that, the complexes were formed via two sulphur atoms of the dithiocarbamate group. This mode of coordination was further supported by the DFT calculation, which suggested the formation of a distorted octahedral geometry around the tin atom. The complexes were screened for their antioxidant, cytotoxicity and anti-inflammatory properties. Four different assays including DPPH, nitric oxide, reducing power and hydrogen peroxides were used for the antioxidant studies, while an in vitro anti-inflammatory study was done using albumin denaturation assay. The complexes showed good antioxidant activity, especially in the DPPH assay. Butyltin(IV)- N -hydroxyethyl dithiocarbamate showed better cytotoxicity activity compared to methyltin(IV)- N -hydroxyethyl dithiocarbamate in the selected cell lines, which included KMST-6, Caco-2 and A549 cell lines. The anti-inflammatory activities revealed that the two complexes have useful activities better than diclofenac used as control drug., Competing Interests: The authors declare no conflict of interest., (© 2021 The Author(s).)

Bi 2 S 3 and Sb 2 S 3 nanoparticles were prepared by microwave irradiation of single-source precursor complexes in the presence of ethylene glycol as a coordinating solvent. The as-synthesized nanoparticles were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM) coupled with energy-dispersive X-ray (EDX), photoluminescence (PL), and UV-vis near-infrared (NIR) spectroscopy. Their electrochemical potential was examined in [Fe(CN)] 4- /[Fe(CN)] 3- by cyclic and square wave voltammetry (CV and SWV) and electrochemical impedance spectroscopy (EIS). GCEBi 2 S 3 and GCESb 2 S 3 exhibit promising electrochemical performance and a higher specific capacitance of about 700-800 F/g in [Fe(CN)] 4- /[Fe(CN)] 3 . Thin films of Bi 2 S 3 and Sb 2 S 3 were successfully incorporated in the fabrication of solar cell devices. The fabricated device using Bi 2 S 3 (under 100 mW/cm 2 ) showed a power conversion efficiency (PCE) of 0.39%, with a V oc of 0.96 V, a J sc of 0.00228 mA/cm 2 , and an FF of 44%. In addition, the device exhibits nonlinear current density-voltage characteristics, indicating that Bi 2 S 3 was experiencing a Schottky contact. The Sb 2 S 3 -based solar cell device showed no connection in the dark and under illumination. Therefore, no efficiency was recorded for the device using Sb 2 S 3 , which indicated the ohmic nature of the film. This might be due to the current leakage caused by poor coverage. The nanoparticles were found to induce similar responses to the conventional semiconductor nanomaterials in relation to photoelectrochemistry. The present study indicates that Bi 2 S 3 and Sb 2 S 3 nanoparticles are promising semiconductor materials for developing optoelectronic and electrochemical devices as the films experience Schottky and Ohmic contacts., Competing Interests: The authors declare no competing financial interest., (© 2021 The Authors. Published by American Chemical Society.)

The incessant release of pharmaceuticals into the aquatic environment continues to be a subject of increasing concern. This is because of the growing demand for potable water sources and the potential health hazards which these pollutants pose to aquatic animals and humans. The inability of conventional water treatment systems to remove these compounds creates the need for new treatment systems in order to deal with these class of compounds. This review focuses on advanced oxidation processes that employ graphene-based composites as catalysts for the degradation of pharmaceuticals. These composites have been identified to possess enhanced catalytic activity due to increased surface area and reduced charge carrier recombination. The techniques employed in synthesizing these composites have been explored and five different advanced oxidation processes-direct degradation process, chemical oxidation process, photocatalysis, electrocatalyis processes and sonocatalytic/sono-photocatalytic processes-have been studied in terms of their enhanced catalytic activity. Finally, a comparative analysis of the processes that employ graphene-based composites was done in terms of process efficiency, reaction rate, mineralization efficiency and time required to achieve 90% degradation.

