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Deep eutectic solvents (DES), which have low toxicity and are low cost, biodegradable, and easily synthesized, were used for the extraction of neutral red (NR) dye before its spectrophotometric analysis. DES, containing choline chloride as a hydrogen bond acceptor and phenol as a hydrogen bond donor with a molar ratio of 1:2, was used for the extraction of NR dye from aqueous media. The possible interaction of different DESs with NR was studied using density functional theory (DFT) calculations. Experimentally, a UV-visible spectrophotometer was used for the quantitative analysis. The most important parameters affecting method performance, such as pH, extraction temperature, DES type, its volume, THF volume, sonication time, and centrifugation time, were optimized. The developed method provides exceptional sensitivity in terms of LOD and LOQ, which were 2.2 and 7.3 µg/L respectively. The relative standard deviation was 1.35–1.5% (n = 10), and the pre-concentration factor was 40. The method was found to be linear in the range of 2–300 µg/L (R2 = 0.9967). The method was successfully used for the determination of NR in wastewater samples. Finally, the DES-based method presents operational simplicity, high sensitivity, and rapid determination (<5 min) compared with other analytical procedures. [ABSTRACT FROM AUTHOR]

In this study, we have designed and explored a new series of non-fullerene acceptors for possible applications in organic solar cells. We have designed four molecules named as APH1 to APH4 after end-capped modification of recently synthesized Y6-Se-4Cl molecule. Density functional theory and time dependent-density functional theory have been employed for computing geometric and photovoltaic parameters of the designed molecules. Designed molecules have displayed high values of fill factor and FF%. Further, high mobility of electrons and holes between metal electrodes are also noted for designed molecules. Good values of open circuit voltage enhance the power conversion efficiency in the APH1–APH4. Frontier molecular orbitals analysis and excitation energy values suggested easy transportation of charges between molecular orbitals. Moreover, red-shifting in the absorption spectrum with high oscillating strength is also noted in APH1 to APH4 as compared to reference molecules. Results of different opto-electronic and photovoltaic parameters recommended that APH1 to APH4 are effective contributors for the development of high performance organic solar cells. [ABSTRACT FROM AUTHOR]

A new protocol for the determination of natamycin – an antifungal agent used as a food preservative - in cheese samples – is described. This new method is based on a natural deep eutectic solvent (NADES) green extraction procedure. High-performance liquid chromatography (HPLC) was used for detection and quantification. NADESs with different molar ratios were evaluated for efficient and selective extraction. NADES made of thymol and nonanoic acid (1:1) revealed to be the best extracting solvent. All significant analytical parameters - pH, temperature, NADES volume, time for sonication were optimized using Plackett-Burman (PB) and central composite design (CCD) - response surface methodology (RSM). Optimum conditions for extraction were pH 7, temperature 25°C, NADES volume 4.5 mL for 20 mL sample, and sonication time 10 mins. The developed method has a satisfactory linearity of 2–80.4 mg/kg, limits of detections (LOD), and limit of quantification (LOQ) of 0.45 and 1.45 mg/kg respectively. Under optimized conditions, the sample preparation procedure takes 12 mins. The method was found selective due to the unique and representative features of DESs. Furthermore, the extracts are analyzed by HPLC which provides a second very effective separation step, assuring the selectivity of the method. Validation of the method confirms the robustness and reproducibility of the NADES-based extraction coupled with the HPLC method demonstrating the effectiveness of NADES. The findings of this work contribute to the field of food safety and quality control, offering a novel and efficient approach to the detection of natamycin in cheese samples. [Display omitted] • Effective sample preparation for chromatographic analysis of natamycin • Green analytical chemistry approach for natamycin analysis in cheese samples • Robust, sensitive, and quick protocol for quality control of food • Optimization based on central composite design- Plackett-Burman • Effective analyte extraction based on molecular interactions including hydrogen bonding. [ABSTRACT FROM AUTHOR]

