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1.
Int J Environ Health Res ; 31(1): 85-101, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31210533

RESUMO

Diclofenac is a commercial non-steroidal anti-inflammatory drug commonly present as a pollutant in naturally occurring water sources and wastewaters. In this work, the adsorption of diclofenac onto chitosan-coated magnetic nanosystems is proposed as a possible tool for remediation. Experimental and theoretical studies have been carried out to reveal the mechanisms associated with diclofenac interactions among all the components of the nanosystem. Mechanisms are presented, analyzed and discussed. A toxicological study in mice was carried out to evaluate the parameters associated with neurotoxicity of the nanodevice. The elucidation of the mechanisms implied in the adsorption process of diclofenac onto magnetic chitosan nanocomposites suggests that diclofenac remediation from water is possible by adsorption onto chitosan. The strategy innovates the commonly used methodologies for diclofenac remediation from pharmaceutical wastes. This magnetic nanotechnology would not induce damage on the nervous system in a murine model, in case of traces remaining in water sources.


Assuntos
Diclofenaco/análise , Recuperação e Remediação Ambiental/instrumentação , Nanotecnologia/instrumentação , Poluentes Químicos da Água/química , Poluição Química da Água/prevenção & controle , Adsorção , Anti-Inflamatórios não Esteroides/análise , Fenômenos Magnéticos , Águas Residuárias/análise
2.
J Mater Sci Mater Med ; 31(2): 22, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32002683

RESUMO

The role Beta-cyclodextrin (ßCD) on improving biocompatibility on healthy cellular and animal models was studied upon a formulation obtained from the development of a simple coating procedure. The obtained nanosystems were thoroughly characterized by FTIR, TGA, atomic absorption spectroscopy, dynamic light scattering and zeta potential, TEM/HR-TEM and magnetic properties. ßCD might interact with the magnetic core through hosting OA. It is feasible that the nanocomposite is formed by nanoparticles of MG@OA dispersed in a ßCD matrix. The evaluation of ßCD role on biocompatibility was performed on two healthy models. To this end, in vivo studies were carried out on Caenorhabditis elegans. Locomotion and progeny were evaluated after exposure animals to MG, MG@OA, and MG@OA-ßCD (10 to 500 µg/mL). The influence of ßCD on cytotoxicity was explored in vitro on healthy rat aortic endothelial cells, avoiding alteration in the results derived from the use of transformed cell lines. Biological studies demonstrated that ßCD attaching improves MG biocompatibility.


Assuntos
Magnetismo , Teste de Materiais , Nanocompostos/química , Nanocompostos/toxicidade , beta-Ciclodextrinas/química , Animais , Caenorhabditis elegans , Sobrevivência Celular , Relação Dose-Resposta a Droga , Células Endoteliais/efeitos dos fármacos , Endotélio Vascular/citologia , Estrutura Molecular , Nanocompostos/administração & dosagem , Ratos , Ratos Wistar , Propriedades de Superfície
3.
Toxicol Appl Pharmacol ; 358: 23-34, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30205093

RESUMO

Doxorubicin (DOXO) is a chemotherapeutic agent widely used for the treatment of solid tumors and hematologic malignancies in both adults and children. However, DOXO causes short- and long-term cardiotoxicity and others undesirable side effects, such as nephrotoxicity and neurotoxicity. Magnetic nanoparticles (MNPs) allow the delivery of drugs specifically to target place, employing an external magnet. Moreover, they may act as contrast agents in MRI providing information on the diagnostic of diverse pathologies. In this way, two functions may be combined in a unique nanosystem known as theranostic. Also, the MNPs can be modified with folic acid (MNPs@FA) to increase the uptake by cancer cells that overexpress the FA receptors. In previous works, our collaborators obtained and characterized MNPs, MNPs@FA, and MNPs@FA@DOXO. It is essential to study the biosafety of nanotheranostic, and there is no published study of Fe3O4 nanoparticles developmental toxicity. Because of that, this work aimed to study the in vivo toxicity and biocompatibility of DOXO, MNPs@FA, and MNPs@FA@DOXO using zebrafish embryo and larvae as an animal model. Viability, developmental toxicity, changes in spontaneous movement (neurotoxicity), changes in cardiac rhythm (cardiotoxicity), and efficiency of DOXO-uptake were studied. While the 48-h treatment with 50 µg/mL of DOXO resulted in a 30% larvae death and the development of significant morphological abnormalities, the treatment with MNPs@FA@DOXO and MNPs@FA did not reduce the viability and did not cause developmental abnormalities. Besides, the MNPs@FA@DOXO reduced the cardiotoxicity and promoted a more rapid and significant uptake of DOXO by zebrafish larvae.


