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1.
Anal Chem ; 92(8): 5772-5779, 2020 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-32212603

RESUMO

Reactivity based fluorescent probes have been widely investigated as a powerful and noninvasive tool for disease diagnosis in recent years. ß-Galactosidase (ß-gal), one of the typical lysosomal glycosidases, is reported to be a vital biomarker overexpressed in primary ovarian cancer cells. Fluorescent probes with excellent performance for endogenous ß-gal detection offer a unique option for visualization and diagnosis of primary ovarian cancer cells. Herein, a near-infrared fluorescent probe Lyso-Gal with lysosome-targeting ability was developed for lysosomal ß-gal detection and imaging in ovarian cancer cells (SKOV-3 cells). Lyso-Gal exhibits weak fluorescence in aqueous solution but emits bright NIR fluorescence at 725 nm after incubation with ß-gal. Highly selective imaging of ovarian cancer cells has been achieved upon incubation with Lyso-Gal for only 1 min. The detection time is extremely short. In comparison with a similar hemicyanine probe, Hx-Gal, without lysosome-targeting ability, Lyso-Gal realizes endogenous ß-gal visualization in lysosomes and shows brighter fluorescence than Hx-Gal in SKOV-3 cells. This work demonstrates the potential of Lyso-Gal for detection of primary ovarian cancer cells by using ß-gal as the biomarker.

2.
Kidney Int ; 97(4): 765-777, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32061436

RESUMO

Renal accumulation and exposure of cadmium originating from pollution in agricultural land and the prevalence of cigarette smoking remains an unneglectable human health concern. Whereas cadmium exposure has been correlated with increased incidence of a variety of kidney diseases, little is known pertaining to its effect on renal drug disposition and response in patients. Here, we report that cadmium exposure significantly increased the activity of organic cation transporter 2 (OCT2), a critical renal drug transporter recommended in United States Federal Drug Administration guidance for assessment during drug development. Cadmium enhanced OCT2 trafficking to the cell membrane both in vitro and in vivo. Mechanistically cadmium-mediated OCT2 translocation was found to involve protein-protein interaction between serine/threonine-protein kinase AKT2, calcium/calmodulin and the AKT substrate AS160 in in vitro cellular studies. The formed protein complex could selectively facilitate phosphorylation of AKT2 at T309, which induced translocation of OCT2 to the plasma membrane. Moreover, cadmium exposure markedly exacerbated nephrotoxicity induced by cisplatin, an OCT2 substrate, by increasing its accumulation in the mouse kidney. Consistently, there was a significant correlation between plasma cadmium level and alteration of renal function in cervical cancer patients who underwent chemotherapy with cisplatin. Thus, our studies suggest that membrane transporter distribution induced by cadmium exposure is a previously unrecognized factor for the broad variation in renal drug disposition and response.

3.
Theriogenology ; 147: 25-33, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32086048

RESUMO

Genetic modification is a rapidly developing field in which numerous significant breakthroughs have been achieved. Over the last few decades, genetic modification has evolved from insertional transgenesis to gene targeting and editing and, more recently, to base and prime editing using CRISPR-derived systems. Currently, CRISPR-based genome editing systems are showing great potential for generating gene-edited offspring with defined genetic characteristics. Domestic small ruminants (sheep and goats) have shown great potential as large animal models for genome engineering. Ovine and caprine genomes have been engineered using CRISPR-based systems for numerous purposes. These include generating superior agricultural breeds, expression of therapeutic agents in mammary glands, and developing animal models to be used in the study of human genetic disorders and regenerative medicine. The creation of these models has been facilitated by the continuous emergence and development of genetic modification tools. In this review, we provide an overview on how CRISPR-based systems have been used in the generation of gene-edited small ruminants through the two main pathways (embryonic microinjection and somatic cell nuclear transfer) and highlight the ovine and caprine genes that have been targeted via knockout, knockin, HDR-mediated point mutation, and base editing approaches, as well as the aims of these specific manipulations.

