A phosphonium ionic liquid conjugated magnetic graphitic carbon nitride nanocomposite: an effective sample pretreatment tool for selenium separation and determination.

We established an innovative and easy-to-use methodology for selenium (Se) extraction and determination from real water samples utilizing a magnetic nanocomposite adsorbent (MNC-SPE) aided by an inductively coupled plasma mass spectrometry (ICP-MS) approach. The MNC-SPE adsorbent was fabricated by hybridizing Fe3O4 nanoparticles on the surface of carbon nitride nanosheets (GCN NSs) that were coated with 1-hexyl-3-methylimidazolium hexafluorophosphate ionic liquid (P-IL). A variety of techniques were used to thoroughly analyze the structural and chemical characteristics of MNC-SPE, and appear to have a great number of diverse active surface functional units (imidazole ring and -NH3+). In order to optimize the key factors affecting the Se extraction, parameters including the adsorbent dosage, contact time, eluent type, eluent volume, eluent time, and reusability of adsorbent were extensively studied. The proposed approach was validated under the optimal reaction conditions, and it showed good linearity between 0.15 and 100 pg µL-1 with a significant R2 value (R2 = 0.9994) toward Se metal. Besides, the Se limit of detection (LOD) and limit of quantification (LOQ) are 0.063 pg µL-1 and 0.147 pg µL-1, respectively. Further, by utilizing tap and river water samples, the applicability of the validated method was tested; the approach showed high Se recovery values in the range of 87.6-115.5% for the spiked real-world samples and the interday and intraday precision (RSD%) values of the approach were 4.8% (n = 6). The MNC-SPE can be regenerated and reused for four consecutive extraction-desorption cycles by employing 0.5 M NaOH eluent.

Iron-engineered mesoporous biocarbon composite and its adsorption, activation, and regeneration approach for removal of paracetamol in water.

Three-dimensional multi-porous Iron Oxide/carbon (Fe2O3/C) composites derived from tamarind shell biomass were synthesized by a single-step co-pyrolysis technique and utilized for Paracetamol (PAC) dismissal in the combined adsorption, and advanced oxidation such as electrochemical regeneration techniques. The Fe2O3/C composites were prepared by different pyrolysis temperatures, and named as TS750 (without Fe2O3at 750 °C), MTS450 BCs (Low-450 °C), MTS600 BCs (Moderate-600 °C) and MTS750 BCs (high-750 °C), respectively. As-prepared Fe2O3/C composite was characterized by FE-SEM, XRD, BET, and XPS analysis. The specific surface area and the spatial interaction between the interlayers of Fe2O3 and C were significantly improved by increasing the pyrolysis temperatures from 450 to 750 °C, which improved the adsorption capacity of Fe2O3/C composites in terms of higher rate constants and chemisorption kinetics. The Pseudo-second-order kinetics model fitted in the adsorption test results of Fe2O3/C composites with the highest correlation co-efficiency. The Langmuir-isotherms model fitted in the adsorption test of the TS750 and MTS450 BCs. The Freundlich isotherms model is more fit with MTS600 and MTS750 BCs. Based on the isotherm results, the MTS750 BCs achieved 46.9 mg/g of maximum PAC adsorption capacity. The optimized MTS750 composites could be completely recovered by using an advanced electrochemical oxidation regeneration approach within 180 min. Also, with the adsorption and recovery process, the TOC removal rate improved to ∼79.4%. After the 6th cycle electrochemical oxidation process, the obtained results of the re-adsorption test showed the stabile adsorption activity of the sorbent material. The data outcomes herein propose that this type of combined adsorption and electrochemical approach will be useful in commercial water treatment plants.

Visible fluorescent sensing of Cu2+ ions in urine by reusable chitosan/l-histidine-stabilized silicon nanoparticles integrated thin layer chromatography sheet.