Assuntos
Antibióticos Antineoplásicos/toxicidade , Doxorrubicina/toxicidade , Sistemas de Liberação de Medicamentos/métodos , Ácido Fólico/toxicidade , Nanopartículas de Magnetita/toxicidade , Nanomedicina Teranóstica/métodos , Animais , Antibióticos Antineoplásicos/administração & dosagem , Relação Dose-Resposta a Droga , Doxorrubicina/administração & dosagem , Doxorrubicina/metabolismo , Ácido Fólico/administração & dosagem , Ácido Fólico/metabolismo , Larva/efeitos dos fármacos , Larva/metabolismo , Nanopartículas de Magnetita/administração & dosagem , Peixe-Zebra
4.
Bioprocess Biosyst Eng ; 41(2): 171-184, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29064034

RESUMO

Magnetic biocatalysts offer enormous advantages over traditional ones. Their ability to be isolated by means of a magnet, in combination with their extensive reuse possibilities, makes them highly attractive and competitive from the commercial point of view. In this work, magnetic biocatalysts were prepared by immobilization of Candida antarctica Lipase B (E.C. 3.1.1.3, CALB) on magnetite-lysine nanoparticles. Two methodologies were explored tending to find the optimal biocatalyst in terms of its practical implementation: I-physical adsorption of CALB followed by cross-linking, and II-covalent coupling of the lipase on the nanoparticles surface. Both procedures involved the use of glutaraldehyde (GLUT) as cross-linker or coupling agent, respectively. A range of GLUT concentrations was evaluated in method I and the optimum one, in terms of efficiency and operational stability, was chosen to induce the covalent linkage CALB-support in method II. The chosen test reaction was solvent-free ethyl oleate synthesis. Method I produced operationally unstable catalysts that deactivated totally in four to six cycles. On the other hand, covalently attached CALB (method II) preserved 60% of its initial activity after eight cycles and also retained 90% of its initial activity along 6 weeks in storage. CALB immobilization by covalent linkage using controlled GLUT concentration appears as the optimum methodology to asses efficient and stable biocatalysts. The materials prepared within this work may be competitive with commercially available biocatalysts.


Assuntos
Candida/enzimologia , Enzimas Imobilizadas/química , Proteínas Fúngicas/química , Lipase/química , Lisina/química , Nanopartículas de Magnetita/química , Catálise , Propriedades de Superfície
5.
J Nanosci Nanotechnol ; 14(5): 3343-7, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24734550

RESUMO

New magnetic devices consisting of magnetite functionalized with oleic acid and chitosan have been synthesized and employed to the loading of Diclofenac as potential tool for treatment of targeted inflammatory diseases. Magnetic loaded and un-loaded nanoparticles have been thoroughly characterized by infrared spectroscopy, transmission electron microscopy, determination of hydrodynamic diameter by Dynamic light scattering and zeta potential measurements at different pH conditions. A study of the release of Diclofenac has been performed in vitro and available mathematical models have been used to determine the release kinetic. Both properties and release data reveal that this nanomagnetic platform would be suitable for in vivo assays.


Assuntos
Anti-Inflamatórios não Esteroides/administração & dosagem , Quitosana/química , Diclofenaco/administração & dosagem , Magnetismo , Nanopartículas , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/farmacocinética , Diclofenaco/química , Diclofenaco/farmacocinética , Sistemas de Liberação de Medicamentos , Microscopia Eletrônica de Transmissão , Espectrofotometria Infravermelho
6.
Bioprocess Biosyst Eng ; 37(3): 585-91, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23860559

RESUMO

Candida antarctica Lipase B was successfully immobilized on magnetite (Fe3O4) nanoparticles functionalized with chitosan and glutaraldehyde. The obtained magnetic catalyst was characterized and its performance was evaluated in solvent-free synthesis of ethyl oleate at room temperature. The performance of this biocatalyst was compared with the commercial Novozym 435, as a tool to estimate the efficiency of immobilization. It was found that using 33 mg of the biocatalyst it was possible to reach almost the same activity that was obtained using 12 mg of Novozym 435. Furthermore, this new biocatalyst presents the advantages of not being degraded by short alcohols, being easily recovered from the reaction media by magnetic decantation, and low fabrication cost. The possibility of reutilization was also studied, keeping a significant activity up to eight cycles. A special sampling protocol was also developed for the multiphasic reaction system, to assure accurate results. This novel biocatalyst is an interesting alternative for potential industrial applications, considering the above-mentioned advantages.