4.
Mycopathologia ; 185(2): 299-306, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31939052

RESUMO

OBJECTIVES: We sought to determine the occurrence, risk factors, effect of antifungal prophylaxis, and outcomes of invasive fungal infections (IFIs) in patients with acute myeloid leukemia (AML). PATIENTS AND METHODS: We performed a retrospective analysis of all adult patients admitted to the University of Michigan Health System for AML over a 3-year period from 2010 to 2013. We determined comorbidities, hematopoietic cell transplant (HCT) status, antifungal prophylaxis, proven and probable IFI, and outcomes at 12 weeks after initiation of appropriate antifungal therapy. RESULTS: Of 333 patients in our cohort, 116 of whom had received a HCT, 98 (29%) developed an IFI. Of the 30 (9%) patients who had a proven or probable IFI, 18 had breakthrough infection while on micafungin (n = 5), voriconazole (n = 4), posaconazole (n = 5), or fluconazole (n = 4). Breakthrough IFIs were due to Aspergillus species (n = 11), other molds (n = 4), and Candida species (n = 3). Factors associated with breakthrough IFI were prolonged severe neutropenia (p = .05) and having received tacrolimus (p = .04). Antifungal therapy was successful in 7 of the 18 (39%) patients with breakthrough IFI and 8 of the 12 (67%) patients with non-breakthrough IFI, p = .13. Mortality at 12 weeks was 27%, 5 with breakthrough IFI and 3 with non-breakthrough IFI and was associated with prolonged severe neutropenia, p = .04. CONCLUSIONS: Patients with AML remain at risk for IFI despite the use of several different antifungal agents for prophylaxis. Mortality remains high in patients with AML who develop IFI.

5.
Mycoses ; 62(12): 1189-1193, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31581342

RESUMO

BACKGROUND: The diagnosis of invasive pulmonary aspergillosis (IPA) remains challenging. We evaluated the performance characteristics of a newly formatted Aspergillus lateral flow test, AspLFD, in bronchoalveolar lavage (BAL) fluid from patients with classic risk factors for IPA. METHODS: Prospectively banked BAL samples from 14 patients with proven or probable IPA defined by EORTC/MSG criteria and 28 BAL samples from age-matched high-risk patients without IPA were tested with AspLFD according to manufacturer's directions. Results were read by two independent observers, and test performance was calculated. RESULTS: Age, gender and underlying risk factors, except for neutropenia and haematological malignancy, were similar between IPA cases and controls. Seven patients (50%) in the IPA group received a mould-active agent within 5 days prior to bronchoscopy compared with only three patients (11%) in the control group, P = .004. Of 14 patients with proven/probable IPA, AspLFD was positive in 3 and negative in 9; two tests yielded invalid results. All 28 control patients had a negative AspLFD test. AspLFD showed low sensitivity (25%, 95% CI: 5.5% to 57.2%), but high specificity (100%. (95% CI: 87.7% to 100%). CONCLUSIONS: A positive AspLFD test in BAL fluid of patients with classic risk factors for IPA could be useful to support the diagnosis of proven/probable IPA because of its high specificity. However, as a stand-alone test for IPA, the use of AspLFD is limited by low sensitivity.

6.
Front Genet ; 10: 750, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31552084

RESUMO

Sheep and goats are valuable livestock species that have been raised for their production of meat, milk, fiber, and other by-products. Due to their suitable size, short gestation period, and abundant secretion of milk, sheep and goats have become important model animals in agricultural, pharmaceutical, and biomedical research. Genome engineering has been widely applied to sheep and goat research. Pronuclear injection and somatic cell nuclear transfer represent the two primary procedures for the generation of genetically modified sheep and goats. Further assisted tools have emerged to enhance the efficiency of genetic modification and to simplify the generation of genetically modified founders. These tools include sperm-mediated gene transfer, viral vectors, RNA interference, recombinases, transposons, and endonucleases. Of these tools, the four classes of site-specific endonucleases (meganucleases, ZFNs, TALENs, and CRISPRs) have attracted wide attention due to their DNA double-strand break-inducing role, which enable desired DNA modifications based on the stimulation of native cellular DNA repair mechanisms. Currently, CRISPR systems dominate the field of genome editing. Gene-edited sheep and goats, generated using these tools, provide valuable models for investigations on gene functions, improving animal breeding, producing pharmaceuticals in milk, improving animal disease resistance, recapitulating human diseases, and providing hosts for the growth of human organs. In addition, more promising derivative tools of CRISPR systems have emerged such as base editors which enable the induction of single-base alterations without any requirements for homology-directed repair or DNA donor. These precise editors are helpful for revealing desirable phenotypes and correcting genetic diseases controlled by single bases. This review highlights the advances of genome engineering in sheep and goats over the past four decades with particular emphasis on the application of CRISPR/Cas9 systems.

