Efficient Purification Method Research Articles

Isolation of native EVs from primary biofluids—Free‐flow electrophoresis as a novel approach to purify ascites‐derived EVs

AbstractAlthough extracellular vesicles (EVs) have been extensively characterized, efficient purification methods, especially from primary biofluids, remain challenging. Here we introduce free‐flow electrophoresis (FFE) as a novel approach for purifying EVs from primary biofluids, in particular from the peritoneal fluid (ascites) of ovarian cancer patients. FFE represents a versatile, fast, matrix‐free approach for separating different analytes with inherent differences in charge density and/or isoelectric point (pI). Using a series of buffered media with different pH values allowed us to collect 96 fractions of ascites samples. To characterize the composition of the individual fractions, we used state‐of‐the‐art methods such as nanoflow and imaging flow cytometry (nFCM and iFCM) in addition to classical approaches. Of note, tetraspanin‐positive events measured using nFCM were enriched in a small number of distinct fractions. This observation was corroborated by Western blot analysis and electron microscopy, demonstrating only minor contamination with soluble proteins and lipid particles. In addition, these gently purified EVs remain functional. Thus, FFE represents a new, efficient and fast method for separating native and highly purified EVs from complicated primary samples.

Radiochemical quality control of the radiopharmaceutical, 89SrCl2 produced in FBTR

89SrCl2 radiopharmaceuticals is mainly used for bone pain palliation in the cancer patients, is being produced in FBTR via 89Y(n, p)89Sr using yttria target. The irradiated yttria target is chemically processed in high pure quartz distilled nitric acid medium in hot cell facility, to avoid the corrosion of components of hotcell due to chloride ions while using HCl medium. Being ionic species, the purified 89Sr(II) cation in aqueous solution containing bulk nitrate and other trace anions, exists as SrXn species where X: F−, Cl−, Br−, NO3−, PO43− and SO42−, n: stoichiometric anion content. The aim of the manuscript is to standardise an efficient ultra-low level anion purification method (ppb range) for the conversion of SrXn to SrCl2 and estimate the residual anionic impurities as recommended by the appropriate source specifications for its medical application. Various methods were standardised for the removal of anions in the SrCl2 source produced by the above process which include evaporation, calcination, anion exchange column, cation exchange column as well as its combination with pre-concentration column of ion chromatography (IC) technique using 89Sr tracers as well as FBTR produced 89Sr solution. Assay of 89Sr and other anions including nitrate for the above study were accomplished using Cerenkov counting and ion chromatography respectively. Thus evaporation-calcination-column chromatography mode was finalised to obtain pure SrCl2 source free from nitrate and other anionic impurities. This is the first ever systematic study for the Radiochemical quality control of nca 89SrCl2 radiopharmaceutical produced in a fast reactor. This study also finds its application to any analytical lab as well as industry where there is a requirement of anion purification in the ppb level.

Extraction, structure characterization and biological activity determination of (S)-(-)-palasonin from Butea monosperma (Lam.) Kuntze seeds

Development of novel pesticides from natural products is an effective way to generate new insecticides. (S)-(-)-palasonin (PLN) is a natural compound from Butea monosperma (Lam.) Kuntze Seeds. The extraction process optimization, structural characteristics, and insecticidal activity of PLN are investigated in this study. Results show that extraction yields reach 0.668 ± 0.080 ‰ under the optimized extraction conditions: liquid-solid ratio of 10.4 mL/g, extraction temperature of 81.5 °C, and extraction time of 8.4 h. The yielded PLN structure was characterized by GC/MS, FT/IR NMR as well as X-ray single crystal diffraction. Notably, this is the first report of the single crystal structure of PLN. PLN exhibits the highest ingestion toxicity to Plutella xylostella (LC 50 : 10.72 mg L -1 at 48 h) and the highest contact toxicity to Periplaneta americana and Plutella xylostella (LD 50 : 0.08 μg/adult and 0.22 μg/larva). Moreover, PLN has high activity against the field-evolved multi-resistant strain of Plutella xylostella . We also found that PLN exerts an inhibitory effect (IC 50 : 1.79 μM) on the serine/threonine protein phosphatase type 5 (PP5c), and this inhibitory effect has a high correlation with insecticidal activity. PP5c is consequently proposed to be a crucial target of PLN. These results show that PLN has the potential to be developed as an innovative botanical insecticide for field control and management resistance of Plutella xylostella . Fig. Chemical structures and sources of (S)-(-)-palasonin and cantharidin. (a) Butea monosperma seeds and chemical structures of (S)-(-)-palasonin; (b) Meloidae insect and chemical structures of cantharidin. • An efficient extraction and purification method (S)-(-)-palasonin is provided. • (S)-(-)-palasonin has strong insecticidal activity against Plutella xylostella. • (S)-(-)-palasonin has the potential to manage the resistance of Plutella xylostella. • PP5c is a crucial target for (S)-(-)-palasonin to exert high insecticidal activity .

