Iodine radioisotopes, one of the major fission products in the nuclear industry, will cause widespread pollution due to their volatility when their inadvertent environmental release occurs. In this ...paper, a strategy for the efficient capture and real-time detection of iodine by amine-functionalized fluorescent conjugated mesoporous polymers (CMPs) is developed. CMPs are built up through a rigid skeleton and different flexible binding sites for iodine by the Sonogashira–Hagihara coupling reaction. Among them, CMP with N , N -diethylpropylamine (CMPN) shows outstanding capture ability for iodine vapor and dissolved iodine and also exhibits excellent stability against β- or γ-ray irradiation. Moreover, owing to the fluorescence quenching amplification of the conjugation skeleton, a CMPN-coated test paper enables highly sensitive detection of iodine even at 4 °C with a low vapor pressure of 16.8 Pa. To the best of our knowledge, CMPN with flexible and rigid binding sites gives the highest uptake values for iodine among all CMP-based materials reported to date, and it is the first functional material exhibiting the simultaneous adsorption and field detection of iodine vapor.
Uranium is one of the most important elements in the nuclear industry, but it also causes potential health risks to human beings when released into the natural environment. It is highly desired to ...develop a strategy that enables concurrent uranium detection and adsorption for sustainable development of nuclear energy and environmental conservation. In this work, a fluorescent conjugated microporous polymer consisting of 1,3,5-triethynylbenzene and amidoxime/carboxylate-substituted fluorene (CMPAO) is designed and synthesized for efficient extraction and detection of uranyl ions. The amidoxime ligands on CMPAO provide selective uranium-binding properties, while hydrophilic carboxylate groups largely enhance aqueous dispersibility leading to adequate contact with uranyl ions. As a consequence, CMPAO is capable of selective and efficient extraction of uranyl ions, achieving an optimal sorption capacity of 251.9 mg U g −1 . Moreover, the adsorption of uranium on CMPAO leads to dramatic fluorescence quenching, allowing selective and sensitive detection of uranyl ions by fluorescence spectroscopy. Importantly, thanks to the signal amplification by the conjugated skeleton, CMPAO has a fairly low detection limit of 1.7 × 10 −9 M for uranyl ions in deionized water, which is far below the maximum contamination standard in drinking water of the World Health Organization (6.3 × 10 −8 M).
The development of highly sensitive and selective uranyl ion (UO22+) probes has attracted significant attention owing to the threat to human health caused by high toxicity, radioactivity, and long ...half‐life. Herein, the development of aggregation‐induced emission (AIE) active polymer dots (Pdots) is described for an accurate UO22+ monitoring using a portable electrochemiluminescence (ECL) system. An AIE‐active polymer containing tetraphenylethene and boron ketoiminate moieties is prepared into Pdots and modified with ssDNA to capture UO22+, which can amplify the ECL signal of the Pdots through a resonance energy transfer mechanism. This probe provides an ultralow detection limit of 10.6 pm/2.5 ppt, which is at least two orders of magnitude lower than the known UO22+ luminescent probes. Only UO22+ can provide an obvious ECL enhancement among the various metal ions, indicating the excellent selectivity of this probe. Furthermore, a portable ECL analyzer is designed to realize UO22+ measurements in the wild. The anodic ECL mechanism of UO22+ is discovered and ECL technology is first applied in monitoring radioactive substances. This study provides a novel strategy for the development of accurate UO22+ probes and a practical UO22+ monitoring method, indicating its potential application in the environmental and energy fields.
A strategy is developed for the application of accurate trace UO22+ monitoring in the wild in both the energy and environmental fields. An ultralow limit of detection of 10.6 pm/2.5 ppt and high selectivity toward UO22+ is given in this study by using a portable electrochemiluminescence system and aggregation‐induced emission‐active polymer dot based “turn on” probe.
Recovery of uranium from high-level liquid wastes (HLWs) is of vital importance for sustainable nuclear energy. However, inherent high acidity, strong radioactivity and massive nuclear fission ...products are the major challenges for efficient extraction of uranium from HLWs. In this work, a new approach is reported for potential uranium extraction from HLWs using conjugated microporous polymers (CMPs) bearing ethylphosphate ligands (CMP-EP) as sorbents. CMP-EP with a BET surface area of 58.2 m 2 g −1 is prepared by the Suzuki coupling reaction of 1,3,5-tris(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)benzene and 2,7-dibromo-9,9′-bis(diethyl propylphosphonate)fluorene. HRTEM and SEM characterization shows that CMP-EP sheets possess an overlapping flaky morphology. The uranium sorption arises inside the pores of the material as confirmed by depth-profiling XPS of CMP-EP before and after adsorption. CMP-EP exhibits excellent binding selectivity for uranium( vi ) ions with a high sorption capability of 73 mg U per g in 6 M HNO 3 solutions, and outstanding reusability for adsorption when regenerated with alkaline solutions. Thanks to its rigid π-conjugated skeleton, the CMP-EP after γ-ray irradiation of 1000 kGy in 6 M HNO 3 shows no dramatic changes in structure, sorption capacity and selectivity. The sorption mechanism is studied by XPS and FTIR measurements revealing that uranyl ions tend to form complexes such as UO 2 (NO 3 ) 2 in 6 M HNO 3 , and then bind to PO groups of phosphonate ligands. This work represents the first example for effective recovery of uranium from HLWs using functional CMPs as sorbents.
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•A strategy is developed for efficient adsorption of broad-spectrum radionuclides.•The adsorbent of MoS2 sheet is functionalized with phosphonate and carboxyl groups.•There are large ...capacities of 448.4 mg U/g and 171.2 mg Eu/g for the adsorbents.•The sorption involves the interaction between multiple groups and uranium/europium.•This adsorbent is promising for the radionuclide separation in wastewater treatment.
It is significant to develop novel materials and techniques for efficient removal of radionuclides from radioactive wastes due to the radioactive and chemical toxicity. In this paper, we report a strategy for broad-spectrum adsorption of radionuclides by multiple groups-decorated adsorbents. Specifically, the adsorbents were prepared by grafting diethyl-(4-vinylbenzyl) phosphonate and maleic anhydride copolymers onto molybdenum disulfide sheets for the sorption of uranium(VI) and europium(III). The sorption efficiencies exhibited a dependency on pH, contact time and initial concentrations. The sorption reached the equilibrium within 60 min and followed a pseudo-second-order kinetic model. The maximum sorption capacities of the sorbents were 448.4 mg/g and 171.2 mg/g at pH 4.0 and 298.15 K for uranium(VI) and europium(III), respectively. The sorbent possessed a high efficiency of 98% in five sorption-desorption cycles without damage in chemical structures. XPS spectra showed that the sorption of uranium(VI) and europium(III) on the sorbents were originated from the interaction between multiple groups (such as sulfur, COOH, PO and PO) and uranium/europium. This work demonstrates that the adsorbent can be utilized as a promising material for the separation of broad-spectrum radionuclides from an aqueous solution.
A novel adsorbent for antibiofouling and highly selective uranium recovery from seawater is developed in this work. Specifically, the polypropylene nonwoven fabric modified with oxime and guanidine ...was obtained by subsequent radiation-grafting, ring-opening and oximation reaction. The adsorbent demonstrates outstanding selectivity for uranium(VI) against other competing metal ions in real seawater. The antibacterial assay indicated the adsorbent has good antibacterial properties against
Escherichia coli and Staphylococcus aureus
. XPS spectra indicate that uranium(VI) is adsorbed on the non-woven through the interaction with multiple groups. This work shows that the sorbent may be a hopeful material for the extraction of uranium from seawater.
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High‐dose ionizing radiation can lead to death from the unrecoverable damage of the gastrointestinal tract, especially the small intestine. Until now, the lack of predilection for the small intestine ...and rapid clearance by digestive fluids limit the effects of conventional radioprotective formulations. Herein, an innovative radioprotective strategy is developed for attenuating gastrointestinal syndrome by smart oral administration nanodrugs. The nanodrug is first engineered by encapsulating thalidomide into chitosan‐based nanoparticles, and then coated with polydopamine. The behaviors of gastric acid‐resistance, and pH‐switchable controlled release in the small intestine enhance the oral bioavailability of the pyroptosis inhibitor thalidomide. In a mouse model, nanodrugs demonstrate prolonged small intestinal residence time and accessibility to the crypt region deep in the mucus. Furthermore, the nanodrugs ameliorate survival rates of C57BL/6J mice irradiated by 14 Gy of subtotal body irradiation and also maintain their epithelial integrity. This work may provide a promising new approach for efficiently attenuating lethal radiation‐induced gastrointestinal syndrome and add insights into developing nanodrug‐based therapies with improved efficacy and minimum side effects.
