Non-enzymatic electrochemical sensor for organophosphate pesticide (Parathion) has been developed for the first time by utilizing nickel oxide nanoplatelets modified screen-printed electrodes (SPEs). ...The NiO NPLs showed a superior electrochemical performance and ultrasensitive determination of parathion in real samples over bare/unmodified SPEs.
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•Meso-/macro-porous NiO nanoplatelets were synthesized by a simple hydrothermal method.•Sensitive determination of parathion pesticide by utilizing NiO NPLs modified SPE was explored.•NiO-SPEs can be used in a wide concentration range with low detection limit of 24 × 10−9 mol L−1.•The stability of NiO-SPEs nanozyme was utilized for detection of parathion in water, urine and vegetable samples.
Nanozyme-based electrochemical sensors have attracted much attention because of their low cost, sensitivity and remarkable stability under extensive environmental and industrial conditions. Interestingly, the physical characteristics of the nanomaterials in terms of size, shape, composition, surface area and porosity dominate the electrochemical processes at electrode surfaces. Herein, we explore nickel oxide nanoplatelets (NPs) modified screen-printed electrode-based nanozyme sensors that displays high electrochemical activity including stability, sensitivity, selectivity and applicability for organophosphate pesticide (Parathion) determination. Differential pulse voltammogram of NiO-SPE in presence of parathion showed a characteristic peak current at −1.0 V (vs. Ag/AgCl). The NiO-SPE platform allows determination of parathion over the concentration range of 0.1–30 µM with a limit of detection (LOD) of 0.024 µM. The sensing platform is found to detect parathion of interferences without compromising the sensitivity of the sensor. Such interesting features offer a sensitive determination of parathion in water, urine and vegetable samples.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Contamination of water supplies with different organic pollutants from industrial and agricultural activities has received high concern recent years. Thus, efficient removal of these organic ...pollutants and minimize their usage in environment are highly recommended. Herein, we report hydrothermal chemical modifications of commercial kaolin (CK) in presence of sodium hydroxide (alkaline-modified kaolin; AMK) and disodium hydrogen phosphate (phosphate-modified kaolin; PMK) reagents. Interestingly, these chemical modifications altered the physicochemical characteristics of CK in term of morphology, surface area and functionality which enhanced the adsorption capability of organic pollutants (i.e. methylene blue; MB) as well as offered an alternative inorganic pesticide that might reduce the consumption of organic pesticides. The results showed that, the equilibrium of MB adsorption is well described by Langmuir isotherm with maximum monolayer capacity of 434.78 and 476.19mg/g for AMK and PMK, respectively. Furthermore, AMK and PMK revealed reasonable latent entomotoxic effect against cotton leafworm (S. littoralis) compared to a highly toxic organic pesticide (i.e. Methomyl). Therefore, the naturally abundant kaolin can be utilized efficiently to mitigate the organic pollutants in environment through sequestering of organics and generation of alternative inorganic pesticides for green plant protection.
•Hydrothermal treatments of kaolin were carried out in presence of NaOH and Na2HPO4.•The modified kaolin was utilized to mitigate the organic pollutants in environment.•The MB adsorption is fitted by Langmuir model with adsorption capacity of 476.19mg/g.•Kaolin showed pesticidal activity against S. littoralis to minimize organics usage.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Land snails are the most harmful pests in agricultural fields. Eobania vermiculata is a widespread snail species that causes massive damage to all agricultural crops. Thus, the molluscicidal activity ...of calcium borate nanoparticles (CB-NPs) against Eobania vermiculata was evaluated and compared with metaldehyde (Gastrotox® E 5% G). The amorphous phase of CB-NPs was obtained after thermal treatment at a low temperature (500 °C) which conformed by X-ray diffraction (XRD) analysis. CB-NPs are composed of aggregated nano-sheets with an average thickness of 54 nm which enhanced their molluscicidal activity. These nano-sheets displayed meso-porous network architecture with pore diameters of 13.65 nm, and a 9.46 m
/g specific surface area. CB-NPs and metaldehyde (Gastrotox® E 5% G) exhibited molluscicidal effects on Eobania vermiculata snails with median lethal concentrations LC
