Biosynthesis of silver nanoparticles using oak leaf extract and their application for electrochemical sensing of hydrogen peroxide

Eco-friendly nanoparticles: mechanisms and capacities for efficient removal of heavy metals and phosphate from water using definitive screening design approach

Can nano-zero-valent iron, synthesized using oak leaf extract, be the key solution for water preservation, efficiently removing heavy metal ions and phosphate anions simultaneously? This research unveils how this technology not only promises high efficiency in the remediation of water resources, but also sets new standards for environmentally friendly processes. The high antioxidant capacity and high phenol content indicate suggest the possibility of oak-nZVI synthesis using oak leaf extract as a stable material with minimal agglomeration. The simultaneous removal of Cd and phosphates, as well as and Ni and phosphates was optimized by a statistically designed experiment with a definitive screening design approach. By defining the key factors with the most significant impact, a more efficient and faster method is achieved, improving the economic sustainability of the research by minimizing the number of experiments while maximizing precision. In terms of significance, four input parameters affecting process productivity were monitored: initial metal concentration (1-9 mg L-1), initial ion concentration (1-9 mg L-1), pH value (2-10), and oak-nZVI dosage (2-16 mL). The process optimization resulted in the highest simultaneous removal efficiency of 98.99 and 87.30% for cadmium and phosphate ions, respectively. The highest efficiency for the simultaneous removal of nickel and phosphate ions was 93.44 and 96.75%, respectively. The optimization process fits within the confidence intervals, which confirms the assumption that the selected regression model well describes the process. In the context of e of the challenges and problems of environmental protection, this work has shown considerable potential and successful application for the simultaneous removal of Cd(II) and Ni(II) in the presence of phosphates from water.

Environmental sustainable: Biogenic copper oxide nanoparticles as nano-pesticides for investigating bioactivities against phytopathogens

Endocrine-disrupting chemicals (EDCs) are of interest in human physiopathology and have been extensively studied for their effects on the endocrine system. Research also focuses on the environmental impact of EDCs, including pesticides and engineered nanoparticles, and their toxicity to organisms. Green nanofabrication has surfaced as an environmentally conscious and sustainable approach to manufacture antimicrobial agents that can effectively manage phytopathogens. In this study, we examined the current understanding of the pathogenic activities of Azadirachta indica aqueous formulated green synthesized copper oxide nanoparticles (CuONPs) against phytopathogens. The CuONPs were analyzed and studied using a range of analytical and microscopic techniques, such as UV-visible spectrophotometer, Transmission electron microscope (TEM), Scanning electron microscope (SEM), X-ray diffraction (XRD) and Fourier transformed infrared spectroscopy (FTIR). The XRD spectral results revealed that the particles had a high crystal size, with an average size ranging from 40 to 100 nm. TEM and SEM images were utilized to verify the size and shape of the CuONPs, revealing that they varied between 20 and 80 nm. The existence of potential functional molecules involved in the reduction of the nanoparticles was confirmed by FTIR spectra and UV analysis. Biogenically synthesized CuONPs revealed significantly enhanced antimicrobial activities at 100 mg/L concentration in vitro by the biological method. The synthesized CuONPs at 500 μg/ml had a strong antioxidant activity which was examined through the free radicle scavenging method. Overall results of the green synthesized CuONPs have demonstrated significant synergetic effects in biological activities which can play a crucial impact in plant pathology against numerous phytopathogens.

Biosynthesis of silver nanoparticles using extract of Rumex nepalensis for bactericidal effect against food-borne pathogens and antioxidant activity

The evolution and incidence of multidrug-resistant food-borne pathogens still become a critical public health global issue. To avert this challenge there is great interest in medical applications of silver nanoparticles. Thus, this study aimed to synthesize silver nanoparticles (Rn-AgNPs) using aqueous leaf extract of Nepal Dock (Rumex nepalensis Spreng) and evaluate their antibacterial potential against food-borne pathogens and antioxidant activity. The Rn-AgNPs were characterized by UV-Vis spectrophotometry, Dynamic Light Scattering (DLS), Scanning Electron Microscopy (SEM), and Fourier Transform Infra-Red Spectroscopy (FTIR). The antibacterial activities of the Rn-AgNPs were evaluated using agar well diffusion (zone of inhibition, ZOI) and microdilution (minimum inhibitory concentration, MIC and minimum bactericidal concentration, MBC) methods. The antioxidant property of the Rn-AgNPs was investigated using radical scavenging (DPPH and hydroxyl) assays. The UV-Vis spectra of Rn-AgNPs elucidated the absorption maxima at 425 nm and FTIR detected numerous functional groups of biological compounds that are responsible for capping and stabilizing Rn-AgNPs. DLS analysis displayed monodispersed Rn-AgNPs of 86.7 nm size and highly negative zeta potential (-32.5 mV). Overall results showed that Escherichia coli was the most sensitive organism, whereas Staphylococcus aureus was the least sensitive against Rn-AgNPs. In the antioxidant tests, the AgNPs radical scavenging activity reached 95.44% at 100 μg/ml. This study indicates that Rn-AgNPs exhibit a strong antimicrobial on L. monocytogenes, S. aureus, S. typhimurium, and E. coli and antioxidant and thus might be developed as a new type of antimicrobial agent for the treatment of multidrug-resistant foodborne pathogens and extensible applications in nanomaterial food- and nanocomposite-based antimicrobial packaging and/or as an antioxidant.