Assuntos
Biocatálise , Candida/enzimologia , Magnetismo , Ácidos Oleicos/biossíntese , Microscopia Eletrônica de Transmissão , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier
7.
J Biomater Appl ; 38(9): 1000-1009, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38456269

RESUMO

Morin is an antioxidant and anticancer flavonoid, extracted from natural sources, that may exert beneficial effects for several pathologies. Despite this, the administration of morin represents a challenge due to its low aqueous solubility. Mesoporous silica materials have emerged as biocompatible tools for drug delivery, as their pore size can be modulated for maximum surface area to volume ratio. In this contribution, we evaluate the ability of iron-modified mesoporous materials, for morin loading and controlled delivery. The SBA-15 and MCM-41 sieves were synthesized and modified with iron (metal content 4.02 and 6.27 % wt, respectivily). Characterization by transmission electron microscopy, XRD and UV-Vis revealed adequate pore size and agglomerates of very small metallic nanospecies (nanoclusters), without larger iron oxide nanoparticles. FT-IR spectra confirmed the presence of silanol groups in the solid hosts, which can interact with different groups present in morin molecules. SBA-15 materials were more efficient in terms of morin loading capacity (LC) due to their larger pore diameter. LC was more than 35% for SBA-15 materials when adsorptions studies were carried out with 9 mg of drug. Antioxidant activity were assayed by using DPPH test. Free iron materials presented a significate improvement as antioxidants after morin incorporation, reaching a scavenging activity of almost a 90%. On the other hand, in iron modified mesoporous materials, the presence of morin did not affect the scavenging activity. The results could be related with the formation of a complex between the flavonoid and the iron. Finally, biosafety studies using normal epithelial cells revealed that neither the loaded nor the unloaded materials exerted toxicity, even at doses of 1 mg/ml. These findings expand knowledge about mesoporous materials as suitable carriers of flavonoids with the aim of improving therapies for a wide range of pathologies.


Assuntos
Flavonas , Flavonoides , Neoplasias , Humanos , Espectroscopia de Infravermelho com Transformada de Fourier , Flavonoides/química , Dióxido de Silício/química , Antioxidantes/química , Ferro , Porosidade
8.
IEEE Trans Nanobioscience ; 22(1): 11-18, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-34928800

RESUMO

Magnetic iron oxide nanoparticles (MNPs) coated with citric acid (MG@CA) are proposed as raw materials for the treatment of bone diseases. Citric acid (CA) was selected as coating due to its role in the stabilization of apatite nanocrystals and as a signaling agent for osteoblast activation. Raloxifene (Ral), curcumine (Cur) and methylene blue (MB) were employed as model drugs as therapeutic agents for bone diseases. Characterization of raw and drug loaded nanosystems was conducted in order to elucidate the mechanisms governing interactions between therapeutics and the magnetic platform. Biocompatibility studies were performed on red blood cells (RBCs) from peripheral human blood. Cytotoxicity was evaluated on endothelial cells (ECs); and viability was studied for bone cells exposed at concentrations of 1, 10 and 100 [Formula: see text]/mL of the magnetic nano-platform. MG@CA exhibited proper physicochemical properties for the applications intended within this work. It presented satisfactory biocompatibility on peripheral red blood cells. Only doses of 100 [Formula: see text]/mL induced a decrease in metabolic activity of ECs and MC3T3-E1 cells. Drug adsorption efficiency was estimated as 62.0, 15.0 and 54.0 % for Ral, Cur and MB and drug loading capability of 12.0, 20.0 and 13.6%, respectively.


Assuntos
Doenças Ósseas , Nanopartículas de Magnetita , Humanos , Células Endoteliais/metabolismo , Sistemas de Liberação de Medicamentos , Cloridrato de Raloxifeno/metabolismo , Doenças Ósseas/metabolismo , Ácido Cítrico/química , Ácido Cítrico/metabolismo , Fenômenos Magnéticos , Nanopartículas de Magnetita/química
9.
Pharmaceutics ; 15(2)2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36839809