of 175.3 and 60.5 mg/l, respectively, after 72 h of exposure. The results also showed significant reductions of Eobania vermiculata snails hemocytes' mean total number, the levels of Testosterone (T) and Estrogen (E), alkaline phosphatase, acid phosphatase, albumin, and protein concentrations, succinate dehydrogenase, glucose, triglycerides and phospholipids levels, while significant increases in the phagocytic index and mortality index, both transaminases (ALT and AST) and glycogen phosphorylase concentration were observed after the exposure to LC
of CB-NPs or metaldehyde (Gastrotox® E 5% G) compared to the control group. Therefore, CB-NPs could be used as an alternative molluscicide for controlling Eobania vermiculata, but further studies are needed to assess their effects on non-target organisms.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Recent advancements in electrode design are substantially linked to state-of-the-art nanomaterial fabrications. Herein, we report a simple one-pot hydrothermal synthesis of Cd(OH)
with a ...platelet-like morphology, which was subsequently annealed at relatively high temperatures to produce a CdO/Cd(OH)
nanocomposite for the first time. It was found that the control of thermal treatment allowed tunable charge transport across the nanometre scale due to the presence of CdO and Cd(OH)
mixed nanocrystals. The CdO/Cd(OH)
nanocrystals offer interesting prospects for the electrocatalytic oxidation of nitrite ions and for supercapacitor applications. The CdO/Cd(OH)
nanocomposite was blended with a trace amount of gold NPs for enhancing the electrochemical conductivity and electrocatalytic capability for nitrite oxidation with a sensitivity of 32.9 μA mM
. It afforded a promising electrocatalyst in a wide concentration range up to 10 mM with a low detection limit of 0.87 μM. Furthermore, the CdO/Cd(OH)
nanocomposite electrode was showed to be a highly active and stable supercapacitor, achieving a high specific capacitance in an alkaline medium of about 145 F g
at a discharge current of 2.0 A g
. These results have revealed that the presence of mixed oxide/hydroxide nanocrystals in nanoscale dimensions will be very interesting for various electrochemical applications and provide for a new class of nanodevices based on electrochemistry with unique capabilities.
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IJS, KILJ, NUK, UL, UM, UPUK
Herein, nanostructured metal oxides of essential soil nutrient elements (i.e., CuO and CaO) with definite shape and size were simply synthesized, and their pesticidal activities against cotton ...leafworm (Spodoptera littoralis) were explored for the first time. These metal oxide nanostructures represented novel economic and ecofriendly nanopesticides for sustainable plant protection and might boost the nutrient content of soil. The results showed that CuO nanoparticles (NPs) and CaO NPs exhibited potential entomotoxic effects against S. littoralis. Interestingly, CuO NPs exhibited fast entomotoxic effect with LC50 = 232.75 mg/L after 3 days, while CaO NPs showed a slow entomotoxic effect with LC50 = 129.03 mg/L after 11 days of post-treatments. The difference in the pesticidal activity of the metal oxides is related to their physical characteristics and interfacial surfaces upon insect midgut and cuticle layer of insect body wall. Thus, nanoengineered metal oxides might be utilized to generate an alternative and cost-effective pesticide formulation in the near future.
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IJS, KILJ, NUK, PNG, UL, UM, UPUK
The development of nanoagrochemicals has attracted much attention in the last decade to overcome the recent agricultural and environmental challenges associated with the intensive usage of ...insecticides. Herein, nanostructured calcium borate materials with hierarchical sea urchin-like microspheres and microblocks have been synthesized by a facile hydrothermal method. The insecticidal activity of CaB 2 O 4 and its synergistic combination with cholinesterase-inhibiting insecticides are explored against Spodoptera littoralis ( S. littoralis ) for the first time via a feeding bioassay protocol. The insecticidal efficacy of sea urchin-like microspheres (CB-A) is estimated to be LC 50 = 207 mg L −1 which is two-fold higher than that of microblocks (CBM-A) with LC 50 = 406 mg L −1 after eleven days of exposure. The synergistic combination of the CB-A sample with methomyl and chlorpyrifos increases the toxicity to 2.4 and 2.6-fold higher than that of the individual insecticides, respectively. Significantly, sea urchin-like CaB 2 O 4 microspheres cause physical damage to the external insect's cuticle layer, which consequently enhances the uptake of organic insecticides. Our results revealed that calcium borate micro-/nano-structures can be employed as a multifunctional nanoagrochemical in various agricultural programs for S. littoralis control and decrease the usage of cholinesterase-inhibiting insecticides.
