Cesium Removal from High Level Liquid Waste Utilizing a Macroporous Silica-based Calix[4]arene-R14 Adsorbent Modified with Surfactants

Abstract1,3-[(2,4-diethylheptylethoxy)oxy]-2,4-crown-6-Calix[4]arene(Calix[4]arene-R14) modified with dodecanol and dodecyl benzenesulfonic acid (DBS) was impregnated into the pores of macroporous silica-based polymer support (SiO2-P). The adsorbent was used to uptake Cs(I), Na(I), K(I), Sr(II), Pd(II), Ru(III), Y(III), La(III), Eu(III), Ce(III), Rh(III), Zr(IV), and Mo(VI) from HNO3 solution by batch technique. The leakage of total organic carbon (TOC) and dodecyl benzenesulfonic acid from the adsorbent into aqueous phase were below 60ppm and 0.51 wt% at 298K, 75ppm and 1 wt% at 318K in the range of 0.5 ∼ 5M HNO3, respectively. The adsorbent containing DBS presented a higher selectivity for Cs(I) compared to the DBS-free one. The Kd value of Cs(I) was about 3×103cm3/g at 0.5M HNO3. The adsorbent had almost no uptake for other tested metals in the range of 0.5 ∼ 7M HNO3

Amidoxime Functionalization of Algal/Polyethyleneimine Beads for the Sorption of Sr(II) from Aqueous Solutions

International audienceThere is a need for developing new sorbents that incorporate renewable resources for the treatment of metal-containing solutions. Algal-polyethyleneimine beads (APEI) (reinforced with alginate) are functionalized by grafting amidoxime groups (AO-APEI). Physicochemical characteristics of the new material are characterized using FTIR, XPS, TGA, SEM, SEM-EDX, and BET. AO-APEI beads are tested for the recovery of Sr(II) from synthetic solutions after pH optimization (≈ pH 6). Uptake kinetics is fast (equilibrium ≈ 60-90 min). Sorption isotherm (fitted by the Langmuir equation) shows remarkable sorption capacity (≈ 189 mg Sr g −1). Sr(II) is desorbed using 0.2 M HCl/0.5 M CaCl 2 solution; sorbent recycling over five cycles shows high stability in terms of sorption/desorption performances. The presence of competitor cations is studied in relation to the pH; the selectivity for Sr(II) is correlated to the softness parameter. Finally, the recovery of Sr(II) is carried out in complex solutions (seawater samples): AO-APEI is remarkably selective over highly concentrated metal cations such as Na(I), K(I), Mg(II), and Ca(II), with weaker selectivity over B(I) and As(V). AO-APEI appears to be a promising material for selective recovery of strontium from complex solutions (including seawater)

Nanoparticulation of Prodrug into Medicines for Cancer Therapy

This article provides a broad spectrum about the nanoprodrug fabrication advances co-driven by prodrug and nanotechnology development to potentiate cancer treatment. The nanoprodrug inherits the features of both prodrug concept and nanomedicine know-how, attempts to solve underexploited challenge in cancer treatment cooperatively. Prodrugs can release bioactive drugs on-demand at specific sites to reduce systemic toxicity, this is done by using the special properties of the tumor microenvironment, such as pH value, glutathione concentration, and specific overexpressed enzymes; or by using exogenous stimulation, such as light, heat, and ultrasound. The nanotechnology, manipulating the matter within nanoscale, has high relevance to certain biological conditions, and has been widely utilized in cancer therapy. Together, the marriage of prodrug strategy which shield the side effects of parent drug and nanotechnology with pinpoint delivery capability has conceived highly camouflaged Trojan horse to maneuver cancerous threats

Endovascular Metal Devices for the Treatment of Cerebrovascular Diseases

Cerebrovascular disease involves various medical disorders that obstruct brain blood vessels or deteriorate cerebral circulation, resulting in ischemic or hemorrhagic stroke. Nowadays, platinum coils with or without biological modification have become routine embolization devices to reduce the risk of cerebral aneurysm bleeding. Additionally, many intracranial stents, flow diverters, and stent retrievers have been invented with uniquely designed structures. To accelerate the translation of these devices into clinical usage, an in‐depth understanding of the mechanical and material performance of these metal‐based devices is critical. However, considering the more distal location and tortuous anatomic characteristics of cerebral arteries, present devices still risk failing to arrive at target lesions. Consequently, more flexible endovascular devices and novel designs are under urgent demand to overcome the deficiencies of existing devices. Herein, the pros and cons of the current structural designs are discussed when these devices are applied to the treatment of diseases ranging broadly from hemorrhages to ischemic strokes, in order to encourage further development of such kind of devices and investigation of their use in the clinic. Moreover, novel biodegradable materials and drug elution techniques, and the design, safety, and efficacy of personalized devices for further clinical applications in cerebral vasculature are discussed.Peer reviewe

A Phosphonic Functionalized Biopolymer for the Sorption of Lanthanum (III) and Application in the Recovery of Rare Earth Elements

Authors of the article state that in the first step of their experiment, the sorption was investigated using La(III) ions before testing for the recovery of rare earth elements (REEs) from pretreated industrial acidic leachate. They infer that phosphonate groups participate in the sorption, and that the most effective sorption is at pH = 4

Comprehensive evaluation of methods for small extracellular vesicles separation from human plasma, urine and cell culture medium