The co-existence of heavy metals and organics in industrial effluents is a prevalent problem. These pollutants usually have dissimilar compositions and properties, making their complete removal very tedious even with the use of conventional methods. In some cases, organics and heavy metals usually exist in a mixed matrix in industrial wastes. This poses harmful health risks to humans, aquatic lives and the entire ecosystem, because majority of these mixed pollutants amass in water in concentrations which are more than the permissible discharge limits in the environment. Therefore, it is necessary to remove these pollutants in order to prevent them from contaminating both the surface and ground water. Although, the removal of organic compounds and heavy metals (such as Hg, Pb, Cd, As and Cr) could be easily achieved individually, however, these pollutants exist together in many industrial effluents and even in surface waters. Hence the complete removal of these pollutants concurrently in a polluted system is the focus of this study. Several technologies have been used for the simultaneous removal of organics and heavy metal pollutants from water, which includes adsorption, ion exchange, photocatalysis, and coagulation. The success of these techniques depends on the water matrices and the choice of water treatment media such as adsorbents, resins, photocatalysts, and coagulants. The advantages and limitations of these technologies together with their respective mathematical modelling is critically examined in this review. Finally, the effect of joint existence of organic pollutants and heavy metals on the removal efficiency were examined in addition to the mathematical models that discusses the mechanisms of their combine elimination., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

The increase in the presence of highly recalcitrant poly- and per- fluoroalkyl substances (PFAS) in the environment, plant tissues and animals continues to pose serious health concerns. Several treatment methods such as physical, biological and chemical processes have been explored to deal with these compounds. Current trends have shown that the destructive treatment processes, which offer degradation and mineralization of PFASs, are the most desirable process among researchers and policy makers. This article, therefore, reviews the degradation and defluorination processes, their efficiencies and the degradation mechanism of photon-based processes. It shows that high degradation and defluorination efficiency of PFASs could be achieved by photon driven processes such as photolysis, photochemical, photocatalysis and photoreduction. The efficiency of these processes is greatly influenced by the nature of light and the reactive radical generated in the system. The limitation of these processes, however, include the long reaction time required and the use of anoxic reaction conditions, which are not obtainable at ambient conditions., Competing Interests: The authors declare no conflict of interest., (© 2020 The Author(s).)

Waste water remediation of toxic metals and dyes could be complex to achieve owing to several factors. Various techniques have been developed for the removal of these pollutants. However, the success of these water treatment techniques mainly depends on the choice of appropriate media. Most of the commercial and chemically synthesized materials for water treatment create additional hazards due to the leaching of toxic chemicals into the process water. Consequently, studies on the development of better materials which could achieve high efficiency without posing any health risk led to the exploration of non-toxic composite materials such as those composed of cellulose and metal oxides. The focus is on the choice of materials and the best methods that allows their combination in order to address the pollution caused by heavy metals and dyes. This review critically analyses or assess the use of cellulose incorporated with metal oxides in the removal of toxic metals and dyes from industrial effluent. The nanocomposites have been accepted as a technique that circumvents the problems associated with the use of only metal oxides in water purification. They provide a platform for an improvement in the hydrophobicity of the composite with concomitant efficiency in adsorption and photocatalysis., (Copyright © 2020 Elsevier B.V. All rights reserved.)

A simple solvothermal decomposition of bismuth dithiocarbamate complex in oleylamine, oleic acid, and hexadecylamine at 180 °C, yielded bismuth sulphide nanomaterials of different morphologies represented as Bi 2 S 3 (OAm), Bi 2 S 3 (OAc) and Bi 2 S 3 (HDA) respectively. The bismuth complex, used as the single source precursor, was synthesized and characterised by elemental analysis, FTIR, and NMR spectroscopic techniques. The spectroscopic and micro analysis confirmed the proposed compound, while the as-prepared nanoparticles were characterized using UV-visible spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy dispersive spectrometer (EDS). The effects of the different solvent media on the structural properties of the obtained Bi 2 S 3 were investigated. An orthorhombic phase bismuthinite of varying intensities were obtained, with an indication that a bias of orientations existed in the (2 1 1) crystallographic planes in the Bi 2 S 3 (OAm) compared to the characteristic (1 3 0) diffraction peak of Bi 2 S 3 . The microscopic analysis showed a correlation between the nanoparticles' morphology and the type of solvent used, which also implied that the properties of Bi 2 S 3 were affected by the solvent medium., (© 2020 The Author(s).)