An Efficient Method of Expression and Purification of Amyloid-Beta (Aβ1-42) Peptide from E. coli.

Amyloid-beta (Aβ) aggregation into soluble oligomers and fibril formation are associated with Alzheimer's disease (AD) pathogenesis. Aβ1-42 is the major form of the Aβ peptide present in neuritic plaques and shown to be neurotoxic both in vivo and in vitro. However, understanding the mechanism of its toxicity, aggregation, and other biochemical properties is limited because of its difficult production (recombinant or synthetic) and irreproducibility issues attributed to batch-to-batch preparation differences. Chemically synthetic Aβ1-42 is now well established, but it always introduces up to 5% D-isomers along with its L-isomeric form, and thus it is not fruitful for biochemical/structural studies. Here, we optimized an efficient published method for expression and purification of Aβ1-42 upon overexpression in Escherichia coli (E. coli) that provides a satisfactory yield as well as minimizes the variability between batch preparations. With the present protocol, ~7-8mg/liter of unlabeled peptide and ~3.5-4mg/liter for 13C,15N-labeled (double-labeled) Aβ1-42 were obtained.

Technical note: an optimized method to isolate, purify, and differentiate satellite cells from broiler chicks.

Development and maintenance of healthy muscle fibers rely on the myogenic potential of satellite cells (SC), muscle stem cells that proliferate and differentiate to form myotubes. Satellite cells are indispensable for post-hatch muscle growth as well as muscle repair and regeneration when myofibers are damaged. Pectoralis major of young broiler chicks (5-d olds) is a readily available source of SC, which can be used in vitro to elucidate cellular and molecular mechanisms responsible for muscle growth and regeneration in broilers. Here, we optimized a method for efficient isolation, purification, and differentiation of SC, from young broiler chicks. This procedure includes a simple method that allows SC to be purified from other muscle cell types that can impede the fidelity of follow-on experiments, particularly highly sensitive measures such as RNAseq. The methods for culturing and differentiating SC into multinucleated myotubes were also optimized by testing serum types, concentrations, and the effects of chicken embryo extract. Using the isolation procedure, a highly pure SC population (94.6 ± 2.11% Pax7+) with high viability and yield was obtained, and their capacity to differentiate into myotubes was confirmed. Enrichment for SC and myogenic capacity were maintained through multiple passages and after cryopreservation. Analysis of gene expression over the first 48 h of differentiation confirmed that SC exhibited the expected molecular signature of myogenesis. Taken together, this method simplifies the ability to isolate and maintain a relatively pure population of SC with strong myogenic potential from young broiler chicks, and should support downstream applications for assessing the impact of nutrients, metabolites, and other physiological cues on muscle growth and development in broilers.