7.
Artigo em Inglês | MEDLINE | ID: mdl-31449353

RESUMO

Protected by the host cells, the hidden intracellular bacteria are typically difficult to kill by common antibiotics and cannot be visualized without complex cellular pretreatments. Herein, we successfully developed a bacteria-metabolizable dual-functional probe TPEPy-d-Ala, which is based on d-alanine and a photosensitizer with aggregation-induced emission for fluorescence turn-on imaging of intracellular bacteria in living host cells and photodynamic ablation in situ. Once metabolically incorporated into bacterial peptidoglycan, the intramolecular motions of TPEPy-d-Ala are inhibited, leading to an enhanced fluorescent signal, which allows the clear visualization of the intracellular bacteria. Moreover, TPEPy-d-Ala can effectively ablate the labeled intracellular bacteria in situ owing to covalent ligation to peptidoglycan, yielding a low intracellular minimum inhibitory concentration (MIC) of 20±0.5 µg mL-1 , much more efficient than that of a commonly used antibiotic, vancomycin.

8.
FEBS J ; 286(23): 4675-4692, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31276295

RESUMO

The ability to alter single bases without homology directed repair (HDR) of double-strand breaks provides a potential solution for editing livestock genomes for economic traits, which are often multigenic. Progress toward multiplex editing in large animals has been hampered by the costly inefficiencies of HDR via microinjection of in vitro manipulated embryos. Here, we designed sgRNAs to induce nonsense codons (C-to-T transitions) at four target sites in caprine FGF5, which is a crucial regulator of hair length in mammals. Initial transfections of the third generation Base Editor (BE3) plasmid and four different sgRNAs into caprine fibroblasts were ineffective in altering FGF5. In contrast, all five progenies produced from microinjected single-cell embryos had alleles with a targeted nonsense mutation. The effectiveness of BE3 to make single base changes varied considerably based on sgRNA design. In addition, the rate of mosaicism differed between animals, target sites, and tissue type. The phenotypic effects on hair fiber were characterized by hematoxylin and eosin, immunofluorescence staining, and western blotting. Differences in morphology were detectable, even though mosaicism was probably affecting the levels of FGF5 expression. PCR amplicon and whole-genome resequencing analyses for off-target changes caused by BE3 were low at a genome-wide scale. This study provided the first evidence of base editing in large mammals produced from microinjected single-cell embryos. Our results support further optimization of BEs for introgressing complex human disease alleles into large animal models, to evaluate potential genetic improvement of complex health and production traits in a single generation.

9.
Sensors (Basel) ; 19(11)2019 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-31181614

RESUMO

In this paper, we propose a novel multi-view image denoising algorithm based on convolutional neural network (MVCNN). Multi-view images are arranged into 3D focus image stacks (3DFIS) according to different disparities. The MVCNN is trained to process each 3DFIS and generate a denoised image stack that contains the recovered image information for regions of particular disparities. The denoised image stacks are then fused together to produce a denoised target view image using the estimated disparity map. Different from conventional multi-view denoising approaches that group similar patches first and then perform denoising on those patches, our CNN-based algorithm saves the effort of exhaustive patch searching and greatly reduces the computational time. In the proposed MVCNN, residual learning and batch normalization strategies are also used to enhance the denoising performance and accelerate the training process. Compared with the state-of-the-art single image and multi-view denoising algorithms, experiments show that the proposed CNN-based algorithm is a highly effective and efficient method in Gaussian denoising of multi-view images.

10.
Reprod Fertil Dev ; 2019 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-31079595

RESUMO

The clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 system is an efficient method for the production of gene-edited animals. We have successfully generated gene-modified goats and sheep via zygote injection of Cas9 mRNA and single-guide RNA (sgRNA) mixtures. However, the delivery system for microinjection largely refers to methods established for mice; optimised injection conditions are urgently required for the generation of large animals. Here, we designed a study to optimise the Cas9 mRNA and sgRNA delivery system for goats. By comparing four computational tools for sgRNA design and validating the targeting efficiency in goat fibroblasts, we suggest a protocol for the selection of desirable sgRNAs with higher targeting efficiency and negligible off-target mutations. We further evaluated the editing efficiency in goat zygotes injected with Cas9:sgRNA (sg8) and found that injection with 50ngµL-1 Cas9 mRNA and 25ngµL-1 sgRNA yielded an increased editing efficiency. Our results provide a reference protocol for the optimisation of the injection conditions for the efficient editing of large animal genomes via the zygote injection approach.

11.
Biochem Biophys Res Commun ; 512(4): 779-785, 2019 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-30928098

RESUMO

3-oxoacid CoA-transferase 1 (OXCT1) is a key enzyme in ketone body metabolism that is expressed in adipose and other tissues. The present study addressed the function of OXCT1 in adipose tissue from Tan sheep. The 1563 bp ovine OXCT1 coding sequence was cloned from ovine adipose tissue. The OXCT1 protein sequence was highly homologous to OXCT1 from other species. OXCT1 was highly expressed in kidney and at lower levels in small intestine, lung, spleen, heart, stomach, liver, tail adipose, and cartilage, but not in longissimus muscle. OXCT1 was expressed at higher levels in perirenal and tail adipose tissues than in subcutaneous adipose tissue. OXCT1 expression levels increased during the in vitro differentiation of adipocytes, but decreased dramatically at day 8. OXCT1 knockdown in ovine adipocytes promoted lipid accumulation, whereas overexpression did the converse. This study demonstrates that OXCT1 may play a role in adipogenesis and provides new insight on adipose deposition in sheep.

12.
Front Genet ; 10: 215, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30930940

RESUMO

Since its emergence, CRISPR/Cas9-mediated base editors (BEs) with cytosine deaminase activity have been used to precisely and efficiently introduce single-base mutations in genomes, including those of human cells, mice, and crop species. Most production traits in livestock are induced by point mutations, and genome editing using BEs without homology-directed repair of double-strand breaks can directly alter single nucleotides. The p.96R > C variant of Suppressor cytokine signaling 2 (SOCS2) has profound effects on body weight, body size, and milk production in sheep. In the present study, we successfully obtained lambs with defined point mutations resulting in a p.96R > C substitution in SOCS2 by the co-injection of BE3 mRNA and a single guide RNA (sgRNA) into sheep zygotes. The observed efficiency of the single nucleotide exchange in newborn animals was as high as 25%. Observations of body size and body weight in the edited group showed that gene modification contributes to enhanced growth traits in sheep. Moreover, targeted deep sequencing and unbiased family trio-based whole genome sequencing revealed undetectable off-target mutations in the edited animals. This study demonstrates the potential for the application of BE-mediated point mutations in large animals for the improvement of production traits in livestock species.

13.
Anal Biochem ; 577: 110-116, 2019 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-31034799

RESUMO

It is of great value to develop general, low-cost and even household methods for colorectal cancer detection. Here, a portable detection strategy based on a personal glucose meter (PGM) was designed for meeting this purpose. In this strategy, the anti-EpCAM coated magnet beads (MBs) were used as capture probes for enriching cancer cells and the aptamer modified and invertase loaded graphene oxides (GO) were used as report probes for producing glucose signal. This method is sensitive with detection limit as low as 560 cells, and demonstrates excellent detection specificity. Meanwhile, we succeeded in the specific detection of target cells in 20% human serum samples, indicating this method has great prospect in clinical diagnosis. Moreover, this method presents favourable universality for detecting different colorectal cancer cells by just using different recognition aptamers. Importantly, this method can be implemented for the target cell detection at room temperature without any expensive and large-scale instruments but a portable PGM. Therefore, this portable detection method possesses great potential in point-of-care detection of colorectal cancer cells.