This work reports the photocatalytic degradation of methylene blue (MB) dye using SnS 2 and SnO 2 nanoparticles obtained from a solvothermal decomposition (in oleylamine) and pyrolysis (in a furnace) processes, respectively, of the diphenyltin(IV) p -methylphenyldithiocarbamate complex. The complex, which was used as a single-source precursor and represented as [(C 6 H 5 ) 2 Sn(L) 2 ] (L = p -methylphenyldithiocarbamato), was synthesized and characterized using various spectroscopic techniques and elemental analysis. The structural properties and morphology of the as-synthesized nanoparticles were studied using X-ray diffraction (XRD) technique and transmission electron microscopy (TEM). UV-visible spectroscopy was used to study the optical property. The hexagonal phase of SnS 2 and tetragonal SnO 2 nanoparticles were identified, which exhibited varying sizes of hexagonal platelets and rod-like morphologies, respectively. The direct band gap energies of both materials, estimated from their absorption spectra, were 2.31 and 3.79 eV for SnS 2 and SnO 2 , respectively. The photocatalytic performances of the SnS 2 and SnO 2 nanoparticle, studied using methylene blue (MB) as a model dye pollutant under light irradiation, showed that SnO 2 nanoparticles exhibited a degradation efficiency of 48.33% after 120 min reaction, while the SnS 2 nanoparticles showed an efficiency of 62.42% after the same duration of time. The higher efficiency of SnS 2 compared to the SnO 2 nanoparticles may be attributed to the difference in the structural properties, morphology and nature of the material's band gap energy.

Dithiocarbamate complexes have remained prominent as single source precursors for the synthesis of clean metal sulfide nanoparticles. This study reports the synthesis of lead sulfide (PbS) nanoparticles using some novel complexes of 1, 10-phenanthroline lead(II) bis( N -alkyl- N -phenyl dithiocarbamate), represented as [Pb(L 1 ) 2 phen] (1) and [Pb(L 2 ) 2 phen] (2) (where L 1 = bis( N -ethyl- N -phenyldithiocarbamate; L 2 = bis( N -butyl- N -phenyldithiocarbamate); phen = 1, 10 phenanthroline) as a single source precursors. The complexes (1 and 2) were synthesized and characterized using various spectroscopic techniques and elemental analysis. The nanoparticles were synthesized via a solvothermal approach in oleylamine, used as a capping agent, and were given as PbS(1) and PbS(2) from [Pb(L 1 ) 2 phen] (1) and [Pb(L 2 ) 2 phen] (2), respectively, which were characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM), and absorption spectroscopy. The diffraction patterns confirmed the formation of face-centered cubic phase PbS nanoparticles with a preferential growth orientation along the (200) plane. The TEM images showed that PbS(1) were of a spherical morphology, while the morphology of PbS(2) tended to produce short rods. This was due to variation in the functional group on the precursor compounds. This variation also resulted in the different band gap energies found such as 1.148 and 1.107 eV for PbS(1) and PbS(2), respectively, indicating a blue shift from the bulk.

Interest in the synthesis of Bi(III) and Sb(III) dithiocarbamate complexes is on the rise, and this has been attributed to their wide structural diversity and their interesting application as biological agents and in solid state/materials chemistry. The readily available binding sites of the two sulphur atoms within the dithiocarbamate moiety in the complexes confers a wide variety of geometry and interactions that often leads to supramolecular assemblies. Although none of the bismuth or antimony metals are known to play any natural biological function, their dithiocarbamate complexes, however, have proven very useful as antibacterial, antileishmanial, anticancer, and antifungal agents. The dithiocarbamate ligands modulate the associated toxicity of the metals, especially antimony, since bismuth is known to be benign, allowing the metal ion to get to the targeted sites; hence, making it less available for side and other damaging reactions. This review presents a concise chemistry and some known biological potentials of their trivalent dithiocarbamate complexes.