Treatment of slaughterhouse industry wastewater with ultrafiltration membrane and evaluation with life cycle analysis

Slaughterhouse wastewater is one of the most produced industrial wastewater in the world and has a high pollution potential, and this wastewater can cause a high level of polluting effect when it is given directly to river beds or sewage systems. Wastewater contains proteins, fats, carbohydrates in the treatment of blood, skin and feathers, which results in much higher biological oxygen demand (BOD) and chemical oxygen content (COD). The possibility of using ultrafiltration for slaughterhouse wastewater treatment was investigated. The results showed that ultrafiltration can be an efficient purification method. COD and BOD5 remova lefficiency is around 96% and 95%. In addition to these results, the Life Cycle Analysis (LCA) of the ultrafiltration system was also carried out. Accordingly, the effects of ultrafiltration system on human health, ecosystem quality, climate change and resources were calculated as 0,00000046 Disability-Adjusted Life Years (DALY), 0,134 PDFxm2yr, 0,336 kg CO2 eq and 6,937 MJ respectively. As a result of the study, it is thought that slaughterhouse wastewater can be used as irrigation water after passing through the ultrafiltration membrane due to the high content of N and P.

Proposal and application of a novel extraction and purification technology for juglone from Juglans mandshurica waste branches: Reverse micellar microemulsion combined with magnetic solid phase extraction

A reverse micellar microemulsion combined with magnetic solid phase extraction (RMM-MSPE) technology was developed for the extraction and purification of juglone from Juglans mandshurica. Reverse micellar microemulsion (RMM) (Tween 80: n-propanol: n-hexane: 0.05 mol/L KCl aqueous solution = 27:13.5:4.5:55; w/w/w/w) was used to extract juglone based on microwave. The optimum conditions were a pH of 5.6, a liquid-solid ratio of 20:1 (mL/g), temperature of 40 °C, time of 63 s, and power of 400 W. Graphene oxide/nano diamonds/ Fe3O4 (GO/ND/Fe3O4) was prepared as adsorbent and applied to purify juglone by magnetic solid-phase extraction (MSPE). The optimum adsorption conditions were time of 14 h, solid to liquid ratio of 30 mg/mL, pH of 5.5 and shaker speed of 200 r/min. Anhydrous methanol provided the best desorption of juglone and the optimum conditions were a desorption time of 16 h, pH of 8, and the solid-liquid ratio of 40 mg/mL. The purity of juglone was 69.08% and the recovery yield was 78.67%. RMM and GO/ND/Fe3O4 could be reused three times and eight times after the first use, respectively. The proposed RMM-MSPE is a green and efficient alternative method for extraction and purification of juglone.

Separation and purification of highly infectious enterovirus A71 particles using a strong anion-exchange column

Virions produced from cell culture is the primary source for production of formalin-inactivated whole virus vaccines for enteroviruses. EV-A71 particles produced from culture system comprise two major types, the immature/empty (E)-particle and the mature/full (F)-particle, which both exhibit low isoelectric point (pI) values but have distinct differences in infectivity and immunogenicity. Although EV-A71 particles can conventionally be separated into E-particle and F-particle using sucrose gradient ultracentrifugation, this procedure is cumbersome and difficult to put into practice for vaccine production. Methods based on ion-exchange chromatography have been exploited to improve the purification efficacy; however, none of them are capable of separating the E- and F-particles efficiently. In this study, we aimed to develop an approach to isolate and purify the highly immunogenic mature EV-A71 particles. By applying a step gradient elution procedure, we successfully isolated the viral structure protein VP0-cleaved particles of EV-A71 from a mixture of cultured viral solution using the Q-membrane anion-exchange chromatography. The elution started with 0.1x phosphate buffered saline (PBS) solution while increasing the percentage of 1x PBS containing 1M NaCl in sequential steps. By this procedure, the VP0-cleaved mature particles and VP0-uncleaved immature particles of EV-A71 could be separated into different fractions in Q-membrane with gradually increased NaCl concentration in elution buffer. The purified VP0-cleaved particles were shown to have characteristics equivalent to those of the highly infectious F-particles of EV-A71. The overall recovery rate for the mature EV-A71 particles by Q-membrane is 56% and its purity was shown to be equivalent to those isolated by the sucrose gradient ultracentrifugation. Our approach provides a simple and efficient purification method for recovering mature, highly infectious virus particles from the EV-A71 culture bulk.

GEM-PA-Based Subunit Vaccines of Crimean Congo Hemorrhagic Fever Induces Systemic Immune Responses in Mice.

The Crimean Congo Hemorrhagic Fever Virus (CCHFV) is a tick-borne bunyavirus of the Narovirus genus, which is the causative agent of Crimean Congo Hemorrhagic Fever (CCHF). CCHF is endemic in Africa, the Middle East, Eastern Europe and Asia, with a high case-fatality rate of up to 50% in humans. Currently, there are no approved vaccines or effective therapies available for CCHF. The GEM-PA is a safe, versatile and effective carrier system, which offers a cost-efficient, high-throughput platform for recovery and purification of subunit proteins for vaccines. In the present study, based on a GEM-PA surface display system, a GEM-PA based vaccine expressing three subunit vaccine candidates (G-GP, including G-eGN, G-eGC and G-NAb) of CCHFV was developed, displaying the ectodomains of the structural glycoproteins eGN, eGC and NAb, respectively. According to the immunological assays including indirect-ELISA, a micro-neutralization test of pseudo-virus and ELISpot, 5 μg GPBLP3 combined with Montanide ISA 201VG plus Poly (I:C) adjuvant (A-G-GP-5 μg) elicited GP-specific humoral and cellular immunity in BALB/c mice after three vaccinations via subcutaneous injection (s.c.). The consistent data between IgG subtype and cytokine detection, ELISpot and cytokine detection indicated balanced Th1 and Th2 responses, of which G-eGN vaccines could elicit a stronger T-cell response post-vaccination, respectively. Moreover, all three vaccine candidates elicited high TNF-α, IL-6, and IL-10 cytokine levels in the supernatant of stimulated splenocytes in vitro. However, the neutralizing antibody (nAb) was only detected in A-G-eGC and A-G-eGC vaccination groups with the highest neutralizing titer of 128, suggesting that G-eGC could elicit a stronger humoral immune response. In conclusion, the GEM-PA surface display system could provide an efficient and convenient purification method for CCHFV subunit antigens, and the G-GP subunit vaccine candidates will be promising against CCHFV infections with excellent immunogenicity.

Removal of photoredox catalysts from polymers synthesized by organocatalyzed atom transfer radical polymerization.

Organocatalyzed atom transfer radical polymerization (O-ATRP) is a method of producing polymers with precise structures under mild conditions using organic photoredox catalysts (PCs). Due to the unknown toxicity of PCs and their propensity to introduce color in polymers synthesized by this method, removal of the PC from the polymer product can be important for certain applications of polymers produced using O-ATRP. Current purification methods largely rely on precipitation to remove the PC from the polymer, but a more effective and efficient purification method is needed. In this work, an alternative purification method relying on oxidation of the PC to PC · + followed by filtration through a plug to remove PC · + from the polymer and removal of the volatiles was developed. A range of chemical oxidants and stationary phases were tested for their ability to remove PCs from polymers, revealing chemical oxidation by N-bromosuccinimide followed by a filtration through a silica plug can remove up to 99% of the PC from poly(methyl methacrylate). Characterization of the polymer before and after purification demonstrated that polymer molecular weight, dispersity, and chain-end fidelity are not signficantly impacted by this purification method. Finally, this purification method was tested on a range of dihydrophenazine, phenoxazine, dihydroacridines, and phenothiazine PCs, revealing the strength of the chemical oxidant must match the oxidation potential of the PC for effective purification.

Binding of Coxsackievirus A21 procapsids to immobilized glutathione depends on cell culture conditions during infection

A prototype strain of Coxsackievirus A21 (CVA21) is under clinical evaluation as an oncolytic virus immunotherapy. To improve scalability of the manufacturing process, an affinity chromatography purification method was developed using immobilized glutathione resin that captured infectious CVA21 virions from cell culture harvests with high recovery and impurity clearance. Unexpectedly, the binding of empty CVA21 procapsids depended on production cell culture conditions during infection including temperature, presence of serum in the media, and production cell line. At 37 °C and 2% serum during infection, procapsids flowed-through while infectious virions bound and were recovered at >95% yield in the chromatography elution. However, at sub-physiological temperature or after removal of serum at infection, both procapsids and mature virions bound and co-eluted from the immobilized glutathione ligand. This work may improve the understanding of CVA21 capsid assembly and presents an efficient purification method that may be applied to picornaviruses that interact with intracellular GSH.

