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Hydrophilic deep eutectic solvents based on choline chloride, carboxylic acids, and water are studied as “green” extractants for the liquid–liquid microextraction of lead from vegetable oils. An automated method is proposed for the microextraction of lead from vegetable oils into a ternary deep eutectic solvent based on choline chloride, lactic acid, and water. The carboxylic acid in the extractant ensured the effective mass transfer of lead due to complexation. Water in the extractant made it possible to reduce its viscosity to automate liquid–liquid microextraction. The analytical capabilities of the developed method are demonstrated on an example of determining lead in vegetable oils by atomic absorption spectrometry with electrothermal atomization. The limit of detection (3σ) for lead is 0.3 μg/kg. The developed method does not require sample mineralization.

Platinum (Pt)-based chemotherapy is the standard of care for muscle-invasive bladder cancer (MIBC). However, resistance is a major limitation. Reduced intratumoral drug accumulation is an important mechanism of platinum resistance. Our group previously demonstrated a significant correlation between tissue Pt concentration and tumor response to Pt-based neoadjuvant chemotherapy (NAC) in lung cancer. We hypothesized that increased Pt concentration in radical cystectomy (RC) specimens would correlate with improved pathologic response to Pt-based NAC in MIBC. A cohort of 19 clinically annotated, archived, fresh frozen RC specimens from patients with MIBC treated with Pt-based NAC was identified [ypT0 (pathologic complete response, pCR), N = 4; ≤ypT1N0M0 (pathologic partial response, pPR), N = 6; ≥ypT2 (minimal pathologic response/progression), N = 9)]. RC specimens from 2 patients with MIBC who did not receive NAC and 1 treated with a non-Pt containing NAC regimen were used as negative controls. Total Pt concentration in normal adjacent urothelial tissue and bladder tumors from RC specimens was measured by flameless atomic absorption spectrophotometry. Total Pt concentration in normal urothelium differed by tumor pathologic response (P = 0.011). Specimens with pCR had the highest Pt concentrations compared to those with pPR (P = 0.0095) or no response/progression (P = 0.020). There was no significant difference in Pt levels in normal urothelium and tumor between pPR and no response/progression groups (P = 0.37; P = 0.25, respectively). Our finding of increased intracellular Pt in RC specimens with pCR following NAC for MIBC compared to those with residual disease suggests that enhanced Pt accumulation may be an important determinant of Pt sensitivity. Factors that modulate intracellular Pt concentration, such as expression of Pt transporters, warrant further investigation as predictive biomarkers of response to Pt-based NAC in MIBC.

Heavy metals are one of the most hazardous inorganic contaminants of both water and soil environment composition. Normally, heavy metals are non-biodegradable in nature because of their long persistence in the environment. Trace amounts of heavy metal contamination may pose severe health problems in human beings after prolonged consumption. Many instrumental techniques such as atomic absorption spectrophotometry, inductively coupled plasma-mass spectrometry, X-ray fluorescence, neutron activation analysis, etc. have been developed to determine their concentration in water as well as in the soil up to ppm, ppb, or ppt levels. Recent advances in these techniques along with their respective advantages and limitations are being discussed in the present paper. Moreover, some possible remedial phytoremediation approaches (phytostimulation, phytoextraction, phyotovolatilization, rhizofiltration, phytostabilization) have been presented for the removal of the heavy metal contamination from the water and soil environments.