The synthesis of PbS nanostructures by microwave irradiation of single source precursor compounds in ethyleneglycol medium is reported. Pb(II) bis( N -ethyl- N -phenyldithiocarbamate) and Pb(II) bis( N -butyl- N -phenyldithiocarbamate) represented as complexes ( 1 ) and ( 2 ) respectively were utilised. The prepared PbS nanostructures were characterized using X-ray diffraction (XRD), Transmission electron microscopy (TEM), and absorption spectroscopy. The results showed that complex ( 1 ) can project the formation of nanorod with (111) basal plane, while ( 2 ) project the formation of nanocube with (001) basal plane. The formation of different morphologies in ethylene glycol may also be due to the selective binding to specific crystallite facets of the PbS through the hydroxyl groups of ethylene glycol. In the nanorod, the selective stabilization of the (111) face of PbS, resulted in anisotropic growth along the (100) face. The high resolution TEM images showed distinct lattice fringes which confirmed the crystallinity of the nanostructures. The band gap energies were obtained as 1.10 and 1.12 eV for the nanorods and nanocubes respectively, a significant blue shift from the bulk value (0.4 eV) which could be ascribed to quantum confinement effect. The result established the significant effect of the precursor type on the morphologies of the PbS.

Production and use of metallic nanoparticles have increased dramatically over the past few years and design of nanomaterials has been developed to minimize their toxic potencies. Traditional chemical methods of production are potentially harmful to the environment and greener methods for synthesis are being developed in order to address this. Thus far phytosynthesis have been found to yield nanomaterials of lesser toxicities, compared to materials synthesized by use of chemical methods. In this study nanoparticles were synthesized from an extract of leaves of golden rod (Solidago canadensis). Silver (Ag), gold (Au) and Ag-Au bimetallic nanoparticles (BNPs), synthesized by use of this "green" method, were evaluated for cytotoxic potency. Cytotoxicity of nanomaterials to H4IIE-luc (rat hepatoma) cells and HuTu-80 (human intestinal) cells were determined by use of the xCELLigence real time cell analyzer. Greatest concentrations (50 µg/mL) of Ag and Ag-Au bimetallic were toxic to both H4IIE-luc and HuTu-80 cells but Au nanoparticles were not toxic. BNPs exhibited the greatest toxic potency to these two types of cells and since AuNPs caused no toxicity; the Au functional portion of the bimetallic material could be assisting in uptake of particles across the cell membrane thereby increasing the toxicity.

Significant attention has been given to organotin(IV) dithiocabamate compounds in recent times. This is due to their ability to stabilize specific stereochemistry in their complexes, and their diverse application in agriculture, biology, catalysis and as single source precursors for tin sulfide nanoparticles. These complexes have good coordination chemistry, stability and diverse molecular structures which, thus, prompt their wide range of biological activities. Their unique stereo-electronic properties underline their relevance in the area of medicinal chemistry. Organotin(IV) dithiocabamate compounds owe their functionalities and usefulness to the individual properties of the organotin(IV) and the dithiocarbamate moieties present within the molecule. These individual properties create a synergy of action in the hybrid complex, prompting an enhanced biological activity. In this review, we discuss the chemistry of organotin(IV) dithiocarbamate complexes that accounts for their relevance in biology and medicine.

CaO nanoparticles have been prepared using CaCl 2 and aqueous extract of broccoli as a precursor and reducing agent, respectively. Different volumes of the aqueous broccoli extract were utilised to obtain Ca(OH) 2 and subsequent calcination gave CaO nanoparticles. The synthesised CaO was confirmed by powder X-ray diffraction (XRD). The morphology was studied using transmittance electron microscopy (TEM), and the surface composition of Ca(OH) 2 was explored using Fourier transform infrared spectroscopy. The major functional groups present in the capping material responsible for the reduction of the metal salt and the surface passivation of Ca(OH) 2 were identified. The XRD pattern revealed cubic phase for all the CaO nanoparticles, and the crystallite size was estimated using Scherrer's equation showed a variation which is dependent on the volume of the extract used. TEM analysis showed different shapes, while the selected area electron diffraction (SAED) results confirmed the crystallinity of the nanoparticles. Thermogravimetric analysis of Ca(OH) 2 showed the decomposition product to be CaO. Sample C3, which has the smallest particle size, was used as a catalyst for the degradation of bromocresol green via photo irradiation with ultraviolet light and the result revealed a degradation efficiency of 60.1%.