This study reports a facile approach for the fabrication of chitosan (CS, biopolymer)- and l-histidine (L-His, biomolecule)-stabilized self-assembled silicon nanoparticles (SiNPs) for sensing Cu2+ ions. Approached method yielded 3.8 ± 0.04 nm size CS/L-His-SiNPs particles, with high stability against harsh pH and temperature conditions. Besides, CS/L-His-SiNPs highly selective to Copper amongst different metal ions tested (Fe3+, Mg2+, Al3+, Cr3+, Cr6+, Cu2+, Mn2+, Cd2+, Pb2+, Zn2+, Hg2+, Ca2+, Li2+, Po42-, As3+, As5+). As compared to the blank-SiNPs (LOD = 96.49 ± 0.223 µM) and CS-SiNPs (LOD = 33.35 ± 1.004 µM); L-His ligand, enhanced the sensitivity of the CS/L-His-SiNPs toward Cu2+ with remarkable LOD value of 55.02 ± 0.42 nM. Applicability of CS/L-His-SiNPs was evaluated by coating CS/L-His-SiNPs on thin layer chromatography (TLC) sheets, CS/L-His-SiNPs-TLC sheets exhibited significant sensing capacity toward Cu2+ ions, with a detection range of 4.0-900 µM, making them suitable for on-site analysis of Cu2+ ions from both environmental and clinical samples. Finally, Cu2+ sensing practicality of CS/L-His-SiNPs-TLC sheets were challenged against real human urine samples. Expressively, CS/L-His-SiNPs-TLC sheets could be regenerated using ethylenediaminetetraacetic acid (EDTA), without losing their photostability, and can be reused further.

Treatment of heavy metals containing wastewater using biodegradable adsorbents: A review of mechanism and future trends.

The direct disposal of industrial effluents into the aquatic system is considered as a significant environmental hazard in many countries. Because of poisonous chemicals, substantial volumes of effluent release, as well as the lack of adequate of conventional treatment methodologies, industrial effluent treatment is extremely difficult. Numerous researchers have been interested in adsorption technology for its high efficiency of pollutant removal, low cost, and abundantly available adsorbent. Various adsorbent materials, both natural and modified form, have been widely used for the removal of toxic contaminants from industrial effluent. This paper highlights recent advancements in multiple modification types to functionalize the adsorbent material, resulting in higher adsorption capacity on various toxic pollutants. This review provides an overview of the adsorption mechanism and parameters (pH, adsorbent dosage, initial concentration, temperature and interaction time), which influencing the removal efficiency of adsorbents. Furthermore, this review compiles the desorption study to recover the adsorbent and improve the cycle's financial viability. This review provides a concise overview of the future directions and outlook in the framework of adsorbent application for industrial wastewater treatment.

Green sample pre-treatment technique coupled with UHPLC-MS/MS for the rapid biomonitoring of dietary poly-unsaturated (omega) fatty acids to predict health risks.

Polyunsaturated fatty acids (PUFAs) consumption indicates beneficial effects on cardiovascular disease (CVD) and physiological processes in humans. However, the inappropriate ratio of omega-(ω)-PUFA levels in human blood is considered as raising the risk of CVD. Therefore, monitoring dietary ω-FAs in human serum is vital for early diagnosis for individuals to predict CVD risk. This work reports a fast green sample pre-treatment protocol for sensitive and simultaneous monitoring of ω-3-FAs and ω-6-FAs in serum by novel in-syringe-based ultrasonication-assisted alkaline hydrolysis coupled with vortex-induced liquid-liquid microextraction (IS-USAH-VI-LLME) technique connected with UHPLC-MS/MS analysis. Factors affecting extraction recoveries of ten ω-PUFAs by the presented method were well-studied. ω-3 and ω-6 PUFAs demonstrated excellent linearities between the concentrations between 0.1-10,000 ng mL-1 with good regression coefficients between 0.9910-0.9997. The detection and quantification limits were between 0.05-0.35 and 0.16-1.07 ng mL-1, demonstrating that the presented method is highly sensitive and versatile. The precision of the technique was <8.2% that deemed acceptable in clinical analysis. Further, the proposed method was applied for ω-PUFAs analysis in human blood samples, and spiked recoveries showed between 80.32-119.34% with <9.82% precision. Results proved that the developed method is green, sensitive, and reliable to simultaneously determine ten ω-PUFAs in human blood samples for clinical diagnosis applications for predicting health hazards.

Rapid determination of remdesivir (SARS-CoV-2 drug) in human plasma for therapeutic drug monitoring in COVID-19-Patients.