One of the challenges that restricts the evolving extracellular vesicle (EV) research field is the lack of a consensus method for EV separation. This may also explain the diversity of the experimental results, as co???separated soluble proteins and lipoproteins may impede the interpretation of experimental findings. In this study, we comprehensively evaluated the EV yields and sample purities of three most popular EV separation methods, ultracentrifugation, precipitation and size exclusion chromatography combined with ultrafiltration, along with a microfluidic tangential flow filtration device, Exodisc, in three commonly used biological samples, cell culture medium, human urine and plasma. Single EV phenotyping and density???gradient ultracentrifugation were used to understand the proportion of true EVs in particle separations. Our findings suggest Exodisc has the best EV yield though it may co???separate contaminants when the non???EV particle levels are high in input materials. We found no 100% pure EV preparations due to the overlap of their size and density with many non???EV particles in biofluids. Precipitation has the lowest sample purity, regardless of sample type. The purities of the other techniques may vary in different sample types and are largely dependent on their working principles and the intrinsic composition of the input sample. Researchers should choose the proper separation method according to the sample type, downstream analysis and their working scenarios

Mifepristone Increases the Cytotoxicity of Uterine Natural Killer Cells by Acting as a Glucocorticoid Antagonist via ERK Activation

Background: Mifepristone (RU486), a potent antagonist of progesterone and glucocorticoids, is involved in immune regulation. Our previous studies demonstrated that mifepristone directly augments the cytotoxicity of human uterine natural killer (uNK) cells. However, the mechanism responsible for this increase in cytotoxicity is not known. Here, we explored whether the increased cytotoxicity in uNK cells produced by mifepristone is due to either anti-progesterone or anti-glucocorticoid activity, and also investigated relevant changes in the mitogen-activated protein kinase (MAPK) pathway. Methodology/Principal Findings: Uterine NK cells were isolated from decidual samples and incubated with different concentrations of progesterone, cortisol, or mifepristone. The cytotoxicity and perforin expression of uNK cells were detected by mitochondrial lactate dehydrogenase-based MTS staining and flow cytometry assays, respectively. Phosphorylation of components of the MAPK signaling pathway was detected by Western blot. Cortisol attenuated uNK cell-mediated cytotoxicity in a concentration-dependent manner whereas progesterone had no effect. Mifepristone alone increased the cytotoxicity and perforin expression of uNK cells; these effects were blocked by cortisol. Furthermore, mifepristone increased the phosphorylation of ERK1/2 in a cortisol-reversible manner. Specific ERK1/2 inhibitor PD98059 or U0126 blocked cortisol- and mifepristone-induced responses in uNK cells

The Ninth Visual Object Tracking VOT2021 Challenge Results

acceptedVersionPeer reviewe

Quaternization of algal/PEI beads (a new sorbent): Characterization and application to scandium sorption from aqueous solutions

International audienceAlgal/Polyethyleneimine beads (APEI) were successfully quaternized to prepare an efficient sorbent (Q-APEI) for Sc(III) recovery. The functionalization has been confirmed by a series of analytical procedures: titration (pHPZC), elemental analysis, SEM, BET, EDX, FTIR, XPS and TGA. The sorption properties for Sc(III) from mild acidic solutions have been compared for APEI and Q-APEI: the sorption capacity increases from 1.0 to 3.8 mmol Sc g−1, at the optimum pH; (i.e., 4.5). The porous structure (specific surface area close to 34 m2 g−1) of the sorbent allows reaching the equilibrium within 60–90 min. Metal desorption is highly efficient using 0.5 M HCl/CaCl2 solutions; the sorbent can be recycled for at least 5 cycles with limited decrease in sorption capacity. FTIR and XPS analysis confirm the stability of the material though some chemical changes can be observed. The sorption mechanism involves different reactive groups associated with the diversity of functional sites: carboxylate groups (from alginate) and more specifically amine groups (from PEI and quaternary amine grafted moieties) with contribution of different scandium species (free or scandium sulfate complexes), depending on the pH. The sorbent is selective from Mg(II), Sm(III), Ca(II) and Na(I) (from equimolar synthetic solutions) at pH higher than 4. The application of Q-APEI for the sorption of Sc(III) from industrial solution (derived from red mud) shows that despite a high excess of iron, titanium or aluminum, scandium sorption is highly efficient (even at low metal concentration); though the sorbent is not selective

Study on the Effect of Gamma-Ray Irradiation on the Adsorption of ⁹⁹Tc and Re by a Silica-Based Pyridine Resin

A silica-based anion exchange resin was synthesized and used to remove 99Tc from real radioactive liquid waste. The adsorbent had a uniform particle size and exhibited good thermal stability up to 100 °C, which is promising for large-scale column experiments. In accordance with the chemical similarity with Tc, Re was used as a surrogate in this study. The N 1s high-resolution XPS spectra of the adsorbent before and after the adsorption of Re indicated that the ion exchange reaction was the controlling mechanism in the process. After γ-ray irradiation, the changing trend of the Kd was consistent, which showed that the competitive adsorption of NO3− led to a decrease in Kd. The adsorption capacity for the Re decreased slightly from 35.8 to 31.9 mg/g with the increase in the absorbed dose from 0 to 50 kGy. The separation and recovery of Re and the coexisting ions were achieved by chromatographic separation experiments, and the recovery percentage of Re was 86%. In real radioactive liquid waste, N3/SiO2 exhibited good selectivity toward 99Tc over the coexisting metals, namely, 90Sr, 137Cs, 241Am, and U, and the decontamination efficiency of 99Tc attained 65%