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This paper describes the simple and environmentally friendly production of AgNPs using Dimrit raisin, grown in Burdur, extract. To optimize the synthesis of AgNPs, a number of variables, including extract concentration, silver solution concentration, synthesis time, and synthesis temperature, were investigated. AgNPs were obtained after 173 h at 1% extract concentration and 10-1 M silver concentration. The structure of the synthesised AgNPs was investigated by Transmission electron microscopy (TEM), X-ray diffraction (XRD), UV-visible spectroscopy, and Fourier transform infrared spectroscopy (FT-IR). TEM analysis showed that the majority of the AgNPs had a spherical shape, and the average particle size was 30 nm. Antimicrobial activity was seen against Staphylococcus aureus ATTC43300, Enterococcus faecalis ATTC29212, Bacillus subtilis, Listeria monocytogenes, Klebsiella pneumoniae and Gram-negative Salmonella enterocolitis, E. coli 0157:H7 ATTC 43895, and Escherichia coli ATTC 35150. [ABSTRACT FROM AUTHOR]

In this study, the antimicrobial activity of silver nanoparticles (AgNPs L21, AgNPs L22) produced using aqueous extracts of the Laser trilobum harvested in 2021 and 2022 was optimized. The experimental design and optimization of antimicrobial activity were performed using the response surface method (RSM). Using RSM, independent variables, such as silver concentration, extraction time, and synthesis temperature, were optimized as a result of the inhibition zone diameter against Staphylococcus aureus, Escherichia coli, Salmonella Typhimurium, and Listeria monocytogenes. Based on the optimization results, the extraction time, silver concentration, and temperature for AgNP L21 and L22 synthesis were determined to be 60 min, 5 mM, and 25 °C, respectively. When the XRD and TEM results of the nanoparticles synthesized under optimal conditions were evaluated, it was determined that the AgNPs were spherical in shape and had an average size of 30 ± 12 nm. Our study revealed that the year of harvest is unimportant for nanoparticles synthesized from L. trilobum, using a cheap and simple method that does not require toxic substances. Owing to the antimicrobial activity of nanoparticles produced under optimal conditions, it is possible to biocontrol and prevent contamination by these bacteria in food science and industry. [ABSTRACT FROM AUTHOR]

The solvothermal approach was used to create a novel Eu metal-organic framework (Eu-MOF) based on 1,4-benzendicarboxylic acid (TPA), 1,10-phenanthroline, and N,N-dimethylformamide (DMF)/H 2 O. Structural analysis of Eu-MOF, Fluorescence spectrometry, Fourier Transform Infrared Spectrometer (FTIR), Scanning Electron Microscopy (SEM), Energy dispersive X-ray (EDX) mapping, Thermo-gravimetric analysis (TGA), and Single Crystal X-Ray Diffraction (PXRD) methods. Using the fluorescence properties of the synthesized Eu-MOF, its use as a fluorescence sensor in the determination of different analytes, such as organic molecules (T3-T4 hormone, ascorbic acid, and glucose) and metal ions (Na+, K+, Ca2+, Mg2+, Cu2+, Mn2+, Hg2+, Pb2+, Ni2+, Cr3+, Al3+, Fe3+), was investigated. Fluorescence experiments revealed that Cu2+, Ni2+ cations, as well as T3 and T4 hormones, quenched the fluorescence of Eu-MOF. Turn-off luminescence can be induced by 10 μM Cu2+, 30 μM Ni2+ cations, 500 nM T3, and 800 nM T4 hormones. Fluorescence quenching efficiencies were calculated for Cu2+, Ni2+, T3, and T4 99.7%, 99.6%, 98.7%, and 98.2%, respectively. [Display omitted] • Eu-MOF was synthesized by a one-step solvothermal method using a mixed-ligand strategy. • The Eu-MOF exhibited highly sensitive and selective detection of Cu2+ and Ni2+ cations. • The Eu-MOF metal sensor showed detection limit of 4.69 μM (for Cu2+) and 1.47 μM (for Ni2+). • The Eu-MOF was used for the determination of total thyroid hormones in serum samples. • The Eu-MOF hormone sensor showed a detection limit of 0.028 nM for total thyroid hormones. [ABSTRACT FROM AUTHOR]

Chocolate is consumed by people of all ages in every part of society. Chocolate is a very rich source of many essential metals for the body but it also may involve toxic metals. Therefore, the accurate and precise method should be selected and applied to determine the essential and toxic metals in the chocolate samples. In present study, Na, K, Mg (II), Ca(II), Cu(II), Fe(III), Zn(II), Cd(II), Cr(III), Pb(II) and Ni(II) metals were determined by using flame atomic absorption spectrometry (FAAS) in 24 different chocolate samples of 3 different types including 8 different brands of bitter, milk and white. The microwave-assisted digestion system was also used for the chocolate samples digestions. All results were given at 95% of confidence level. In addition, the accuracy of the method was also investigated by the analysis of a standard reference material (spinach leaves, NIST-1570a). [ABSTRACT FROM AUTHOR]