Controllable synthesis and stabilization of Tamarix aphylla-mediated copper oxide nanoparticles for the management of Fusarium wilt on musk melon

Excessive use of pesticides and mineral fertilizers poses a serious threat to ecoenvironment sustainability and human health. Nano pesticides or Nano fungicides have attained great attention in the field of agriculture due to their unique characteristics, by improving crop growth with enhancing pathogenesis-related defense system. However, there is a need to develop a sustainable mechanism for the synthesis of fungicides which replace the chemical pesticides to avoid their hazardous impact. Here in, Tamarix aphylla mediated CuO-Nanoparticles (NPs) were synthesized, characterized and their activity was evaluated under in-vitro and in-vivo conditions. The structural and elemental analysis of NPs were carried out by using X-ray powder diffraction (XRD), Fourier transformed infrared spectroscopy (FTIR), UV-visible spectrophotometer, Scanning electron microscope (SEM) and Transmission electron microscope (TEM). In the greenhouse, at an optimum concentration of 50 mg/L reduced disease severity very effectively and enhanced plant growth. Application of NPs also assisted in the induction of systemic response of defense-related genes in melon. Under In vitro condition at 100 mg/L significantly reduced mycelial growth (84.5%) by directly acting on the pathogenic cell wall. Our work confirmed that dosedependent concentration of T. aphylla extract based biological CuO-NPs enhance plant growth and help to effectively resist against F. oxysporum infection.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13205-022-03189-0.

Investigation of antibacterial, antifungal, antibiofilm, antioxidant and anticancer properties of methanol extracts of Salvia marashica İlçim, Celep & Doğan and Salvia caespitosa Montbret & Aucher ex Benth plants with medicinal importance

In this study, Antimicrobial, Antifungal and Antibiofilm activity tests on 16 bacteria and 2 fungi of Salvia marashica İlçim, Celep & Doğan and Salvia caespitosa Montbret & Aucher ex Benth species were performed by Agar Well Diffusion and Microdilution methods. Salvia species showed sensitivity with a zone diameter of 12-16 mm. Concentrations of 0.5 mg/ml to 16 mg/ml by the dilution method were used to determine the Minimum inhibited concentration (MIC) and Minimum bactericidal concentration (MBK). The MIC values of the plants are mostly 0.5 mg/ml - 4 mg/ml and MBC values are between 0.5 mg/ml - 8 mg/ml. Antifungal activity findings are remarkable on the species and it has been observed to have very high effects especially on Candida parapsilosis. When the antioxidant research findings are examined; It was observed that Salvia marashica and Salvia caespitosa plants have approximately 75% antioxidant activity at 1 mg/ml, and findings mostly directly proportional between concentrations and antioxidant activity capacity were recorded. MCF-7 and HUVEC cell lines were used to investigate anticancer activity properties. In line with the findings, while the IC50 value of Salvia marashica on the MCF-7 Cell line was 0.125 mg/ml, it was 1.65 mg/ml in the HUVEC cell line, while the IC50 value of Salvia caespitosa on the MCF-7 Cell line was 0.115 mg/ml in the HUVEC Cell line. It was found to be 9.87 mg/ml. It has been proven that both Salvia species have a cytotoxic effect on the MCF-7 Cell line.

Determination of Salicylic Acid Using a Highly Sensitive and New Electroanalytical Sensor

Background:

A drug sensor (salicylic acid, in this case) was designed and made up of this research. The senor was made by modification of paste electrode (MPE) with CuO-SWCNTs and 1-hexyl-3-methylimidazolium chloride (HMICl). The MPE/CuO-SWCNTs/HMICl showed catalytic activity for the oxidation signal of salicylic acid in phosphate buffer solution.

Methods:

Electrochemical methods were used as a powerful strategy for the determination of salicylic acid in pharmaceutical samples. Aiming at this goal, carbon paste electrode was amplified with conductive materials and used as a working electrode.

Results:

The MPE/CuO-SWCNTs/HMICl was used for the determination of salicylic acid in the concentration range of 1.0 nM – 230 µM using differential pulse voltammetric (DPV) method. At pH=7.0, as optimum condition, the MPE/CuOSWCNTs/HMICl displayed a high-quality ability for the determination of salicylic acid in urine, pharmaceutical serum, and water samples.

Conclusion:

The MPE/CuO-SWCNTs/HMICl was successfully used as a new and high performance working electrode for the determination of salicylic acid at a nanomolar level and in real samples.