RESUMO

Magnetic nanosystems represent promising alternatives to the traditional diagnostic and treatment procedures available for different pathologies. In this work, a series of biological tests are proposed, aiming to validate a magnetic nanoplatform for Kaposi's sarcoma treatment. The selected nanosystems were polyethylene glycol-coated iron oxide nanoparticles (MAG.PEG), which were prepared by the hydrothermal method. Physicochemical characterization was performed to verify their suitable physicochemical properties to be administered in vivo. Exhaustive biological assays were conducted, aiming to validate this platform in a specific biomedical field related to viral oncogenesis diseases. As a first step, the MAG.PEG cytotoxicity was evaluated in a cellular model of Kaposi's sarcoma. By phase contrast microscopy, it was found that cell morphology remained unchanged regardless of the nanoparticles' concentration (1-150 µg mL-1). The results, arising from the crystal violet technique, revealed that the proliferation was also unaffected. In addition, cell viability analysis by MTS and neutral red assays revealed a significant increase in metabolic and lysosomal activity at high concentrations of MAG.PEG (100-150 µg mL-1). Moreover, an increase in ROS levels was observed at the highest concentration of MAG.PEG. Second, the iron quantification assays performed by Prussian blue staining showed that MAG.PEG cellular accumulation is dose dependent. Furthermore, the presence of vesicles containing MAG.PEG inside the cells was confirmed by TEM. Finally, the MAG.PEG steering was achieved using a static magnetic field generated by a moderate power magnet. In conclusion, MAG.PEG at a moderate concentration would be a suitable drug carrier for Kaposi's sarcoma treatment, avoiding adverse effects on normal tissues. The data included in this contribution appear as the first stage in proposing this platform as a suitable future theranostic to improve Kaposi's sarcoma therapy.

10.
ChemMedChem ; 17(5): e202100685, 2022 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-34978134

RESUMO

Hearing loss (HL) is a sensory disability that affects 5 % of the world's population. HL predominantly involves damage and death to the cochlear cells. Currently, there is no cure or specific medications for HL. Furthermore, the arrival of therapeutic molecules to the inner ear represents a challenge due to the limited blood supply to the sensory cells and the poor penetration of the blood-cochlear barrier. Superparamagnetic iron oxide nanoparticles (SPIONs) perfectly coordinate with the requirements for controlled drug delivery along with magnetic resonance imaging (MRI) diagnostic and monitoring capabilities. Besides, they are suitable tools to be applied to HL, expecting to be more effective and non-invasive. So far, the published literature only refers to some preclinical studies of SPIONs for HL management. This contribution aims to provide an integrated view of the best options and strategies that can be considered for future research punctually in the field of magnetic nanotechnology applied to HL.


Assuntos
Perda Auditiva , Nanomedicina Teranóstica , Sistemas de Liberação de Medicamentos , Perda Auditiva/diagnóstico , Perda Auditiva/tratamento farmacológico , Humanos , Imageamento por Ressonância Magnética/métodos
11.
J Pharm Sci ; 111(10): 2879-2887, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35667632

RESUMO

Mesoporous silica nanoparticles, with and without the inclusion of a magnetic core, were hydrothermally synthesized and employed as carrier of the antibiotic norfloxacin (NFX). The antibiotic-loaded materials were prepared by wet impregnation. Differences in drug content (and in further release profile) were directly related to changes in surface area, particle aggregation and hydrophobicity of the solids. The kinetics of NFX release has been studied in batch experiments. In all cases, more than 55% of the antibiotic was quickly desorbed during the first 5 min due to the localization of NFX on the external surface of the nanoparticles. The rest of the drug (situated inside the mesopores) was released through a diffusion-controlled transport and the rate was strongly dependent of the pH, reaching its minimum value at neutral pH. The calculated activation energy confirmed that the release was controlled by a diffusion process. Breaking of H-bonds and electrostatic and hydrophobic interactions appear to be responsible for NFX desorption from the solid surface. Such interactions increase, however, the thermal stability of the drug when the NFX and the carriers are combined. The antimicrobial activities of the drug loaded nanoparticles and the free antibiotic were compared and discussed.


Assuntos
Nanopartículas , Dióxido de Silício , Antibacterianos/química , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Excipientes , Nanopartículas/química , Norfloxacino/química , Tamanho da Partícula , Preparações Farmacêuticas , Porosidade , Dióxido de Silício/química , Eletricidade Estática
12.
Pharmaceutics ; 14(1)2022 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-35057099

RESUMO

The enormous development of nanomaterials technology and the immediate response of many areas of science, research, and practice to their possible application has led to the publication of thousands of scientific papers, books, and reports. This vast amount of information requires careful classification and order, especially for specifically targeted practical needs. Therefore, the present review aims to summarize to some extent the role of iron oxide nanoparticles in biomedical research. Summarizing the fundamental properties of the magnetic iron oxide nanoparticles, the review's next focus was to classify research studies related to applying these particles for cancer diagnostics and therapy (similar to photothermal therapy, hyperthermia), in nano theranostics, multimodal therapy. Special attention is paid to research studies dealing with the opportunities of combining different nanomaterials to achieve optimal systems for biomedical application. In this regard, original data about the synthesis and characterization of nanolipidic magnetic hybrid systems are included as an example. The last section of the review is dedicated to the capacities of magnetite-based magnetic nanoparticles for the management of oncological diseases.