14.
J Mech Behav Biomed Mater ; 89: 150-161, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30286374

RESUMO

OBJECTIVES: This study aimed to develop a simple and efficient numerical modeling approach for characterizing strain and total strain energy in bone scaffolds implanted in patient-specific anatomical sites. MATERIALS AND METHODS: A simplified homogenization technique was developed to substitute a detailed scaffold model with the same size and equivalent orthotropic material properties. The effectiveness of the proposed modeling approach was compared with two other common homogenization methods based on periodic boundary conditions and the Hills-energy theorem. Moreover, experimental digital image correlation (DIC) measurements of full-field surface strain were conducted to validate the numerical results. RESULTS: The newly proposed simplified homogenization approach allowed for fairly accurate prediction of strain and total strain energy in tissue scaffolds implanted in a large femur mid-shaft bone defect subjected to a simulated in-vivo loading condition. The maximum discrepancy between the total strain energy obtained from the simplified homogenization approach and the one obtained from detailed porous scaffolds was 8.8%. Moreover, the proposed modeling technique could significantly reduce the computational cost (by about 300 times) required for simulating an in-vivo bone scaffolding scenario as the required degrees of freedom (DoF) was reduced from about 26 million for a detailed porous scaffold to only 90,000 for the homogenized solid counterpart in the analysis. CONCLUSIONS: The simplified homogenization approach has been validated by correlation with the experimental DIC measurements. It is fairly efficient and comparable with some other common homogenization techniques in terms of accuracy. The proposed method is implicating to different clinical applications, such as the optimal selection of patient-specific fixation plates and screw system.


Assuntos
Osso e Ossos/citologia , Análise de Elementos Finitos , Estresse Mecânico , Tecidos Suporte , Fenômenos Biomecânicos , Fêmur/citologia , Modelos Biológicos , Porosidade
15.
Front Genet ; 9: 449, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30356875

RESUMO

Unintended off-target mutations induced by CRISPR/Cas9 nucleases may result in unwanted consequences, which will impede the efficient applicability of this technology for genetic improvement. We have recently edited the goat genome through CRISPR/Cas9 by targeting MSTN and FGF5, which increased muscle fiber diameter and hair fiber length, respectively. Using family trio-based sequencing that allow better discrimination of variant origins, we herein generated offspring from edited goats, and sequenced the members of four family trios (gene-edited goats and their offspring) to an average of ∼36.8× coverage. This data was to systematically examined for mutation profiles using a stringent pipeline that comprehensively analyzed the sequence data for de novo single nucleotide variants, indels, and structural variants from the genome. Our results revealed that the incidence of de novo mutations in the offspring was equivalent to normal populations. We further conducted RNA sequencing using muscle and skin tissues from the offspring and control animals, the differentially expressed genes (DEGs) were related to muscle fiber development in muscles, skin development, and immune responses in skin tissues. Furthermore, in contrast to recently reports of Cas9 triggered p53 expression alterations in cultured cells, we provide primary evidence to show that Cas9-mediated genetic modification does not induce apparent p53 expression changes in animal tissues. This work provides adequate molecular evidence to support the reliability of conducting Cas9-mediated genome editing in large animal models for biomedicine and agriculture.

16.
Chem Commun (Camb) ; 54(72): 10092-10095, 2018 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-30124227

RESUMO

A conjugated polymer of poly(fluorene-co-benzothiadiazole) (PFBT) was modified by a soft segment of poly(dimethylsiloxane) (PDMS) to yield a copolymer via dynamic imine bonds. The copolymer was casted as a free-standing film, which was intrinsically flexible, stretchable, and showed tunable shape memory, healable and degradable effects.

17.
Materials (Basel) ; 11(7)2018 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-29954103

RESUMO

The weak stiffness and strength of materials with negative Poisson's ratio limits their application. In this paper, three types of novel lattices with negative Poisson's ratio are proposed to improve not only stiffness and strength but also energy absorption capacity by embedding different ribs into a classic re-entrant structure. Unit cell analyses show these novel lattices have significantly increased Young's modulus along the loading direction, and Type C can maintain sufficient negative Poisson's ratio performance compared with the base lattice. In addition, the novel lattices exhibit higher yield stress, plateau stress and densification strain extracted from quasi-static compressive simulation. The lattices are prototyped by laser-based additive manufacturing and tested in quasi-static experiments, which show the experimental data match the numerical results within an error of margin. The work signifies the prospect of lattices with negative Poisson's ratio in enhancing engineering-applicable structures, and indicates the potential of structural topology optimization in more sophisticated designs.