Recent Advantages of Mediator Based Chemically Modified Electrodes; Powerful Approach in Electroanalytical Chemistry

Background:

Modified electrodes have advanced from the initial studies aimed at understanding electron transfer in films to applications in areas such as energy production and analytical chemistry. This review emphasizes the major classes of modified electrodes with mediators that are being explored for improving analytical methodology. Chemically modified electrodes (CMEs) have been widely used to counter the problems of poor sensitivity and selectivity faced in bare electrodes. We have briefly reviewed the organometallic and organic mediators that have been extensively employed to engineer adapted electrode surfaces for the detection of different compounds. Also, the characteristics of the materials that improve the electrocatalytic activity of the modified surfaces are discussed.

Objective:

Improvement and promotion of pragmatic CMEs have generated a diversity of novel and probable strong detection prospects for electroanalysis. While the capability of handling the chemical nature of the electrode/solution interface accurately and creatively increases , it is predictable that different mediators-based CMEs could be developed with electrocatalytic activity and completely new applications be advanced.

Properties and Recent Advantages of N,N’-dialkylimidazolium-ion Liquids Application in Electrochemistry

:

N,Nʹ-dialkylimidazolium-ion liquids is one of the important ionic liquids with a wide range of application as conductive electrolyte and in electrochemistry. The modified electrodes create a new view in fabrication of electroanalytical sensors. Many modifiers have beeen suggested for modification of electroanalytical sensor since many years ago. Over these years, ionic liquids and especially room temperature ionic liquids have attracted more attention due to their wide range of electrochemical windows and high electrical conductivity. N,Nʹ-dialkylimidazolium-ion liquids are one of the main important ionic liquids suggested for modification of bare electrodes and especially carbon paste electrodes. Although many review articles have reported onthe use of ionic liquids in electrochemical sensors, no review article has been specifically introduced so far on the review of the advantages of N,Nʹ-dialkylimidazolium ionic liquid. Therefore, in this review paper we focused on the introduction of recent advantages of N,Nʹ-dialkyl imidazolium ionic liquid in electrochemistry.

Fabrication of Electrochemical Sensor for Epinine Determination Amplified with MgO/CNTs Nanocomposite and Ionic Liquid

Background:

Catecholamines are a large group of pharmacological and biological compounds that are widely used in biological systems. These compounds are prepared both naturally and synthetically with many key roles in the human body and its activities. Therefore, many researchers focused on the identification and determination of catecholamines in biological samples.

Methods:

MgO/SWCNTs were synthesized through the chemical precipitation method. In addition, cyclic voltammetry, differential pulse voltammetry, and chronoamperometric methods were used for the electro-oxidation reaction study of epinine at the surface of the modified electrode.

Results:

Carbon paste electrode (CPE) modified with MgO/SWCNTs nanocomposite and 1-butyl- 3-methylimidazolium methanesulfonate (BMMS) was used as an electrochemical sensor for the determination of epinine. The results showed a linear dynamic range of 5.0 nM-250 μM with a detection limit of 0.1 nM for epinine determination using MgO/SWCNTs/BMMS/CPE as a sensor.

Conclusion:

In the present study, a highly sensitive electrochemical sensor was designed and fabricated as an analytical tool for the determination of epinine. MgO/SWCNTs/BMMS/CPE was successfully used for the determination of epinine in water and dextrose saline with an acceptable recovery range of 98.7%-102.72%.

Electro-catalytic amplified sensor for determination of N-acetylcysteine in the presence of theophylline confirmed by experimental coupled theoretical investigation

The 1,l/-bis(2-phenylethan-1-ol)ferrocene, 1-butyl-3-methylimidazolium hexafluoro phosphate (BMPF6) and NiO-SWCNTs were used to modify carbon paste electrode (BPOFc/BMPF6/NiO-SWCNTs/CPE), which could act as an electro-catalytic tool for the analysis of N-acetylcysteine in this work. The BPOFc/BMPF6/NiO-SWCNTs/CPE with high electrical conductivity showed two completely separate signals with oxidation potentials of 432 and 970 mV for the first time that is sufficient for the determination of N-acetylcysteine in the presence of theophylline. The BPOFc/BMPF6/NiO-SWCNTs/CPE showed linear dynamic ranges of 0.02–300.0 μM and 1.0–350.0 μM with the detection limit of ~ 8.0 nM and 0.6 μM for the measurement of N-acetylcysteine and theophylline, respectively. In the second part, understanding the nature of interaction, quantum conductance modulation, electronic properties, charge density, and adsorption behavior of N-acetylcysteine on NiO–SWCNTs surface from first-principle studies through the use of theoretical investigation is vital for designing high-performance sensor materials. The N-acetylcysteine molecule was chemisorbed on the NiO–SWCNTs surface by suitable adsorption energies (− 1.102 to − 5.042 eV) and reasonable charge transfer between N-acetylcysteine and NiO–SWCNTs.