13.
J Inorg Organomet Polym Mater ; 32(4): 1473-1486, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35106063

RESUMO

Novel antiviral cotton fabrics impregnated with different formulations based on Chitosan (CH), citric acid (CA), and Copper (Cu) were developed. CA was selected as a CH crosslinker agent and Cu salts as enhancers of the polymer antimicrobial activity. The characterization of the polymeric-inorganic formulations was assessed by using atomic absorption spectroscopy, X-ray diffraction, Fourier transform infrared and UV-Vis spectroscopy, as well as thermogravimetric analysis. The achieved data revealed that CuO nanoparticles were formed by means of chitosan and citric acid in the reaction media. The antiviral activity of CH-based formulations against bovine alphaherpesvirus and bovine betacoronavirus was analyzed. Cotton fabrics were impregnated with the selected formulations and the antiviral properties of such textiles were examined before and after 5 to 10 washing cycles. Herpes simplex virus type 1 was selected to analyze the antiviral activities of the functionalized cotton fabrics. The resulting impregnated textiles exhibited integrated properties of good adhesion without substantially modifying their appearance and antiviral efficacy (~ 100%), which enabling to serve as a scalable biocidal layer in protective equipment's by providing contact killing against pathogens. Thus, the results revealed a viable contribution to the design of functional-active materials based on a natural polymer such as chitosan. This proposal may be considered as a potential tool to inhibit the propagation and dissemination of enveloped viruses, including SARS-CoV-2. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s10904-021-02192-x.

14.
ChemistrySelect ; 7(37): e202202410, 2022 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-36711229

RESUMO

The extraordinary occurrence of COVID-19 by the fast expansion of viral infections has propelled particular interest in developing novel antiviral and virucidal agents to guarantee personal security. The main objective of this work is to propose novel formulations able to optimize the use of personal protection elements. In recent years, chitosan (CH) has attracted attention for being an interesting multifunctional, biodegradable, non-antigenic, non-toxic, and biocompatible natural polymer with antimicrobial properties. In this work, formulations based on a CH matrix containing silver, and Copper based nanoparticles have been developed. The novelty of this proposal is that almost liquid formulations have been reached, possessing verified properties to inhibit evolved virus such as herpes simplex type 1 (HSV-1) and bovine betacoronavirus (BCoV), the latter belonging to the same family of the well-known the well-known SARS-CoV-2. Besides antibacterial bioactivity; as well as the ability of these formulations to be easily sprayed on various surfaces, including conventional face masks, have been verified and discussed. The results presented in this contribution provide strong evidence on CH films as an ideal biosafe surface-protective for several daily used materials including the conventional face masks.

15.
Eur J Pharm Sci ; 158: 105681, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33347979

RESUMO

Colorectal cancer (CRC) is a major cause of cancer death with a high probability of treatment failure. Doxorubicin (DOXO) is an efficient antitumor drug; however, most CRC cells show resistance to its effects. Magnetic nanoparticles (MNPs) are potential cancer management tools that can serve as diagnostic agents and also can optimize and personalize treatments. This work aims to evaluate the aptitude of magnetic nanotheranostics composed of magnetite (Fe3O4) nanoparticles coated with folic acid intended to the sustained release of DOXO. The administration of DOXO by means of these MNPs resulted in the enhancement of cell death respect to the free drug administration. Chromatin compaction and cytoplasmic protrusions were observed. Mitochondrial transmembrane potential disruption and increased PARP protein cleavage confirmed apoptosis. The nanosystem was also tested as a vectoring tool by exposing it to the stimuli of a static magnetic field in vitro. CRC-related magnetic nanotechnology still remains in pre-clinical trials. In this context, this contribution expands the knowledge of the behavior of MNPs in contact with in vitro models and proposes the nanodevices studied here as potential theranostic agents for the monitoring of the progress of CRC and the evolution of its treatment.


Assuntos
Neoplasias Colorretais , