Fast Uptake Research Articles

BIRDIE: A data pipeline to inform wetland and waterbird conservation at multiple scales

IntroductionEfforts to collect ecological data have intensified over the last decade. This is especially true for freshwater habitats, which are among the most impacted by human activity and yet lagging behind in terms of data availability. Now, to support conservation programmes and management decisions, these data need to be analyzed and interpreted; a process that can be complex and time consuming. The South African Biodiversity Data Pipeline for Wetlands and Waterbirds (BIRDIE) aims to help fast and efficient information uptake, bridging the gap between raw ecological datasets and the information final users need.MethodsBIRDIE is a full data pipeline that takes up raw data, and estimates indicators related to waterbird populations, while keeping track of their associated uncertainty. At present, we focus on the assessment of species abundance and distribution in South Africa using two citizen-science bird monitoring datasets, namely: the African Bird Atlas Project and the Coordinated Waterbird Counts. These data are analyzed with occupancy and state-space models, respectively. In addition, a suite of environmental layers help contextualize waterbird population indicators, and link these to the ecological condition of the supporting wetlands. Both data and estimated indicators are accessible to end users through an online portal and web services.Results and discussionWe have designed a modular system that includes tasks, such as: data cleaning, statistical analysis, diagnostics, and computation of indicators. Envisioned users of BIRDIE include government officials, conservation managers, researchers and the general public, all of whom have been engaged throughout the project. Acknowledging that conservation programmes run at multiple spatial and temporal scales, we have developed a granular framework in which indicators are estimated at small scales, and then these are aggregated to compute similar indicators at broader scales. Thus, the online portal is designed to provide spatial and temporal visualization of the indicators using maps, time series and pre-compiled reports for species, sites and conservation programmes. In the future, we aim to expand the geographical coverage of the pipeline to other African countries, and develop more indicators specific to the ecological structure and function of wetlands.

Molecular Imprinting of Benzylpiperazine: A Comparison of the Self-Assembly and Semi-Covalent Approaches

Molecularly imprinted polymers (MIPs) for benzylpiperazine (BZP, 1), an illicit designer drug, were developed by using both self-assembly and semi-covalent approaches. From an array of potential functional monomers (FMs) and using a combination of pre-synthetic interaction studies (by molecular modelling and NMR analysis) and binding assays, the highest performing self-assembly 1-MIPs were confirmed to result from methacrylic acid (7) as FM, ethylene glycol dimethacrylate (EGDMA) or trimethylolpropane trimethacrylate (TRIM) as crosslinkers and chloroform as the porogen and rebinding solvent at template (T): FM ratios of 1:1 and 1:2, giving imprinting factors (IF) 3 to 7. The semi-covalent 1-MIPs were designed using benzylpiperazine (4-vinylphenyl) carbamate (16) as the template-monomer adduct in combination with either EDGMA or TRIM. Our comparative analysis showed the semi-covalent polymers to have a stronger affinity for 1 (significantly lower Kd values and higher IFs) and faster uptake than the self-assembly systems. Both approaches have comparable cross-reactivity: marginal to low against cocaine (17) and morphine (18) and high against ephedrine (19) and phenylpiperazine (20). They also have comparable selectivity: highly selective towards 1 against 17, moderate against 18 and non-selective against 19. EGDMA-based self-assembly MIPs displayed a greater imprinting effect (higher IFs and NIP-to-MIP Kd ratios) than TRIM-based MIPs, while the TRIM-based semi-covalent MIP outperformed its EGDMA-based equivalent. By virtue of its modest selectivity against the test illicit drugs, 1-MIPs could potentially be used as a dummy MIP for the broad-based capture and enrichment of illicit drug blends for subsequent laboratory analysis.

Removal of Low Trace ppb-Level Perfluorooctanesulfonic Acid (PFOS) with ZIF-8 Coatings Involving Adsorbent Degradation.

For the first time, low trace-level removal of perfluorooctanesulfonic acid (PFOS), i.e., 20-500 μg/L (ppb), from aqueous solutions using zeolitic imidazolate framework-8 (ZIF-8)-coated copper sheet (ZIF-8@Cu) composite is reported here. In comparison with different commercial activated carbon (AC) and all-silica zeolites, the composite showed the highest removal rate of 98%, which remained consistent over a wide range of concentrations. Additionally, no adsorbent leaching from the composite was noticed, which eradicated pre-analysis steps such as filtration and centrifugation, unless needed for other adsorbents studied here. The composite displayed fast uptake with saturation reaching within 4 h, irrespective of the initial concentration. However, the morphological and structural characterization revealed surface degradation of ZIF-8 crystals, along with a decline in the crystal size. The adsorption of PFOS on ZIF-8 crystals was linked to chemisorption, as the surface degradation surges with an increase in PFOS concentration or with cyclic exposure at low concentrations. Methanol seemingly removed surface debris (partially), thus providing access to ZIF-8 beneath the surface debris. Overall, the findings demonstrate that at low trace ppb-level PFOS concentrations ZIF-8 can be considered as a possible candidate for PFOS removal, even though it suffers slow surface degradation, it also removes efficiently PFOS molecules from aqueous solutions.

Lutetium177-Labeled DOTA-Ibandronate: A Novel Radiopharmaceutical for Targeted Treatment of Bone Metastases.

Bone metastases of malignant tumors significantly threaten the patient survival and quality of life. We designed and synthesized a novel bisphosphonate radiopharmaceutical [68Ga- or 177Lu-labeled DOTA-Ibandronate(68Ga/177Lu-DOTA-IBA)] for targeted diagnosis and treatment of bone metastases. This study explored the basic biological characteristics of 177Lu-DOTA-IBA, guiding clinical translation and providing evidence for future clinical applications. The control variable method was used to optimize the optimal labeling conditions. The in vitro properties, biological distribution, and toxicity of 177Lu-DOTA-IBA were studied. Normal mice and tumor-bearing mice were imaged using micro SPECT/CT. With Ethics Committee approval, five volunteers were recruited for a preliminary clinical translation study. 177Lu-DOTA-IBA has a radiochemical purity of more than 98%, with good biological properties and safety. Blood clearance is fast and soft tissue uptake is low. Tracers are excreted mainly through the urinary system, targeting and continuously concentrating in the bones. Three patients experienced significant pain relief within 3 days after 177Lu-DOTA-IBA treatment (740-1110 MBq), lasting more than 2 months, with no toxic side effects. 177Lu-DOTA-IBA is easy to prepare and exhibits good pharmacokinetic characteristics. Low-dose 177Lu-DOTA-IBA is effective, well tolerated, and was associated with no significant adverse reactions. It is a promising radiopharmaceutical for the targeted treatment of bone metastases, controlling the progress of bone metastasis and improving survival and quality of life of patients with advanced bone metastasis.

Facile Strategy for Fabricating an Organosilica-Modified Fe3O4 (OS/Fe3O4) Hetero-nanocore and OS/Fe3O4@SiO2 Core-Shell Structure for Wastewater Treatment with Promising Recyclable Efficiency.

The development of a sustainable process for heavy metal ion remediation has become a point of interest in various fields of research, including wastewater treatment, industrial development, and health and environmental safety. In the present study, a promising sustainable adsorbent was fabricated through continuous controlled adsorption/desorption processes for heavy metal uptake. The fabrication strategy is based on a simple modification of Fe3O4 magnetic nanoparticles with organosilica in a one-pot solvothermal process, carried out in order to insert the organosilica moieties into the Fe3O4 nanocore during their formation. The developed organosilica-modified Fe3O4 hetero-nanocores had hydrophilic citrate moieties, together with hydrophobic organosilica ones, on their surfaces, which facilitated the further surface coating procedures. To prevent the formed nanoparticles from leaching into the acidic medium, a dense silica layer was coated on the fabricated organosilica/Fe3O4 (OS/Fe3O4). In addition, the prepared OS/Fe3O4@SiO2 was utilized for the adsorption of cobalt(II), lead(II), and manganese(II) from the solutions. The data for the adsorption processes of cobalt(II), lead(II), and manganese(II) on OS/(Fe3O4)@SiO2 were found to follow the pseudo-second-order kinetic model, indicating the fast uptake of heavy metals. The Freundlich isotherm was found to be more suitable for describing the uptake of heavy metals by OS/Fe3O4@SiO2 nanoparticles. The negative values of the ΔG° showed a spontaneous adsorption process of a physical nature. The super-regeneration and recycling capacities of the OS/Fe3O4@SiO2 were achieved, comparing the results to those of previous adsorbents, with a recyclable efficiency of 91% up to the seventh cycle, which is promising for environmental sustainability.

AI explainability and governance in smart energy systems: A review

Traditional electrical power grids have long suffered from operational unreliability, instability, inflexibility, and inefficiency. Smart grids (or smart energy systems) continue to transform the energy sector with emerging technologies, renewable energy sources, and other trends. Artificial intelligence (AI) is being applied to smart energy systems to process massive and complex data in this sector and make smart and timely decisions. However, the lack of explainability and governability of AI is a major concern for stakeholders hindering a fast uptake of AI in the energy sector. This paper provides a review of AI explainability and governance in smart energy systems. We collect 3,568 relevant papers from the Scopus database, automatically discover 15 parameters or themes for AI governance in energy and elaborate the research landscape by reviewing over 150 papers and providing temporal progressions of the research. The methodology for discovering parameters or themes is based on “deep journalism,” our data-driven deep learning-based big data analytics approach to automatically discover and analyse cross-sectional multi-perspective information to enable better decision-making and develop better instruments for governance. The findings show that research on AI explainability in energy systems is segmented and narrowly focussed on a few AI traits and energy system problems. This paper deepens our knowledge of AI governance in energy and is expected to help governments, industry, academics, energy prosumers, and other stakeholders to understand the landscape of AI in the energy sector, leading to better design, operations, utilisation, and risk management of energy systems.

Efficient mRNA delivery using lipid nanoparticles modified with fusogenic coiled-coil peptides.

Gene delivery has great potential in modulating protein expression in specific cells to treat diseases. Such therapeutic gene delivery demands sufficient cellular internalization and endosomal escape. Of various nonviral nucleic acid delivery systems, lipid nanoparticles (LNPs) are the most advanced, but still, are very inefficient as the majority are unable to escape from endosomes/lysosomes. Here, we develop a highly efficient gene delivery system using fusogenic coiled-coil peptides. We modified LNPs, carrying EGFP-mRNA, and cells with complementary coiled-coil lipopeptides. Coiled-coil formation between these lipopeptides induced fast nucleic acid uptake and enhanced GFP expression. The cellular uptake of coiled-coil modified LNPs is likely driven by membrane fusion thereby omitting typical endocytosis pathways. This direct cytosolic delivery circumvents the problems commonly observed with the limited endosomal escape of mRNA. Therefore fusogenic coiled-coil peptide modification of existing LNP formulations to enhance nucleic acid delivery efficiency could be beneficial for several gene therapy applications.

Remarkable iodine uptake by aniline-based macrocyclic arenes through a reverse dissolution mechanism

Following a reverse dissolution mechanism, aniline-based macrocyclic arenes show significant iodine uptake capacities, fast uptake kinetics and good recyclability.

Implications of changes in physical state of drugs in poly(lactide-co-glycolide) matrices upon exposure to moisture and release medium

The objective of this study was to investigate the influence of the drug physical state (dissolved or dispersed) in poly(lactide-co-glycolide) (PLGA) on drug release and potential changes in physical state upon contact with moisture or release medium. PLGA matrices containing risperidone, ibuprofen or dexamethasone were prepared as films by solvent casting or as implants by hot melt extrusion. The physical state of the drugs in the polymer was examined by DSC and polarized light microscopy and the in-vitro drug release was compared for different drug physical states.Incubation of drug-PLGA matrices at 40 °C/75% RH (relative humidity) resulted in a decrease in microclimate pH in the PLGA matrices upon moisture uptake, dissolving initially dispersed risperidone because of an increased drug solubility in the matrix. In contrast, initially dissolved ibuprofen precipitated in the matrix because of a decrease in drug solubility at lower pH values and a fast water uptake. Dexamethasone did not show any change of physical state under the same conditions; the drug is barely soluble in the dry matrix and its solubility is not pH dependent. Risperidone was released faster from PLGA matrices with dissolved versus dispersed drug, substantially reducing the lag time. The crystallization process of ibuprofen could be inhibited by the use of a higher molecular weight PLGA grade. The inhibition resulted in a faster release from solid solution than from the corresponding solid dispersion. However, ibuprofen, which was deliberately precipitated on the surface of a PLGA matrix by incubation at 40 °C/75% RH, was able to bridge the lag time and led to a linearization of a typical PLGA release profile.In conclusion, a change in the physical state of the drug in PLGA affects the drug release profile. A change can be induced by incubation at 40 °C/75% RH. Furthermore, moisture contact and storage conditions of PLGA drug delivery systems should be carefully considered during handling to avoid undesired drug release changes.

Synergistic effect of doxorubicin lauroyl hydrazone derivative delivered by α-tocopherol succinate micelles for the treatment of glioblastoma

We hypothesized that tocopherol succinate (TOS) and D-α-tocopherol polyethylene2000 succinate (TPGS2000) micelles could work as a drug delivery system while enhancing the anti-cancer efficacy of doxorubicin lauryl hydrazone derivative (DOXC12) for the treatment of glioblastoma. The DOXC12-TOS-TPGS2000 micelles were formulated with synthesized DOXC12 and TPGS2000. They showed a high drug loading of hydrophobic DOXC12 (29%), a size of <100 nm and a pH sensitive drug release behaviour. In vitro, fast uptake of DOXC12-TOS-TPGS2000 micelles by GL261 cells was observed. For cytotoxicity, DOXC12-TOS-TPGS2000 micelles were evaluated on two glioblastoma cell lines and showed synergism between DOXC12 and TOS-TPGS2000. The higher cytotoxicity of DOXC12-TOS-TPGS2000 micelles was mainly caused by necrosis. The DOXC12-TOS-TPGS2000 micelles seem to be a promising delivery system for enhancing the anticancer efficacy of doxorubicin in glioblastoma (GBM).

Advanced sustainable carbon material from babassu biomass and its adsorption performance

Activated carbon (AC) wasprepared from babassu mesocarp, an abundant biomass inBrazil. Thermal pretreatments, including hydrothermal carbonization and pyrolysis at different temperatures were applied along with potassium hydroxide activation, in synthesizing ACs with varying structure, electronic and surface properties. A thorough characterization of the ACs revealed their low structural order and high specific surface area, containing micropores and mesopores. Furthermore, negatively charged surface oxygen functional groups make them potential candidates as adsorbents for cationic chemical species. A detailed study of adsorption of methylene blue cationic dye was carried out by varying time, initial concentration, pH and ionic strength of the dye solution, which showed that the chief driving force of this adsorption is the Coulombic interaction on the surface, followed by diffusion throughout the pores. These ACsshowed fast and efficient dye uptake – the best sample showedequilibrium adsorption capacity of 388 mg g−1for methylene blueand 220 mg g−1 for another cationic dye crystal violetduring 6 h –and thereby can be used as renewable and sustainable adsorbents.

Electrospun nanofiber mats as sorbents for polar emerging organic contaminants: Demonstrating tailorable material performance for uptake of neonicotinoid insecticides from water

The number and diversity of chemical contaminants in aquatic environments require versatile technologies for their removal. Here we fabricated various electrospun nanofiber mats (ENMs) and tested their ability to sorb six neonicotinoid insecticides, a model family of small, polar contaminants. ENM formulations were polyacrylonitrile (PAN) or carbon nanofibers (CNF; carbonized from PAN), with additives including carbon nanotubes (CNTs; with and without surface carboxyl groups), the cationic surfactant tetrabutyl ammonium bromide (TBAB), and/or phthalic acid (PTA; a CNF porogen). While sorption on pure PAN ENMs was low [equilibrium partition coefficients (KENM-W) from 0.9 to 1.2 log units (L/kg)], inclusion of CNTs and/or TBAB generally increased uptake in an additive fashion, with carboxylated CNT composites outperforming non-functionalized CNT analogs. CNF ENMs exhibited as much as a tenfold increase relative to PAN for neonicotinoid sorption, which increased with carbonization temperature. Ultimately, the optimal ENM (CNFs with carboxylated-CNTs, PTA, and carbonized at 800 °C) exhibited relatively fast uptake (equilibrium < 1 day without mixing) and surface-area-normalized capacities comparable to other carbonaceous sorbents (e.g., activated carbon). Collectively, this work demonstrates the versatility of electrospinning to produce novel sorbents specifically designed to target emerging chemical classes for applications including water treatment and passive sampling.

Synthesis and X-ray structure analysis of cytotoxic heptacoordinated Salan hafnium(IV) complexes stabilized with 2,6-dipicolinic acid

Four novel Salan Hf(IV) complexes stabilized by 2,6-dipicolinic acid (Dipic) were synthesized and characterized by 1H, 13C NMR and X-ray diffraction spectroscopy. These Hf(IV)bis-chelates could be obtained in good to excellent yields (88%–91%) and demonstrated rather good stability in aqueous media and on silica gel. [L2Hf(IV)Dipic4-H,Cl] containing steric bulk L2 were stable in about 10% H2O (H2O/THF (v/v)), however, [L1Hf(IV)Dipic4-H,Cl] with non-steric L1 could slowly dissociate and release nontoxic L1. [L1–2Hf(IV)Dipic4-Cl] showed excellent anti-tumoral activity in the range of cisplatin (Hela S3: IC50 = 3.5 ± 0.4 μM, Hep G2: IC50 = 11.2 ± 2.1 μM). In addition, the cellular uptake and apoptosis investigation of [L1Hf(IV)Dipic4-Cl] suggested a fast cellular uptake process against Hela S3 cells with an almost exclusive induced apoptosis cell death path.

Influencing Appropriate Statin Use in a Charity Care Primary Clinic.

According to the American College of Cardiology/American Heart Association (ACC/AHA) new cholesterol management guidelines in 2019, statin regimen was prescribed to only about 46.4% and 30% of diabetes (DM) patients and patients with atherosclerotic cardiovascular disease (ASCVD), respectively. Atherosclerotic cardiovascular disease accounts for most deaths and disabilities in North America. This study argues that a systematic approach to identifying targeted interventions to adhere to the statin regimen for ASCVD is sparse in previous studies. This study seeks to address the research gap. Besides, the study argues that the statin regimen could improve cholesterol management with the enablers of pharmacy, providers, electronic medical records (E.M.R.), and patients. It paves the way for future research on cardiovascular and statin regimens from different perspectives. Current study has adopted the Qualitative observation method. Accordingly, the study approached the charity care primary clinic serving a large population in the northeastern part of the United States, which constitutes the project's setting. The facility has 51 internal medicine residents. The facility has E.H.R., which is used by the clinical staff. Besides, providers use electronic medication prescribing (E-Scribe). Four PDSA cycles were run in six months. Here, the interventions were intensified during each subsequent cycle. The interventions were then incorporated into routine clinical practice. Based on the observation, the study found a 25% relative improvement by six months based on the baseline data of the appropriate intensity statin prescription for patients with ASCVD or DM by medical resident trainees in our single-center primary care clinic. A total of 77% of cardiovascular disease patients were found to be on an appropriate statin dose at baseline. On the other hand, the proportion of patients with DM who were on proper dose statin was 80.4%. According to the study's findings, PDSA could result in a faster uptake and support of the ACC/AHA guidelines. Evidence indicates that overmedication of persons at low risk and time constraints are some of the most significant impediments to the greater use of prescription medications. Proactive panel management can help improve statins' use by ensuring they are used appropriately.