18.
Biosens Bioelectron ; 117: 260-266, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-29909197

RESUMO

The accurate therapeutic evaluation for chronic myeloid leukemia (CML) drug is of great importance to minimize side effects and enhance efficacy. Herein, a facile and precise surface-enhanced scattering (SERS) approach based on coupled plasmonic field has been introduced to evaluate the therapeutic outcomes of antileukemia drug through ultrasensitive assay of caspase-3 activity in apoptotic cells. Caspase-3 as an apoptosis indicator could specifically cleave the N-terminus of biotinylated DEVD-peptide (biotin-Gly-Asp-Gly-Asp-Glu-Val-Asp-Gly-Cys) immobilized on the Au nanoparticle-decorated TiO2 nanotube arrays (TiO2/Au NTAs) substrate. After the enzyme cleavage with caspase-3, Raman-labelled Au nanostar (AuNS) probes captured the residual DEVD-peptides via the recognition between streptavidin and biotin, thus resulting in an enhanced Raman response on the SERS platform. The variation of Raman intensity revealed caspase-3 activity that reflected the chemotherapeutic effect. On this platform, AuNS nanoprobes offered a large number of binding sites and intrinsic "hot spots" for Raman reporters, while TiO2/Au NTAs rendered a homogenously coupled electromagnetic field between the adjacent repeated units over the large area. In particular, a spatially expanding plasmonic field formed by coupling AuNSs with TiO2/Au NTAs would further heighten Raman enhancement. Taking these advantages, the strong and uniform Raman signals were achieved. Furthermore, the practicability investigation witnessed that the proposed SERS strategy was available to evaluate the therapeutic effect of dasatinib on CML K562 cells. The developed method possesses fascinating advantages of cost-effectiveness, excellent reproducibility and high sensitivity, which endows it with promising potential in apoptosis monitoring and anticancer drug development.


Assuntos
Avaliação de Medicamentos/métodos , Ouro/química , Nanotubos/química , Análise Espectral Raman/instrumentação , Avaliação de Medicamentos/instrumentação , Humanos , Células K562 , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Reprodutibilidade dos Testes , Titânio/química
19.
Bioinspir Biomim ; 13(5): 051001, 2018 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-29923834

RESUMO

Being one of the commonest deformation modes for soft matter, shell buckling is the primary reason for the growth and nastic movement of many plants, as well as the formation of complex natural morphology. On-demand regulation of buckling-induced deformation associated with wrinkling, ruffling, folding, creasing and delaminating has profound implications for diverse scopes, which can be seen in its broad applications in microfabrication, 4D printing, actuator and drug delivery. This paper reviews the recent remarkable developments in the shell buckling of soft matter to explain the most representative natural morphogenesis from the perspectives of theoretical analysis in continuum mechanics, finite element analysis, and experimental validations. Imitation of buckling-induced shape transformation and its applications are also discussed for the innovations of sophisticated materials and devices in future.


Assuntos
Materiais Biomiméticos/química , Simulação por Computador , Sistemas de Liberação de Medicamentos/métodos , Análise de Elementos Finitos
20.
Environ Sci Pollut Res Int ; 25(20): 20116-20124, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29748800

RESUMO

Two ferromanganese oxide-biochar composites (FMBC1 and FMBC2) were prepared by an impregnation method to promote the adsorption of As on red soil. Maximum adsorption capacities (Qm) of 0.687 and 0.712 mg g-1 were observed for FMBC1 and FMBC2, respectively, corresponding to increases of 104 and 111% relative to the control treatment (Qm = 0.337 mg g-1). Treatment with FMBC1 increased the pH of red soil, whereas a reverse trend was observed for FMBC2. A variety of analytical techniques were used to explain the differences between FMBC1 and FMBC2, revealing that the oxidation of As(III) to As(V) by Mn and Fe oxides was aided by interactions with the oxygen-containing functional groups of the ferromanganese oxide-biochar composites. Thus, red soil supplemented with the ferromanganese oxide-biochar composites mainly adsorbed As by chemisorption, thereby projecting ferromanganese oxide-biochar composites as potential absorbents for effectively remediating As-polluted red soil.


Assuntos
Arsênico/análise , Carvão Vegetal/química , Poluição Ambiental/prevenção & controle , Recuperação e Remediação Ambiental/métodos , Ferro/química , Manganês/química , Óxidos/química , Poluentes do Solo/análise , Adsorção
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