Development of single-atomic-site catalysts with high metal loading is highly desirable but proved to be very challenging. Although utilizing defects on supports to stabilize independent metal atoms has become a powerful method to fabricate single-atomic-site catalysts, little attention has been devoted to cation vacancy defects. Here we report a nickel hydroxide nanoboard with abundant Ni 2+ vacancy defects serving as the practical support to achieve a single-atomic-site Pt catalyst (Pt 1 /Ni(OH) x ) containing Pt up to 2.3 wt% just by a simple wet impregnation method. The Ni 2+ vacancies are found to have strong stabilizing effect of single-atomic Pt species, which is determined by X-ray absorption spectrometry analyses and density functional theory calculations. This Pt 1 /Ni(OH) x catalyst shows a high catalytic efficiency in diboration of a variety of alkynes and alkenes, yielding an overall turnover frequency value upon reaction completion for phenylacetylene of ~3000 h −1 , which is much higher than other reported heterogeneous catalysts. Development of single-atomic-site catalysts with high metal loading remains a challenge. Here, the authors report a nickel hydroxide nanoboard with abundant Ni 2+ vacancy defects serving as the support to achieve high platinum loading by simple wet impregnation.

The contents of lead, cadmium, chromium, copper, and nickel were determined in 25 tea samples from China, including green, yellow, white, oolong, black, Pu'er, and jasmine tea products, using high-resolution continuum source graphite furnace atomic absorption spectrometry. The methods used for sample preparation, digestion, and quantificational analysis were established, generating satisfactory analytical precisions (represented by relative standard deviations ranging from 0.6% to 2.5%) and recoveries (98.91–101.32%). The lead contents in tea leaves were 0.48–10.57 mg/kg, and 80% of these values were below the maximum values stated by the guidelines in China. The contents of cadmium and chromium ranged from 0.01 mg/kg to 0.39 mg/kg and from 0.27 mg/kg to 2.45 mg/kg, respectively, remaining in compliance with the limits stipulated by China's Ministry of Agriculture. The copper contents were 7.73–63.71 mg/kg; only 64% of these values complied with the standards stipulated by the Ministry of Agriculture. The nickel contents ranged from 2.70 mg/kg to 13.41 mg/kg. Consequently, more attention must be paid to the risks of heavy metal contamination in tea. The quantitative method established in this work lays a foundation for preventing heavy metal toxicity in human from drinking tea and will help establish regulations to control the contents of heavy metals in tea.

The paper considerations of the possibility of the low-temperature (1000°C) and high-temperature (>1500°C) thermal decomposition of solid samples of suspensions and the selective fractional evaporation–condensation of elements in specialized electrothermal crucible and rod atomizers for the purposes of direct atomic-absorption analysis. The approach is applied to analyze samples of riverine and marine suspensions for Ag, Cd, and Tl.

Water pollution caused by the discharge of hazardous textile effluents is a serious environmental problem worldwide. In order to assess the pollution level of the textile effluents, various physico-chemical parameters were analyzed in the textile wastewater and agricultural soil irrigated with the wastewater (contaminated soil) using atomic absorption spectrophotometer and gas chromatography-mass spectrometry (GC-MS) analysis that demonstrated the presence of several toxic heavy metals (Ni, Cu, Cr, Pb, Cd, and Zn) and a large number of organic compounds. Further, in order to get a comprehensive idea about the toxicity exerted by the textile effluent, mung bean seed germination test was performed that indicated the reduction in percent seed germination and radicle-plumule growth. The culturable microbial populations were also enumerated and found to be significantly lower in the wastewater and contaminated soil than the ground water irrigated soil, thus indicating the biotic homogenization of indigenous microflora. Therefore, the study was aimed to develop a cost effective and ecofriendly method of textile waste treatment using native soil bacterium, identified as Arthrobacter soli BS5 by 16S rDNA sequencing that showed remarkable ability to degrade a textile dye reactive black 5 with maximum degradation of 98% at 37 °C and pH in the range of 5–9 after 120 h of incubation.