In this study, French marigold's leaf and flower were used for the synthesis of silver nanoparticles (SNPs) in order to explore their potentials towards bioreduction of Ag + to Agᵒ. The as-synthesised SNPs were characterised using UV-Vis spectroscopy, Fourier transform infrared (FTIR) spectroscopy, powder X-ray diffraction, transmission electron microscopy, and zeta-potential analysis. The results obtained showed that the particles are polydispersed with sizes in the range 15.8-42.8 nm. The bioreduction was believed to be due to the amides, aldehyde functional groups, and essential oils present in the extracts as confirmed by the FTIR analysis. The growth mechanism involved in the reaction was studied which revealed oriented attachment (OA) onwards Ostwald ripening in the case of the flower-mediated synthesis and typical OA in the leaf-mediated synthesis. The studied kinetics of the particle formation showed that the reaction is possibly a pseudo-first-order reaction with some diffusion-controlled mechanism which is driven by high surface area to volume ratio in both the leaf- and flower-mediated synthesis.

In this study, the conversion of silver ions into ∼30.74 nm sized silver nanoparticles (AgNPs) was achieved in 30 min at a reaction temperature of 80-90°C in aqueous leaf extract of Artemisia afra . The synthesised AgNPs showed surface plasmon resonance in the range of 423-438 nm. Spherical and face-centred cubic nanoparticles were confirmed by transmission electron microscope (TEM) and X-ray diffraction (XRD) analysis, respectively. Fourier transform infra-red (FTIR) results indicated that the obtained nanoparticles were stabilised and capped through the carbonyl and carboxylate ion groups possibly from flavonoids, terpenoids, phenolics and esters content of the extracts. In addition, the AgNPs were assessed for their biological potentials against some microbes and, also, their free radical scavenging ability was established. The AgNPs exhibited interesting antimicrobial and antioxidant properties better than the aqueous extract of A. afra.

Three Schiff base compounds, N 1 ,N 2 -bis(3-nitrobenzylidene)phenylene diamine (NBBA), 2-methyl- N -(3-nitrobenzylidene)aniline (MNBA) and N -(2-chlorobenzylidene)-4-nitroaniline (CBNA) were synthesized, characterised and applied for the first time as potential mild steel (MS) corrosion inhibitors in 1 M HCl at 30 °C. Fourier transform infra-red (FTIR), 1 H, 13 C Nuclear magnetic resonance (NMR) and Mass spectrometry (MS) were used for the characterisation of the compounds. The electrochemical studies and evaluation of corrosion inhibition potency were achieved using potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS) techniques. Density functional theory (DFT) calculations were further employed to describe the electronic distribution on the molecules and potential sites that aided corrosion inhibition. The results of the employed characterisation techniques confirmed the proposed structures of the compounds with the MS revealing the exact molecular mass of the compounds. Electrochemical results showed that the trend in inhibition efficiency of the three compounds was in the order: MNBA > NBBA > CBNA. MNBA recorded the highest inhibition efficiency at 100 ppm. Corrosion kinetics of the set of inhibitors was found to prefer the Langmuir adsorption isotherm with both physisorption and chemisorption mechanisms as revealed by ΔG values. In an effort to develop efficient corrosion inhibitors with non-toxic effect, low cost and multiple adsorption centres, these Schiff bases are presented.