Herein, silica nanostructures with various physicochemical characteristics were synthesized via surfactant-assisted methods. Potent entomotoxic effects of silica nanostructures were explored against ...cotton leaf worm (
Spodoptera littoralis
) for the first time by utilizing surface contact and feeding bioassay protocols. The mortality of the treated larvaes by surface contact was faster than feeding bioassay method. The results showed that the surface characteristics and particle size of silica nanostructures could effectively control their entomotoxic effects compared to commercial silica or even organic pesticides. It was also observed that the dead bodies of the insects became extremely dehydrated due to the damage of insect cuticular water barrier as a result of abrasion. Furthermore, the physical mode of action of silica nanostructures makes insects is unlikely to become physiologically resistant; hence, silica nanostructures can be efficiently used as a valuable tool in
S. littoralis
management programs.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Recent advancements in electrode design are substantially linked to state-of-the-art nanomaterial fabrications. Herein, we report a simple one-pot hydrothermal synthesis of Cd(OH)
2
with a ...platelet-like morphology, which was subsequently annealed at relatively high temperatures to produce a CdO/Cd(OH)
2
nanocomposite for the first time. It was found that the control of thermal treatment allowed tunable charge transport across the nanometre scale due to the presence of CdO and Cd(OH)
2
mixed nanocrystals. The CdO/Cd(OH)
2
nanocrystals offer interesting prospects for the electrocatalytic oxidation of nitrite ions and for supercapacitor applications. The CdO/Cd(OH)
2
nanocomposite was blended with a trace amount of gold NPs for enhancing the electrochemical conductivity and electrocatalytic capability for nitrite oxidation with a sensitivity of 32.9 μA mM
−1
. It afforded a promising electrocatalyst in a wide concentration range up to 10 mM with a low detection limit of 0.87 μM. Furthermore, the CdO/Cd(OH)
2
nanocomposite electrode was showed to be a highly active and stable supercapacitor, achieving a high specific capacitance in an alkaline medium of about 145 F g
−1
at a discharge current of 2.0 A g
−1
. These results have revealed that the presence of mixed oxide/hydroxide nanocrystals in nanoscale dimensions will be very interesting for various electrochemical applications and provide for a new class of nanodevices based on electrochemistry with unique capabilities.
A simple fabrication of CdO/Cd(OH)
2
nanocomposites was developed and explored for electrochemical-based devices. The nanocomposite is shown to be a sensitive electrode material for nitrite determination in water samples as well as a promising supercapacitor.
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IJS, KILJ, NUK, UL, UM, UPUK
The development of nanoagrochemicals has attracted much attention in the last decade to overcome the recent agricultural and environmental challenges associated with the intensive usage of ...insecticides. Herein, nanostructured calcium borate materials with hierarchical sea urchin-like microspheres and microblocks have been synthesized by a facile hydrothermal method. The insecticidal activity of CaB
2
O
4
and its synergistic combination with cholinesterase-inhibiting insecticides are explored against
Spodoptera littoralis
(
S. littoralis
) for the first time
via
a feeding bioassay protocol. The insecticidal efficacy of sea urchin-like microspheres (CB-A) is estimated to be LC
50
= 207 mg L
−1
which is two-fold higher than that of microblocks (CBM-A) with LC
50
= 406 mg L
−1
after eleven days of exposure. The synergistic combination of the CB-A sample with methomyl and chlorpyrifos increases the toxicity to 2.4 and 2.6-fold higher than that of the individual insecticides, respectively. Significantly, sea urchin-like CaB
2
O
4
microspheres cause physical damage to the external insect's cuticle layer, which consequently enhances the uptake of organic insecticides. Our results revealed that calcium borate micro-/nano-structures can be employed as a multifunctional nanoagrochemical in various agricultural programs for
S. littoralis
control and decrease the usage of cholinesterase-inhibiting insecticides.
Hierarchical sea urchin-like CaB
2
O
4
microspheres were synthesized and their synergistic combination with cholinesterase-inhibiting insecticides was explored against
Spodoptera littoralis
.
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