Purification of human iPSC-derived cells at large scale using microRNA switch and magnetic-activated cell sorting.

SummaryFor regenerative cell therapies using pluripotent stem cell (PSC)-derived cells, large quantities of purified cells are required. Magnetic-activated cell sorting (MACS) is a powerful approach to collect target antigen-positive cells; however, it remains a challenge to purify various cell types efficiently at large scale without using antibodies specific to the desired cell type. Here we develop a technology that combines microRNA (miRNA)-responsive mRNA switch (miR-switch) with MACS (miR-switch-MACS) to purify large amounts of PSC-derived cells rapidly and effectively. We designed miR-switches that detect specific miRNAs expressed in target cells and controlled the translation of a CD4-coding transgene as a selection marker for MACS. For the large-scale purification of induced PSC-derived cardiomyocytes (iPSC-CMs), we transferred miR-208a-CD4 switch-MACS and obtained purified iPSC-CMs efficiently. Moreover, miR-375-CD4 switch-MACS highly purified pancreatic insulin-producing cells and their progenitors expressing Chromogranin A. Overall, the miR-switch-MACS method can efficiently purify target PSC-derived cells for cell replacement therapy.

Direct degradation of methylene blue by unactivated peroxymonosulfate: reaction parameters, kinetics, and mechanism.

Advanced oxidation processes (AOPs) are efficient methods for water purification. However, there are few studies on using peroxymonosulfate (PMS) to remove pollutants directly. In this study, about 76% of methylene blue (MB) was removed by PMS directly within 180min through a non-radical pathway, verified by scavenging tests, electron paramagnetic resonance and kinetic calculations. Additionally, the effects of PMS dosage, MB concentration, temperature, initial pH and competitive anions were determined. High PMS dosage, temperature and pH promoted MB degradation (from 76 to 98%) while MB concentration showed no effect on MB removal. Besides, MB degradation followed pseudo-first-order kinetic with rate constants of 0.0082 to 0.3912min-1. The second-order rate constant for PMS reaction with MB was 0.08M-1s-1 at pH 3-6, but increased dramatically to 4.68M-1s-1 at pH 10.50. Chlorine could be catalysed by PMS at high concentration Cl- and degradation efficiency reached 98% within 90min. High concentration of bicarbonate accelerated MB removal due to the high pH value while humic acid showed a marginal effect on MB degradation. Furthermore, TOC removal rate of MB in the presence of chloride reached 45%, whereas PMS alone caused almost no mineralisation. This study provides new insights into pollutant removal and an additional strategy for water purification.

Purification of zinc sulfate solutions from chloride ions using bismuth hydroxosulfate

ABSTRACT An efficient, simple and lowcost method for purification of zinc sulfate solutions from chloride ions by precipitation with bismuth hydroxosulfate BiOHSO4∙H2O was proposed. Chemical analysis, X-ray diffraction (XRD) and scanning electron microscopy (SEM) were employed to characterize the solid obtained. The studied parameters were reaction temperature, pH, concentrations of zinc sulfate and chloride, and the molar ratio between BiOHSO4∙H2O and chloride. Under optimal conditions, the chloride removal efficiency reached 94.5–95.8% and the residual concentration of Cl− in the purified solution was 65–85 mg/L, which meets the requirements for zinc electrolysis and allows the production of special high-grade zinc. Compared with the commonly used approaches, the method proposed has the advantages such as a higher degree of purification of zinc electrolyte, the short period of time required for the BiOCl precipitation (1 hour) and good filterability. Apart from that, the consumption of the precipitant is close to the stoichiometric molar ratio, which makes the purification process cost-effective.