A simple and cost-effective material composed of polyacrylonitrile nanofibers containing different concentrations of moringa (MR) leaf extracts was fabricated for antimicrobial properties and wound dressing. The fabricated materials were characterized by scanning electron microscopy, thermal gravimetric analysis, and Fourier transmission infrared spectroscopy. The antibacterial sensitivity of the developed polyacrylonitrile-moringa extract nanofibers was evaluated against Staphylococcus aureus and Escherichia coli by the agar diffusion method. A pronounced antibacterial activity was observed with the increase in the incorporated moringa leaf extract concentration within the polyacrylonitrile-moringa extract nanofibers against the bacterial strains. The best antibacterial sensitivity was observed for nanofibers containing 0.5 g of moringa leaf extract which had an inhibitory zone of 15 mm for E. coli and 12 mm for S. aureus . Furthermore, the cost-effective and biodegradable nanofibrous polyacrylonitrile-moringa extract nanofiber was also used to conduct further studies regarding wound dressing. The result reveals that the increase in the concentrations of moringa leaf extract influenced the healing properties of the material. For days 1, 4, and 7 of the wound dressing experiment, the % wound closure of the rat was the highest for the nanofiber containing 0.5 g of moringa leaf extract (35, 87, and 95%, respectively) compared to the positive control medical gauze (29, 75, and 93%, respectively)., Competing Interests: The authors declare no competing financial interest.

The title compound, [Cd 2 (C 7 H 10 NS 2 ) 4 ], is a neutral dinuclear cadmium(II) complex bearing four bis N , N -di-allyl-di-thio-carbamate ligands coordinating to two Cd II cations. In each of the monomeric subunits, there are four S atoms of two di-thio-carbamate ligands [Cd-S = 2.5558 (3), 2.8016 (3), 2.6050 (3) and 2.5709 (3) Å] that coordinate to one Cd II atom in a bidentate mode. The dimers are located over an inversion centre bridged by two additional bridging Cd-S bonds [2.6021 (3) Å], leading to a substantial distortion of the geometry of the monomeric subunit from the expected square-planar geometry. The five-coordinate environment around each of the Cd II ions in the dimer is best described as substanti-ally tetra-gonally distorted square pyramidal. The di-thio-carbamate groups are themselves planar and are also coplanar with the Cd II ions. The negative charge on these groups is delocalized by resonance across the S atoms bound to the Cd II cation. This delocalization of the π electrons in the di-thio-carbamate groups also extends to the C-N bonds as they reveal significant double bond character [C-N = 1.3213 (16) and 1.3333 (15) Å].

Nanoscience and nanotechnology represent new and enabling platforms that promise to provide broad range of novel and improved technologies for environmental, biological and other scientific applications. This study reports the synthesis of silver nanoparticles mediated by aqueous leaf extract of Lippia citriodora at two different temperatures of 50°C and 90°C. The synthesis of colloidal silver nanoparticles (AgNPs) was monitored by the use of UV-visible spectroscopy at different temperatures and time intervals. The surface plasmon bands (SPBs) showed peaks between 417 and 421nm at 90°C and around 430nm at 50°C, indicating a red shift at lower temperature. Fourier transform infrared (FTIR) analysis of the nanoparticles showed the presence of similar peaks found in the spectra of the plant extract. The size of the AgNPs was confirmed by transmission electron microscopy (TEM) which indicated an average size of 23.8nm (90°C) and 25nm (50°C). The nanoparticles showed better antimicrobial activities when compared to the crude plant extract against several screened pathogens: Gram negative (Escherichia coli, and Salmonella typhi) and Gram positive (Bacillus subtilis and Staphylococcus aureus) strains and a fungi organism; Candida albicans. In addition, the AgNPs showed good larvicidal efficacy against early 4th instar of Culex quinquefasciatus (a vector of lymphatic filariasis). Finally, the nanoparticles exhibited photocatalytic properties on an industrial waste pollutant, methylene blue., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Synthesis of metallic and semiconductor nanoparticles through physical and chemical routes has been extensively reported. However, green synthesized metal nanoparticles are currently in the limelight due to the simplicity, cost-effectiveness and eco-friendliness of their synthesis. This study explored the use of aqueous leaf extract of Costus afer in the synthesis of silver nanoparticles (CA-AgNPs). The optical and structural properties of the resulting silver nanoparticles were studied using UV-visible spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Fourier transform infra-red spectrophotometer (FTIR). TEM images of the silver nanoparticles confirmed the existence of monodispersed spherical nanoparticles with a mean size of 20 nm. The FTIR spectra affirmed the presence of phytochemicals from the Costus afer leaf extract on the surface of the silver nanoparticles. The electrochemical characterization of a CA-AgNPs/multiwalled carbon nanotubes (MWCNT)-modified electrode was carried out to confirm the charge transfer properties of the nanocomposites. The comparative study showed that the CA-AgNPs/MWCNT-modified electrode demonstrated faster charge transport behaviour. The anodic current density of the electrodes in Fe(CN)₆] 4- /[Fe(CN)₆] 3- redox probe follows the order: GCE/CA-Ag/MWCNT (550 mA/cm²) > GCE/MWCNT (270 mA/cm²) > GCE (80 mA/cm²) > GCE/CA-Ag (7.93 mA/cm²). The silver nanoparticles were evaluated for their antibacterial properties against Gram negative ( Escherichia coli, Klebsiella pneumonia, Pseudomonas aeruginosa ) and Gram positive ( Bacillus subtilis and Staphylococcus aureus ) pathogens. The nanoparticles exhibited better inhibition of the bacterial strains compared to the precursors (leaf extract of Costus afer and silver nitrate). Furthermore, the ability of the nanoparticles to scavenge DPPH radicals at different concentrations was studied using the DPPH radical scavenging assay and compared to that of the leaf extract and ascorbic acid. The nanoparticles were better DPPH scavengers compared to the leaf extract and their antioxidant properties compared favorably the antioxidant results of ascorbic acid. The green approach to nanoparticles synthesis carried out in this research work is simple, non-polluting, inexpensive and non-hazardous.