An innovative radioprotective strategy is developed for attenuating gastrointestinal syndrome by smart orally administered nanodrugs. The nanodrugs exhibit gastric acid resistance, accessibility for small intestinal crypt, and prolonging residence time, which help to deliver the vast majority of the payload to the vulnerable crypt, thus enhancing the radioprotective effects. This work may provide a promising radioprotective countermeasure for either accidental or deliberate radiation exposure.
Nowadays, theranostics drug delivery systems (DDSs) with imaging and therapy bi-functions have been regarded as a future orientation for imaging-guided cancer therapy. To achieve high imaging ...quality, a donor–acceptor (D–A)/Förster resonance energy transfer (FRET) bi-adjustment strategy is carried out for designing dual-colored DDSs with amplified aggregation-induced emission (AIE) behavior for imaging-guided cocktail cancer therapy in this study. In detail, four AIE-active conjugated polymers P-1 to P-4 are synthesized via the Suzuki reaction. Noteworthily, the D–A-type structure is applied in tuning the fluorescence color from orange (P-1) to far-red/near-infrared (P-2), while the intramolecular FRET process further enhanced the fluorescence signal for six times (P-3). Afterwards, P-3-based amphipathic polymer P-4 further acts as a drug carrier in preparing doxorubicin (Dox)- and curcumin (Cur)-loaded polymer dots (Pdots) (Dox-loaded Pdots as PDox and Cur-loaded Pdots as PCur). PDox + PCur DDS is successfully applied in imaging-guided cocktail cancer therapy to give obviously higher in vivo anticancer efficacy compared with single PDox or PCur. In addition, the drug-loaded Pdots also exhibit higher biocompatibility compared with free drugs. This work provides a novel D–A/FRET bi-adjustment strategy for developing high efficiency imaging-guided cocktail DDSs in cancer therapy.
The worldwide application of nuclear power has created the potential risk of a nuclear accident, which has been a challenge to public security. In nuclear leakages, I 2 radioisotopes would cause ...rapid, global pollution. Therefore, highly sensitive and selective I 2 sensors exhibit their significance in nuclear accident early warnings and treatments. Herein, a conjugated polymer was developed for I 2 vapor monitoring with an ultra-low limit of detection (LOD). This polymer, modified with a tertiary amine as a co-reactive group, exhibits aggregation-induced electrochemiluminescence (AIECL) and self-enhanced ECL behaviors. It is noteworthy that the tertiary amine also acts as I 2 vapor capturing and sensing groups to give a LOD of 0.13 ppt. Excellent selectivity was obtained in various interfering atmospheres. A new mechanism was discovered for designing vapor sensors, which is summarized as co-reactive group poisoning (CGP). To meet the high efficiency requirement of nuclear emergency monitoring, an I 2 sensor modified screen printed carbon electrode was used due to its low cost, lack of need for pretreatment and suitability for mass production. A matching upwardly photosensitive ECL dark box was further designed. This study reports ECL vapor monitoring for the first time and provides a novel strategy for early warning of a nuclear emergency, suggesting its significance in environmental and public security fields.
It is of strategic importance to capture uranium( vi ) from aqueous solutions from the points of environment and energy. A new method is reported herein for efficient uranium( vi ) capture from ...aqueous solutions by amidoximated poly(vinyl imidazole)-functionalized MoS 2 sheets. Specifically, the sorbent is prepared by grafting amidoximated poly(vinyl imidazole) onto MoS 2 -sheets through covalent bonds. The sorption follows pseudo-second-order kinetics and the equilibrium can be reached within 30 s. There is a large sorption capacity of 348.4 mg g −1 at pH 8.0 and 298.15 K. The sorbent shows good selectivity towards uranium( vi ) over the coexisting ions in comparison with bare MoS 2 -sheets. In addition, the sorbent exhibits remarkable salt-resistant stability and can be regenerated efficiently after five cycles with high cycle efficiency. To the best of our knowledge, this is the first report on MoS 2 sheets for uranium( vi ) sorption with high efficiency from aqueous solution.
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