Strain-tunable self-passivated porous phosphorene for high-efficiency helium separation

The skyrocketing demand for helium (He) has stressed the limitation of the global He storge. The helium-rich natural gas represents the most accessible resource of He, thus the development of effective ways to extract He from natural gas is of high priority on the research agenda. The membrane-based separation technique is regarded as a promising method for efficient He purification that might possibly mitigate the current He shortage. In this work, by employing first-principles calculations together with molecular dynamics simulations, we predicted that both the strained and unstrained self-passivated porous phosphorene membrane can be used for efficient He harvest from natural gas. The results demonstrate that the porous phosphorene exhibits high He selectivities (104–1018) over impure molecules (CO, N2, CO2, CH4) and high He permeance of 10−3 mol m−2 s−1 Pa−1 at 300 K, both far exceeding the industry standard. More importantly, the He permeance of the porous phosphorene can be effectively regulated under moderate strain along with high selectivity. Therefore, the porous phosphorene presented in this study is a robust and mechanically-controlled semipermeable membrane for efficient He purification that holds a great prospect in industrial application.

Separation of acetylferrocene from synthetic mixtures by countercurrent chromatography

The main product of acetylation of ferrocene was successfully separated and purified with high purity from synthetic mixtures by countercurrent chromatography using a selected biphasic solvent system. According to distribution performance of main product and reactant, a two-phase solvent system was selected by thin layer chromatography, in which the partition coefficient for each component was determined by HPLC. Then a two-phase solvent system consisting of petroleum ether/ethyl acetate/methanol/water (6:4:6:4, v/v) was selected. After acetylation reaction, 20 mg of synthetic mixture was subjected to countercurrent chromatography, yielding 2.1 mg of ferrocene and 8.7 mg of acetyl ferrocene with 96.6% and 97.4% purity. Results indicated that countercurrent chromatography is a very efficient method for separation and purification of target product from synthetic mixtures.

Deciphering Precise Gene Transcriptional Expression Using gwINTACT in Tomato.

Functional gene transcription mainly occurs in the nucleus and has a significant role in plant physiology. The isolation of nuclei tagged in specific cell type (INTACT) technique provides an efficient and stable nucleus purification method to investigate the dynamic changes of nuclear gene transcriptional expression. However, the application of traditional INTACT in plants is still limited to seedlings or root cells because of severe chloroplast pollution. In this study, we proposed a newly designed and simplified INTACT based on mas-enhanced GFP (eGFP)-SlWIP2 (gwINTACT) for nuclear purification in tomato (Solanum lycopersicum) leaves, flowers, and fruits for the first time. The yield of the nucleus purified using gwINTACT from transgenic tomato leaves was doubled compared with using a traditional INTACT procedure, accompanied by more than 95% removal of chloroplasts. Relative gene expression of ethylene-related genes with ethylene treatment was reevaluated in gwINTACT leaves to reveal more different results from the traditional gene expression assay based on total RNA. Therefore, establishing the gwINTACT system in this study facilitates the precise deciphering of the transcriptional status in various tomato tissues, which lays the foundation for the further experimental study of nucleus-related molecular regulation on fruit ripening, such as ChIP-seq and ATAC-seq.

Rapid and Gentle Immunopurification of Brain Synaptic Vesicles.

Current methods to isolate synaptic vesicles (SVs), the organellar quanta of synaptic transmission, require highly specialized materials and up to 24 h. These technical obstacles have thus far limited the study of SVs in models of synaptic function and pathophysiology. Here, we describe techniques for the rapid isolation of SVs by immunoprecipitation with widely available antibodies conjugated to magnetic beads. We report that the inexpensive rho1D4 monoclonal antibody binds SVs and show that elution with the 1D4 peptide yields native vesicles that are ≥ 10-fold purer than those obtained with classical techniques. These methods substantially widen the accessibility of SVs, enabling their purification in 60–90 min for downstream analyses including mass spectrometry and cryo-electron microscopy. Immunopurified SV preparations from mouse brain contained apolipoprotein E, the LDL receptor Lrp1, and enzymes involved in lipid metabolism, suggesting that SVs may play direct roles in lipid homeostasis and lipoprotein trafficking at the nerve terminal.SIGNIFICANCE STATEMENT SVs are small organelles that form and recycle at nerve terminals to enable synaptic transmission. Much remains unknown about the processes that enable the formation and function of SVs. Moreover, nerve terminals appear to be particularly vulnerable to pathophysiologic processes underlying neurodegenerative diseases and schizophrenia. Although techniques to purify synaptic vesicles thus have the potential to yield significant insights into physiology and pathophysiology of nerve terminals, current methods rely on either esoteric materials or expression of transgenes. This article addresses these problems by establishing robust, efficient methods for SV purification using widely available materials, and it highlights several promising areas of future study arising from proteomic analyses of immunopurified SVs.