In this work, a cheap and widely applicable dispersive liquid-liquid microextraction (DLLME) method was developed for the extraction of Ni(II) and Cu(II) from water and food samples and analysis using flame atomic absorption spectrometry. DLLME was assisted by orbital shaker, while ferrofluid as an extractant was based on deep eutectic solvent (DES). This ferrofluid was made of hydrophobic DES (hDES), composed of lauric acid and menthol (molar ratio 1:2), and toner powder@aliquat 336 magnetic particles. The extraction procedure does not require any heating or centrifugation. The method limits of detection value were 0.15 µg L−1 and 0.03 µg L−1 for Ni(II) and Cu(II) respectively along with wide linearity range (0.4–250 µg L−1). The validation of the method was performed using certified reference materials (CRMs). The studies revealed excellent accuracy between results obtained by the developed method and expected values for all CRMs. The relative recoveries of Ni(II) and Cu(II) ions ranged from 92.8% to 98.6%. The developed method was further used for the determination of Ni(II) and Cu(II) in real water and food samples and provided quantitative recoveries. [Display omitted] • Magnetic DES: Toner powder@aliquat 336 / lauric acid:menthol as extractant. • Robust and time saving miniaturized sample preparation method. • Validated method reliable for routine analysis of Ni and Cu in water and food. • Short extraction time (8 min) and high preconcentration factor (125) were obtained. • Sensitive (ppb level), selective and stable method towards complex sample matrix. [ABSTRACT FROM AUTHOR]

This manuscript presents a new method for selective extraction and determination of fosetyl-aluminum in fruits and vegetable samples based on ultrasonic-assisted dispersive liquid-liquid microextraction method using ionic liquids (IL-UA-DLLME). A UV-Visible spectrophotometer was used for detection and quantification. Plants used for sample collection were grown under controlled conditions in a greenhouse. Central composite design (CCD)-response surface methodology (RSM) analysis was used for the optimization of significant factors (volume of IL, pH, ultrasonication time, and THF volume). Under optimal conditions, the limit of detection and limit of quantification of the IL-UA-DLLME procedure were 1.5 ng mL−1 and 5.0 ng mL−1 respectively with relative standard deviation 1.9–3.3%. The developed IL-UA-DLLME procedure demonstrated linearity within the concentration range of 5–600 ng mL−1 with an R2 value of 0.9914. The enrichment factor was 114 with a recovery% of 94.2–98.6% (n = 3) at optimal conditions. The IL-UA-DLLME assay was used for the analysis of fosetyl-aluminum in a variety of food samples and was found highly selective and efficient. [Display omitted] • Ionic liquid-based pre-concentration method for fosetyl-aluminum analysis in foods. • Increased mass transfer via DLLME for fungicide isolation from plant material. • Fully validated method with proved applicability to real samples and routine analysis. • A highly sensitive, selective, and robust assay for environmental monitoring. • Fast analyte isolation followed by spectroscopic final determination stage [ABSTRACT FROM AUTHOR]

[Display omitted] • Green chemistry sample preparation concept by means of Deep Eutectic Solvents (DES). • Novel DES based approach for pre-concentration of Niclosamide. • Effective method dedicated to determination of Niclosamide in pharmaceutical and wastewater samples. • Step forward for trace analysis of Niclosamide in environmental samples. The paper presents a simple, but very effective and sensitive spectrophotometric method for trace analysis of Niclosamide based on liquid–liquid microextraction using deep eutectic solvents (DESs) prior to its quantification. Here, different DES systems, such as Choline chloride (ChCl) + Urea, ChCl + Citric acid, ChCl + Ethylene glycol and ChCl + Phenol, were synthesized and evaluated at different molar ratios, selecting ChCl + Phenol 1:2 as an extractive DES system. Optimization studies revealed that best performance were obtained at pH 8 with optimum volume of THF and DES as 0.3 mL and 0.4 mL, respectively. The developed method is characterized by good analytical performance, e.g., a recovery of 99.26% and precision described by RSD value as <2%. The inter-assay precision was 0.51% while intermediate precision was 0.0323%. The method was found linear from 4.8 to 48 µg/L. LOD and LOQ were found as 0.112 and 0.374 µg/L, respectively. The paper presents also examples of the application of the proposed method for the determination of Niclosamide in different pharmaceutical and wastewater samples. This alternative method reveals a better performance in respect to the British pharmacopoeia procedure, providing concurrently ease of operation and simplicity. [ABSTRACT FROM AUTHOR]

A new assay based on effective (high recovery) extraction by means of deep eutectic solvents (DESs) was developed for ppb level determination of zinc in fishes and eel samples. Choline chloride and Phenol in a 1:2 M ratio was selected as optimal DES-based extraction solvent. 8-Hydroxy quinoline was used as a chelating agent for zinc ions. The optimized conditions were found at pH value of 8, ligand concentration of 10 mg/L, THF volumetric ratio in bulk solution of 0.5:10. The total time at optimal sample preparation conditions was 5 min for digested sample. Developed method fits to the purpose of routine analysis of fishes and eels. The LOD and LOQ were found 0.041 μg/kg and 0.136 μg/kg with pre-concentration factor of 25 and RSD 1.7%. [Display omitted] • Deep eutectic solvent based extraction of zinc from fish and eel samples. • Green chemistry approach for sample preparation. • FAAS determination of zinc in DES extract. • Novel application of DES in extraction techniques. • LOD at ppb level for zinc analysis. [ABSTRACT FROM AUTHOR]