Novel Hydrophobic Polyvinyl-Alcohol Formaldehyde Sponges: Synthesis, Characterization, Fast and Effective Organic Solvent Uptake from Contaminated Soil Samples

In the present research work, PVFTX-100, PVFSDS, and PVFT-80 sponges were prepared using polyvinyl-alcohol (PVA) with surfactants triton X-100/sodium dodecyl sulfate (SDS)/Tween 80, respectively, for the removal of organic solvents from polluted soil/water samples. All three obtained sponges were further made hydrophobic using dodecyltrimethoxysilane (DTMS). The prepared sponges were characterized using different spectroscopic techniques and SEM analysis. The peaks obtained near 1050 cm-1 and 790 cm-1 were attributed to Si-O-C and alkyl side chain C-H stretching vibration that confirmed the formation of desired sponges. The SEM images showed the random roughness with a number of protrusions on sponge surfaces, which further played an important role in the absorption and retention of organic solvents molecules. The Sears method was chosen to calculate the surface area and pore volume of all the synthesized sponge samples. Among all three prepared sponges, the PVFTX-100 sponge showed a high pore volume and large surface area, with a maximum percentage absorption capacity of 96%, 91%, 89.9%, 85.6%, and 80 for chlorobenzene, toluene, diesel, petrol, and hexane, respectively, after eightcycles. The organic solvent uptake using PVFTX-100, PVFSDS, and PVFT-80 sponges is quite a unique and simple technology, which could be employed at a large scale for contaminated soil/water systems.

Pairing Nanoparticles Geometry with TLR Agonists to Modulate Immune Responses for Vaccine Development.

Nanotechnology-based vaccine development necessitates understanding the crucial biophysical properties of nanostructures that alter immune responses. In this study, we demonstrate the synergistic effect of gold nanoparticles (AuNPs) shapes with toll-like receptor (TLR) agonists in immune modulation activity. Our results showed that CpG- and imidazoquinoline-conjugated rod-shaped AuNPs display relatively fast uptake by bone marrow-derived macrophage cells but exhibit poor immunogenic responses compared to their spherical and star-shaped AuNP counterparts. Surprisingly, star-shaped AuNPs exhibited intense pro-inflammatory cytokine secretion. Further mechanistic studies showed that star-shaped AuNPs were abundantly localized in the late endosome and lysosomal regions, whereas rod-shaped AuNPs were majorly sequestered in the mitochondrial region. These findings reveal that the shape of the nanostructures plays a pivotal role in driving the adjuvant molecules toward their receptors and altering immune responses.

Linear hydrogen bonded aggregates of carboxylic acids in crystalline channels of syndiotactic polystyrene

Sorption of long aliphatic carboxylic acids (lauric with 12 C atoms and stearic with 18 C atoms) and of an aliphatic dicarboxylic acid (adipic), by amorphous and nanoporous-crystalline δ-form and ε-form films of syndiotactic polystyrene (sPS), is reported. Fourier Transform Infrared (FTIR), Polarized FTIR and Wide Angle X-ray diffraction (WAXD) patterns show that the empty crystalline channels of the ε form are able to host long carboxylic acids as well as dicarboxylic acids. These acids are instead absorbed much more slowly and only from the amorphous phase for δ form sPS films, which exhibit crystalline cavities rather than crystalline channels. This selective and fast uptake of carboxylic acids in the crystalline channels of the sPS ε form is due the formation of hydrogen bonded linear dimers and linear polymers, for monocarboxylic and dicarboxylic acid guests, respectively.