Commercial micro‐mesoporous carbonaceous material (MCM; 56.8% mesopores) was applied for investigating the removal phenomenon of naproxen drug in aqueous solutions through batch adsorption experiments. Results demonstrated that the adsorption capacity of MCM to naproxen was slightly affected by different pHeq (2.0–11) and ionic strength (0–1 M NaCl). Adsorption kinetics, isotherms, thermodynamics, and mechanisms were evaluated at pH 7.0. Adsorption kinetics indicated the rate constants for adsorption (0.2 × 10−3 L/(mg × min) and desorption (0.076/min) and the adsorption equilibrium constant (2.6 × 10−3 L/mg). Adsorption isotherm showed that MCM exhibited a high‐affinity adsorption capacity to naproxen (even at low concentrations) and its Langmuir maximum adsorption capacity (Qmax) was 252.7 mg/g at 25°C. Adsorption thermodynamics proved that the adsorption process was endothermic and physisorption (ΔH° = 9.66 kJ/mol). The analysis result of pore size distribution demonstrated that the internal pore structure of MCM was appropriate for adsorbing naproxen molecules. Pore‐filing mechanism (pore diffusion phenomenon) was confirmed by a considerable decrease in BET‐surface area (585 m2/g) and total pore volume (0.417 cm3/g) of MCM after adsorbing naproxen (~1000 mg/L and pH 7.0) at 5 min (341 and 0.256), 60 min (191 and 0.205), 120 min (183 and 0.193), 360 min (144 and 0.175), and 24 h (71.6 m2/g and 0.123 cm3/g, respectively). The pore diffusion occurred rapidly (even at the initial adsorption period of 5 min). The FTIR technique was applied to identify the existence of C–H···π and n–π interaction. π–π interaction (evaluated through ID/IG ratio and C=C band) played a minor contribution in adsorption mechanisms. The ID/IG ratio (determined by the Raman technique) of MCM before adsorption (1.195) was similar to that after adsorption (1.190), and the wavenumber (C=C band; its FTIR spectrum) slightly shifted from 1638 to 1634 cm−1 after adsorption. A decrease in the Qmax value of MCM from 249 to 217 (H2O2‐oxidized MCM) or to 224 mg/g (HNO3‐oxidized MCM) confirmed the presence of π–π interaction. Electrostatic attraction was a minor contribution. MCM can serve as a promising material for removing naproxen from water environment through a pore‐filling mechanism. Practitioner Points: Pore‐filling mechanism was proposed by comparing textural properties of MCM before and after adsorbing naproxen.C–H···π and n–π interactions were identified via FTIR technique.π–π interaction was observed by FTIR and Raman techniques.Oxidation of MCM with HNO3 or H2O2 was a helpful method to explore π–π interaction.Electrostatic attraction was explained through studies: effects of pH and NaCl along with desorption. [ABSTRACT FROM AUTHOR]

Pb(II) ions were separated/preconcentrated and detected by a two-step preconcentration method (Amberlite CG-120 resin and slotted quartz tube (SQT) flame atomic absorption). The first preconcentration step was the adsorption of Pb(II) on Amberlite CG-120 resin in the drinking, spring and lake water samples before detection and then its elution using 5 mL of 3 M nitric acid. The second preconcentration step was conducted using SQT device with flame atomic absorption detection. Using a two-step preconcentration method, enrichment factor of 560 was found and detection and quantitation limits were 0.23 and 0.8 µg/L, respectively. The accuracy of the method was tested by analysis of standard reference material (Environmental Matrix Reference Material, Lake Water, TMDA-70.2) at a 95% confidence level. [ABSTRACT FROM AUTHOR]

The ubiquitous appearance of nonsteroidal anti-inflammatory drugs (i.e., naproxen) in water bodies has raised enormous concerns among general public. Development of promising materials for eliminating such contaminants from water environment has attracted much attention in the scientific community. In this study, three (direct, post-treated and pre-treated) methods were developed to prepare biochars (800-PSB, 800-800-PSB, and 190-800-PSB, respectively) derived from the wastes of peanut shells (PS). They were thoroughly characterized by various important properties (i.e., porosity and superficial functional group) and applied to remove naproxen drug from water. Results indicated that although the pre- and post-treatments had a slight effect on the surface area of biochars (i.e., 571 m2/g for 800-PSB, 596 m2/g for 800-800-PSB, and 496 m2/g for 190-800-PSB), such treatments remarkably improved the adsorption capacity of biochar. The maximum adsorption capacity of biochar (obtained from the Langmuir model) towards naproxen in solution at 25 decreased in the following order: 800-800-PSB (324 mg/g) > 190-800-PSB (215 mg/g) > 800-PSB (105 mg/g). The thermodynamic study demonstrated that the adsorption was spontaneous and exothermic. Depending the preparation process, the contribution of each mechanism in the adsorption process was dissimilar. The overall adsorption mechanism was regarded as pore filling, π - π interaction, hydrogen bonding formations, n- π interaction, van der Waals force, and electrostatic attraction. Two methods used to identify the important role of π - π interaction were proposed herein. The possible desorption and reuse of laden-biochars were investigated by the chemical and thermal methods. The prepared biochar samples can serve as potential carbonaceous porous adsorbents for effectively removing naproxen from water media. Unlabelled Image • Different carbonization processes were applied to convert biomass into biochars. • Biochars were applied to remove naproxen from water and wastewater. • Biochar produced from interrupted pyrolysis exhibited excellent adsorption capacity. • Adsorption mechanism was explored and proposed from various experimental data. • Pore filling and π-π interaction played a proper role in adsorption mechanism. [ABSTRACT FROM AUTHOR]