Detection and quantification of heavy metals in soil samples are significant in terms of environmental monitoring and risk assessment for metals. In order to improve the accuracy and precision to detect heavy metal, in this study, four standard samples (NASS-4, NASS-5, NASS-9, and NASS-16) were analyzed by evolving heating (electric heating plate, water bath, and microwave) and acidic systems (includes HCl, HNO 3 , HF, and HClO 4 ). The result shows that different pretreatment methods have different effects on the extraction of heavy metal elements and five heavy metal elements (Cu, Zn, Pb, Ni, and Cr) were selected for optimization through pretreatment methods. Although the contents of heavy metals were same but we found diversity in the results. Under optimal conditions, the selected standard samples were analyzed by inductively coupled plasma mass spectrometry (ICP-MS), inductively coupled plasma atomic emission spectroscopy (ICP-AES), and atomic absorption spectroscopy (AAS), and the results were compared. The results show that different elements have their own most suitable detection methods, such as for Pb, the most suitable method is ICP-MS; and for Zn, the most suitable method is AAS. Pretreatment methods and detection techniques are combined to find and improve accuracy of results for certain elements. This study provides a reliable detection method for the accurate detection of heavy metals in the environment.

The work examines the determination of gold from environmental samples by dispersive liquid–liquid microextraction (DLLME) method. The method was developed for the separation and determination of Au (III) ions after chelating with bis (salicylaldehyde) ethylenediimine (H 2 SA 2 en) Schiff-base as derivatizing reagent. Flame atomic absorption spectrometry (FAAS) and inductively coupled plasma-optical emission spectrometry (ICP-OES) techniques were used for quantitation of Au (III). These techniques are sensitive and rapid for the determination of gold concentrations in ore, water and sediment samples. The influence of factors such as pH, reagent concentration, solvents (extracting) (disperser) and solvent volumes on extraction efficiency of Au (III) ions were studied and optimized by univariate and multivariate techniques. The linearity of the method was in the range of 2 to 12 µg/L with R 2  = 0.997. The limit of detection was 1 µg/L, and the limit of quantification was 3 µg/L. The preconcentration factor and enrichment factor values were 44 and 47. The repeatability (the intra-day) and reproducibility (the inter-day) precisions ( n  = 3) were found to be 0.417–3.56%. The proposed method was successfully applied for the determination of gold in sediment samples of the Indus River, Kori Barrage, goldsmith water, acidic solution of goldsmith and ornament samples collected from Goldsmith Labs and shops. The results found from FAAS were compared with those obtained from ICP-OES technique, and a good correlation with comparable selectivity and sensitivity was specified.

The quantification of harmful elements in cannabis is a relevant analytical task that requires metrological tools to ensure the reliability of the measurement results. This work reports the preparation and characterization of a certified reference material (CRM) for toxic elements—arsenic (As), cadmium (Cd), and lead (Pb)—in pulverized, lyophilized cannabis leaf tissue. To prepare the CRM INM-040-1, a portion of dried ground cannabis vegetal material was spiked with the elements at mass fraction values close to the levels of interest in relevant regulations for this kind of matrix: 0.34 mg/kg for arsenic, 0.34 mg/kg for cadmium, and 0.66 mg/kg for lead. The elements were quantified by inductively coupled plasma mass spectrometry (ICP-MS) in combination with graphite furnace atomic absorption spectroscopy (GF-AAS, for cadmium and lead) or hydride generation atomic absorption spectroscopy (HG-AAS, for arsenic). The analytical calibration was done by gravimetric standard addition for ICP-MS and GF-AAS, while bracketing calibration was used for HG-AAS. Furthermore, internal standard correction was used during ICP-MS measurements. The analytical methods were validated to demonstrate their fitness for purpose. The preparation variables of the CRM (particle size, drying treatment, and spiking conditions) were studied to improve the homogeneity of the CRM. The mass fraction of the toxic elements was certified with relative standard uncertainties ranging from 4.2 to 6.9%. The uncertainty contributions considered were the elements’ mass fraction measurements, the between-methods bias, the (in)homogeneity of the production batch, and the (in)stability under transport and storage conditions. This new CRM constitutes a useful tool for the laboratories assessing the harmlessness of cannabis materials, promoting humans’ safety and regulatory compliance within the medicinal cannabis industry. Graphical Abstract