Templating synthesis of oxime/amidoxime functionalized hollow nanospheres by air bubbles generated from “Ouzo-Like” effect for fast and massive uranium uptake

Simple and green synthesis of oxime or amidoxime functionalized hollow sorbents are critical for meeting the demands of highly efficient uranium extraction. To address this, a facile methodology using air bubbles generated from the “Ouzo-Like” effect as templates to synthesize oxime/amidoxime functionalized hollow PDA nanospheres (H-PDA-SO and H-PDA-AO) with fast and massive uranium extraction performances was reported. When 50 mL of Tris solution (0.6 mg mL−1) was mixed with n-propanol (6.25 mL) for 2.0 min, nanobubbles with the mean size of 56.7 nm spilled out, and uniformly sized H-PDA-SO nanospheres with oxime groups (about 250 nm) and H-PDA-AO nanospheres with amidoxime groups (about 150 nm) were simply obtained via self-assembled polydopamine and post-modification around the air/water interface. Owing to the accessible affinity sites and hollow structure, H-PDA-SO and H-PDA-AO displayed high maximum adsorption capacities (103.09 mg g−1 and 331.62 mg g−1 at 298 K) and fast adsorption rate (below 60 min) with high removal efficiency. Under the influence of coexisting ions, H-PDA-SO and H-PDA-AO showed not only a high uranium adsorption capacity but also a more predominant capacity than all the competing ions. Moreover, H-PDA-SO and H-PDA-AO exhibited high stability as well as excellent recyclability toward uranium capture after five regeneration cycles. Surface coordination of oxime/amidoxime sites with uranium was the main binding mechanism, and negative charged O-containing function groups enhance this affinity interactions.

One-pot synthesis of Al-containing mesoporous silicas in a mildly acidic condition for efficient tetracycline adsorption

Tetracycline (TC), one of the widely used antibiotics in wastewater, has caused serious interferences in human health and ecological balance. Herein, a series of Al-containing mesoporous silicas (Al–SiO2) were direct synthesized from mildly acidic solutions in which the acidity was self-generated by the AlCl3 precursor. Structure characterizations disclose that Al–SiO2 has both of long-range well-ordered and short-range ordered mesopores, large surface area (723–876 cm2 g−1), high pore volume (0.83–1.06 cm3 g−1), and a small number of Al species (0.44–1.10 wt %) in it. In batch tests, all Al–SiO2 materials present fast uptake and high removal efficiency (RE) towards high concentrated TC (C0 = 80 mg L−1, RE = 60–83%). Among them, the sample synthesized with rAl/Si = 1.0 displays the largest TC adsorption capacity (74.6 mg g−1), which is much higher than conventional SBA-15 (13.2 mg g−1), porous Al2O3 (27.8 mg g−1) and industrial SiO2 (3.4 mg g−1). Meanwhile, the Al–SiO2 possesses favorable removal efficiency in neutral pH range (pH = 5.0–7.0, RE > 77%), quite good selectivity to tetracycline and quinolone antibiotics, excellent cycling stability in the removal of TC (RE = 74% after six cycles). This study provides a simple and facile method for the synthesis of heteroatom-containing mesoporous adsorbents for the removal of antibiotics in wastewater.

A two-sorbent system for fast uptake of arsenate from water: Batch and column studies

There is a critical need to use decentralized and/or point-of-use systems to address some challenging water quality issues in society. Sorption-based approaches are uniquely suitable for such applications because of their simplicity in operation; however, the sorbents must possess fast contaminant uptake kinetics to overcome short hydraulic contact times often encountered in small systems. Here we designed a two-sorbent system consisting of Fe2O3-coated mesoporous carbon (FeMC) and nano-Fe2O3-coated activated carbon (FeAC) and demonstrated its ability to remove arsenate with a < 1 min empty bed contact time (EBCT) by a capture-and-storage process. Batch experiments showed rapid capture of arsenate by FeMC, likely occurred on the rod-like structures protruding to the liquid film. The captured arsenate could subsequently be relocated to FeAC for storage, which had a higher apparent sorption capacity. Column studies, operated with a 10 h running time followed by a 14 h pump-off time, showed that with a 102 μg-As/L influent concentration and at 0.85 min EBCT, the column treated 20,022 bed volumes until the 10 μg-As/L breakthrough, corresponding to a sorption density of 2.36 mg-As/g. This capture-and-storage technique resulted in a rapid and high-capacity arsenate removal through a combined effect of facile access to sorption sites on one sorbent and dynamic equilibrium in the two-sorbent system possessing a large total sorption capacity.