This paper presents a new analytical procedure based on combination of homogeneous liquid–liquid extraction (HLLE) and vortex-assisted dispersive liquid–liquid microextraction (VA-DLLME) for the accurate and reliable determination of ochratoxin A (OTA) in dried fruit samples. To enable selective extraction of the OTA, six hydrophobic deep eutectic solvents (hDESs) were prepared and tested as extraction solvents. Optimization of DES volume, pH, NaCl amount, and mixing time affecting the efficiency of VA-DES-DLLME step was achieved by central composite design (CCD). Using optimized conditions, the working range was obtained in the range 0.4–350 ng mL−1 with an enrichment factor of 138. The limit of detection was 0.12 ng mL−1. To evaluate the accuracy of the method, the samples were analyzed with both the HLLE-VA-DES-DLLME procedure and reference method. The precision of the method was investigated by intraday/interday studies. The robustness of the method was also evaluated by making minor changes to the optimized conditions. The HLLE-VA-DES-DLLME procedure was successfully applied to dried fruit samples and quantitative recoveries were obtained (92.1–99.2%) confirming its usefulness for implementation in routine analysis of food samples. [Display omitted] • Novel sample preparation microextraction based protocol for OTA determination. • hDES based on hexafluoroisopropanol and carnitine provide best performance. • Application of chemometric approach for method optimization. • Minimization of solvent consumption, high selectivity and method robustness. • LOD, LOQ, and EF were found as 0. 21 ng mL−1, 0.40 ng mL−1, 138 respectively. [ABSTRACT FROM AUTHOR]

Developing an effective strategy to increase open circuit voltage with maximum PCE is vital to realizing high-performance OPVs (organic photovoltaic). In this report, a novel class of non-fullerene acceptor compounds has been constructed by us (D2APH1 to D2APH4) for high-performance OPVs. End-capped alterations of the JC2 (R) molecules were formed using capable end-capped units. A high Fill factor with FF% has been achieved with PCE of 30.34% for D2APH1 to D2APH4. Redshift and a limited energy band gap relative to the reference molecule, a change in the absorption spectra have been observed for D2APH1 to D2APH4. Further, designed molecules also expressed enhanced open-circuit voltage values and strong electron and hole mobility across metal electrodes. Easy exciton excitation inside an excited state is caused by low excitation energy and strong oscillation strength. The different geometric, photovoltaic, and optoelectronic analyses indicated that engineered molecules provide capable contributions to the creation of highly effective OPVs. In the present study, efficient molecules have been designed for the development of the active layer of the organic solar cell. Designed molecules expressed effective charge mobility with large light-harvesting ability. Designed molecules are effective candidates for the development of organic solar cells. [Display omitted] • New series of acceptor molecules (D2APH1-D2APH4) are studied for the active layer of organic solar cells. • Significant lowering of energy gap with concomitant red shifting of the absorption spectra is achieved with end-group engineering. • All acceptor molecules have remarkable optoelectronic properties compared to R. [ABSTRACT FROM AUTHOR]

In this paper, a green, cost-effective sample preparation method based on air assisted liquid phase microextraction (AA-LPME) was developed for the simultaneous extraction of As(III) and Sb(III) ions from vegetable samples using hydrophilic/hydrophobic natural deep eutectic solvents (NADESs). Central composite design was used for the optimization of extraction factors including NADES volume, extraction cycle, pH, and curcumin concentration. Limits of detection for As(III) and Sb(III) were 1.5 ng L−1 and 0.06 ng L−1, respectively. Working ranges for As(III) and Sb(III) were 0.2–300 ng L−1 (coefficient of determination (R2 = 0.9978) and 5–400 ng L−1 (R2 = 0.9996), respectively. Relative standard deviations for As(III) and Sb(III) were 2.2–2.8% and 2.9–3.2%, respectively. Enrichment factor of the method was 184 for As(III) and 172 for Sb(III). The accuracy and precision of the AA-NADES-LPME method were investigated by intraday/interday studies and standard reference material analysis, respectively. Finally, the AA-NADES-LPME method was successfully applied to microwave digested vegetable samples using the standard addition approach and acceptable recoveries were achieved. [Display omitted] • α-terpineol and octanoic acid-based NADES was prepared as extraction solvent. • The microextraction step was faster and did not require centrifugation and heating step. • The interaction between analytes and ligand was explained by computational study. • The method showed high sensitivity for As(III) and Sb(III). [ABSTRACT FROM AUTHOR]