Self-assembling fluorescent hydrogel for highly efficient water purification and photothermal conversion

• The sulfydryl-based CDs (CDs-SH) displayed a selective, sensitive detection towards Hg(II). • Cellulose hydrogel with CDs-SH was self-assembled for simultaneously detecting and removing Hg(II). • CDs-SH hydrogel showed over 98% uptake efficiency and good detection ability for Hg(II). • The exhausted absorbents were upcycled via in-situ sulfurization for solar steam generation. • High evaporation rate of 1.30 kg m −2 h −1 and efficiency of 88.3% was achieved under one sun irradiation. Employing fluorescent hydrogels for hazardous Hg(II) detection and removal is an efficient method for water purification. However, it remains challenging to establish a fluorescent system with low detection limit and high adsorption capacity that can readily be upcycled into a valuable material resource. Herein, we report on a fluorescent hydrogel with 0D sulfydryl-based carbon dots that are self-assembled with a 3D hydrogel network. The cellulose-based hydrogel exhibited good sensitivity for the detection of Hg(II) over a range from 0 to 40 µM with a limit detection of 3.0 × 10 -6 M. The adsorption experiments confirmed that the cellulose-based hydrogel exhibits good Hg(II) extraction capacity of over 662.25 mg g −1 at room temperature, and can effectively reduce the Hg concentration to attain acceptable levels that comply with industrial water standards (0.05 mg L -1 ). Subsequently, we used a facile strategy to convert the exhausted waste adsorbent by in-situ sulfurization into a suitable material for solar steam generation. The as-prepared upcycled aerogel evaporators exhibited excellent evaporation rates of ∼ 1.30 kg m −2 h −1 under one sun irradiation. These results not only provide a strategy for heavy metal ion recognition and adsorption, but also provide a route to recycle hazardous waste for seawater desalination.

Degradation of diclofenac sodium with low concentration from aqueous milieu through polydopamine-chitosan modified magnetic adsorbent-assisted photo-Fenton process

Given the widespread occurrence of low-concentration diclofenac sodium (DCFS) in the aquatic milieu, the development of an efficient and economical purification method is essential. Magnetic polydopamine-chitosan modified adsorbent (MPDA-CS) was successfully prepared by coating polydopamine-chitosan onto Fe3O4 nanoparticles in this study. The favorable adsorption performance towards DCFS was well demonstrated by regulating the solution to various pH values and initial concentrations of DCFS. Furthermore, the convincing fitting of pseudo-second-order model and intraparticle diffusion model suggested that the dominance of chemical processes and intraparticle diffusion. The specific adsorption mechanism was presumed to be the interaction between MPDA-CS and DCFS molecules, including electrostatic attraction, hydrogen bonding and aromatic stacking. Through regulating standing time in acidic solution, the integrated homogeneous and heterogeneous photo-Fenton system was employed to degrade adsorbed DCFS through dissolved and surfaced Fe(II)/Fe(III) of MPDA-CS, which achieved the waste utilization of dissolved iron ions with excellent degradation efficiency of 96.38% in 40 min. The adsorption-degradation efficiency of DCFS decreased slightly by 2.2% during the initial three cycles. This work presents an energy-efficient method for removing low-concentration DCFS by drawing on the strengths of adsorption and degradation.