To tackle the harmful consequences of the widespread COVID-19 pandemic, a broad-spectrum anti-viral drug remdesivir (RDV) has gained the utmost attention recently due to its promising application in treating COVID-19 patients. However, a fast and sensitive analytical methodology is important to monitor RDV drug profile in human plasma for pharmacokinetics (PK) and therapeutic drug monitoring (TDM). In this study, we demonstrate an improved vortex-assisted salt-induced liquid-liquid microextraction (VA-SI-LLME) technique coupled with UHPLC-PDA and UHPLC-MS/MS for rapid determination of RDV in human plasma. This technique involves simple one-step protein precipitation with hydrochloric acid and subsequent extraction with acetonitrile for analysis. Under the optimal VA-SI-LLME conditions (500 µL of acetonitrile with 2.5 g ammonium sulfate under 2 min vortex extraction), method validation results indicated an excellent correlation coefficient of 0.9969 for UHPLC-PDA (monitored at 254 nm) and 0.9990 for UHPLC-MS/MS (monitored at electrospray ionization with + ion mode transitions of m/z 603.1→m/z 402.20 and m/z 603.1→ m/z 199.90). The detection and quantification limits were 1.5 and 5 ng/mL for UHPLC/PDA, and 0.3 and 1 ng/mL for UHPLC-MS/MS, respectively. The developed method showed excellent extraction recoveries between 90.79-116.74 % and 85.68-101.34 % with intraday and interday precision ≤ 9.59 for both methods. These results proved that the developed method is a simple, fast, and sensitive analytical method that can be applied as a standard analytical tool for PK and TDM studies of RDV in clinical trials during the current worldwide outbreak.

Low-cost disposable Poly(ethyleneimine)-Functionalized Carbon Nanofibers Coated Cellulose Paper as efficient solid phase extraction sorbent material for the extraction of Parahydroxybenzoates from environmental waters.

Parahydroxybenzoates (parabens) are considered as emerging environmental contaminants because of their extensive usage in our daily life products, causing parabens contamination into environmental water systems and lead to toxic effects on environmental health. This study describes a greener extraction method using a new cationic polymer poly (ethyleneimine) functionalized acid-treated carbon nanofibers (PEI-CNFs) coated cellulose paper (CP) as solid-phase extraction (SPE) sorbent material for the extraction of parabens from environmental water samples. The fabrication of PEI-CNFs modified CP was confirmed using field-emission scanning electron microscope, transmission electron microscopy, and fourier-transformer infrared spectroscopy techniques. Various factors affecting the adsorption and desorption of parabens on PEI-CNFs@CP and its extraction efficiencies were studied using HPLC-UV analysis. Under the optimal experimental conditions, maximum extraction efficiencies were achieved for four target parabens, and PEI-CNFs@CP/HPLC-UV method exhibited excellent linearities ranged from 0.5-50 ng mL-1 with regression coefficient values were between 0.9952-0.9970. The presented method showed good sensitivity with quantification limits between 0.5-0.75 ng mL-1 and detection limits between 0.1-0.25 ng mL-1. The developed technique was applied for the real sample analysis (river, lake, domestic sewage water, and drinking tap water). The spiked recovery revealed good recoveries between 86.8-116.0% with RSD less than 8.8% for all the water samples. These results proved that it a simple, fast, efficient, low-cost, and eco-friendly method for the extraction and determination of parabens in environmental water samples and can be applied as a routine analytical tool in environmental monitoring and quality control laboratories.

Rapid and sensitive analytical procedure for biomonitoring of organophosphate pesticide metabolites in human urine samples using a vortex-assisted salt-induced liquid-liquid microextraction technique coupled with ultra-high-performance liquid chromatography/tandem mass spectrometry.

RATIONALE: Organophosphate pesticides (OPPs) are the most commonly used insecticides around the world in various agricultural and domestic practices, and humans are frequently exposed to these hazardous insecticides that can lead to several chronic health effects. Therefore, a fast and sensitive analytical method is required for biomonitoring the markers of OPPs in humans for exposure estimation. In this study, a fast and sensitive analytical procedure was developed for the determination of the metabolites of OPPs in human urine samples. METHODS: Metabolites of OPPs were extracted from 2 mL of urine sample using a novel vortex-assisted salt-induced liquid-liquid microextraction (VA-SI-LLME) technique, and the preconcentrated metabolites were analyzed by ultra-high-performance liquid chromatography/tandem mass spectrometry (UHPLC/MS/MS). Various factors affecting the efficiency of VA-SI-LLME were thoroughly investigated. RESULTS: The metabolites of OPPs exhibited very good linearity over the concentration range between 0.05 and 50 ng mL-1 with coefficient (r2 ) values ranging between 0.9986 and 0.9999. The method showed excellent sensitivity with detection limits ranging from 0.01 to 0.03 ng mL-1 and quantification limits from 0.03 to 0.05 ng mL-1 . The developed method was applied to the analysis of real samples and the recoveries ranged between 85.0 and 114.1% with related standard deviations <5%. CONCLUSIONS: The results showed the VA-SI-LLME/UHPLC/MS/MS method to be a simple, rapid, sensitive, and selective analytical procedure for the biomonitoring of the metabolites of OPPs in humans. This efficient and cost-effective analytical method could be a potential alternative method for the biomonitoring of the metabolites of pesticides in humans.