The health challenges associated with pathogens and ectoparasites highlight the need for effective control approaches. Metal nanoparticles have been proposed as highly effective tools towards combatting different microbial organisms and parasites. The present work reports the antimicrobial and larvicidal potential of biosynthesized Ag/Ag₂O nanoparticles using aqueous leaf extract of Eupatorium odoratum (EO). The constituents of the leaf extract act as both reducing and stabilizing agents. The UV-VIS spectra of the nanoparticles showed surface plasmon resonance. The particle size and shape of the nanoparticles was analysed by transmission electron microscopy (TEM). The larvicidal study was carried out using third and fourth instar Culex quinquefasciatus larvae. The mosquito larvae were exposed to varying concentrations of plant extract (EO) and the synthesized nanoparticles, and their percentage of mortality was accounted for at different time intervals of 12 h and 24 h periods of exposure. The nanoparticles were more lethal against third and fourth instars of Culex quinquefasciatus larvae at the 24 h period of exposure with lower lethal concentration values (LC50 = 95.9 ppm; LC90 = 337.5 ppm) and (LC50 = 166.4 ppm; LC90 = 438.7 ppm) compared to the plant extract (LC50 = 396.8 ppm; LC90 = 716.8 ppm and LC50 = 448.3 ppm; LC90 = 803.9 ppm, respectively). The antimicrobial properties of the nanoparticles were established against different clinically-isolated microbial strains and compared to that of the plant extract (EO) and standard antimicrobial drugs. The nanoparticles were generally more active than the plant extract against the selected microbial organisms. The Gram-negative bacterial strains Escheerichua coli and Salmonella typhi were more susceptible towards the nanoparticles compared to the Gram-positive strains and the fungal organism.

The macrocylic ligand, 1,8-dimethyl-1,3,6,8,10,13-hexaazacyclotetradecane (MHACD) was synthesized by the demetallation of its freshly synthesized Ni(II) complex (NiMHACD). Successful synthesis of NiMHACD and the free ligand (MHACD) was confirmed by various characterization techniques, including Fourier transform infra-red (FT-IR), proton nuclear magnetic resonance (¹H-NMR), carbon-13 nuclear magnetic resonance ( 13 C-NMR), ultraviolet-visible (UV-vis), and energy dispersive x-ray (EDX) spectroscopic techniques. The anti-bacteria activities of MHACD were investigated against Staphylococcus aureus and Enterococcus species and the results showed that MHACD possesses a spectrum of activity against the two bacteria. The electrochemical cyclic voltammetry study on MHACD revealed that it is a redox active compound with promising catalytic properties in electrochemical applications. The inhibition potential of MHACD for mild steel corrosion in 1 M HCl was investigated using potentiodynamic polarization method. The results showed that MHACD inhibits steel corrosion as a mixed-type inhibitor, and the inhibition efficiency increases with increasing concentration of MHACD. The adsorption of MHACD obeys the Langmuir adsorption isotherm; it is spontaneous and involves competitive physisorption and chemisorption mechanisms. Quantum chemical calculations revealed that the energy of the highest occupied molecular orbital (HOMO) of MHACD is high enough to favor forward donation of charges to the metal during adsorption and corrosion inhibition. Natural bond orbital (NBO) analysis revealed the presence of various orbitals in the MHACD that are capable of donating or accepting electrons under favorable conditions.