Groundwater heavy metal pollution is a major concern all around the world. For the assessment of heavy metals and physico-chemical characteristics, groundwater samples were collected from different locations of the Karak District, Pakistan. With the help of the global information system device (GIS), groundwater samples were collected and studied from 47 locations. The present study focused on the water table (WT), water source depth (WSD), pH, electrical conductivity (EC), dissolved oxygen (DO), total dissolved solids (TDS), lead (Pb(II)), silver (Ag(I)), iron (Fe(II)) and chromium (Cr(VI)) parameters. Heavy metals were analyzed by the Atomic Absorption Spectrophotometer (AAS). The Pearson's matrix of correlation showed relationships between several parameters, such as the EC and the TDS which had close interactions between all the three different groundwater samples (collected by hand pump (HP), bore holes (BH) and tube wells (TW)). The strong correlation was detected in all the sources of water between the TDS and the EC, the regression coefficient (r) of which was 1. In the hierarchical clustering (by dendrograms) the HP samples show two clusters: Cluster 1 contains seven parameters and Cluster 2 has four parameters. The BH samples have two clusters: Cluster 1 contains three parameters and Cluster 2 has eight parameters. The TW dendrogram also shows two clusters: Cluster 1 contains six parameters while Cluster 2 has five parameters. [ABSTRACT FROM AUTHOR]

• Factors affecting the extraction recovery were optimized by a multivariate protocol. • Magnetic extraction solvent was prepared by mixing octanoic acid, aliquat-336 and CoCl 2. • Centrifugation step was not required to achieve phase separation. • Ease of operation, fast, and simplicity were the main advantages of the method. • The linear range and limit of detection were 3–600 ng mL−1 and 0.9 ng mL−1, respectively. In the current research, a fast and sustainable air-assisted hydrophobic magnetic deep eutectic solvent-based dispersive liquid phase microextraction followed by UV–Vis spectrophotometry measurements was optimized for the extraction and determination of melamine in milk and milk-based products. The central composite design was applied for the optimization of factors affecting the recovery of melamine. Quantitative extraction of melamine was achieved using hydrophobic magnetic deep eutectic solvents prepared from a mixture of octanoic acid, aliquat-336, and cobalt(II) chloride. The optimum conditions for extraction were found as follows: 6 extraction cycles, pH 8.2, extraction solvent volume 260 µL, and acetone volume 125 µL. Interestingly, a centrifugation step was not required to achieve phase separation. Under the optimum conditions, melamine was determined in the linear range of 3–600 ng mL−1, the limit of detection (3S blank /m) of 0.9 ng mL−1, and the enrichment factor of 144. The validation of the method was investigated by the analysis of reference materials. Consequently, the method was successfully applied for the analysis of melamine residues in milk and milk-based products. [ABSTRACT FROM AUTHOR]

The unplanned anthropogenic activities and raced industrial revolution detrimentally causes serious threat to terrestrial and aquatic life. A high discharge of wastewater from industries using dyes affects living organisms and the environment. This paper presents studies on polycationic selenides (PCS) synthesized by hydrothermal methods for photocatalytic degradation of dyes. The synthesized PCS were confirmed by various characterization techniques such as FTIR, SEM, EDX, UV/Vis, and XRD. The FTIR spectra revealed characteristic band at 843, 548 cm−1, and 417 cm−1 due to the M − Se stretching and intrinsic stretching vibrations, respectively. The optical bandgap of polycationic selenide lies in the visible light region (2.36 eV). The SEM images showed that PCS has a spherical shape with an average crystallite size of 29.23 nm calculated from XRD data using Scherer's equation. The PCS has a point of zero charge (PZC) at pH 7. The efficiency of synthesized PCS photocatalyst was confirmed in terms of its activity towards Eosin (EY) and Crystal violet (CV) dyes mineralization. The photocatalytic degradation for EY and CV dyes at optimum conditions was 99.47% and 99.31% and followed second order reactions kinetics with 1.4314 and 0.551 rate constant, respectively. The polynomial quadratic model is the best-fitted response surface methodology (RSM) model having a maximum desirability factors value and significant terms, with R2 (0.9994) and adj R2 values (1.0). [Display omitted] • Green fabrication of new ternary metallic selenides nanostructured materials. • Structural/morphological characteristics of ternary metallic selenides by advanced techniques. • Efficient photocatalytic degradation of textile contaminants under sunlight irradiation. • Operating factors influencing the degradation phenomena are investigated. [ABSTRACT FROM AUTHOR]