Bipyridine adducts of N-phenyldithiocarbamato complexes, [ML(1)2L(2)] (M=Cd(II), Zn(II); L(1)=N-phenyldithiocarbamate, L(2)=2,2' bipyridine), have been synthesized and characterised. The decomposition of these complexes to metal sulphides has been investigated by thermogravimetric analysis (TGA). The complexes were used as single-source precursors to synthesize MS (M=Zn, Cd) nanoparticles (NPs) passivated by hexadecyl amine (HDA). The growth of the nanoparticles was carried out at two different temperatures: 180 and 220 °C, and the optical and structural properties of the nanoparticles were studied using UV-Vis spectroscopy, photoluminescence spectroscopy (PL), transmission emission microscopy (TEM) and powdered X-ray diffraction (p-XRD). Nanoparticles, whose average diameters are 2.90 and 3.54 nm for ZnS, and 8.96 and 9.76 nm for CdS grown at 180 and 220 °C respectively, were obtained., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Heteroleptic complexes of zinc(II), copper(II), manganese(II), and cobalt(II) of the types [MLL'(H2O)2]·nH2O and [MLL']·nH2O have been synthesized using sodium N-methyl-N-phenyldithiocarbamate (L) and benzoylacetone (L'). The metal complexes were characterized by elemental analysis, electrical conductance, magnetic susceptibility, infrared (IR), and UV-visible spectroscopic studies. The electrical conductance measurements revealed the nonelectrolytic nature of the synthesized complexes. The results of the elemental analyses, magnetic susceptibility measurements, and electronic spectra inferred that the Zn(II) complex adopted a four-coordinate geometry while the Co(II), Cu(II), and Mn(II) complexes assumed octahedral geometries. The IR spectra showed that the metal ions coordinated with the ligands via the S- and O-donor atoms. The geometry, electronic, and thermodynamic parameters of the complexes were obtained from density functional theory (DFT) calculations. The spin density distributions, relative strength of H-bonds, and thermodynamic parameters revealed that the order of stability of the metal complexes is Mn < Co < Cu > Zn. The agar diffusion methods were used to study the antimicrobial activity of the complexes against two Gram positive bacteria (S. aureus and S. pneumoniae), one Gram negative bacterium (E. coli), and two fungi organisms (A. niger and A. candida) and the complexes showed a broad spectrum of activities against the microbes.

A series of mixed ligand dithiocarbamate complexes with a general formula [ML2(py)2], where M = Mn(II), Co(II), Ni(II), and Cu(II), py = pyridine, and L = N-methyl-N-phenyl dithiocarbamate have been prepared and characterised by elemental analysis, FTIR and Uv spectroscopy, magnetic moment, and thermogravimetric and conductance analysis. The infrared spectra showed that symmetrical bidentate coordination occurred with the dithiocarbamate moiety through the sulfur atoms, while neutral monodentate coordination occurred through the nitrogen atom for the pyridine molecule in the complexes. The electronic spectra, elemental analysis, and magnetic moment results proved that the complexes adopted octahedral geometry. The conductance measurement showed that the complexes are nonelectrolytes proving their nonionic nature. The compounds were screened for three human pathogenic fungi: Aspergillus flavus, Aspergillus niger, and Candida albicans. The cobalt complex showed the best antifungal activity among the test compounds. Liquid-liquid extractive abilities of the ligand towards copper and nickel ions in different solvent media were investigated. The ligand showed a strong binding affinity towards the metals ions with an extractive efficiency of about 99%.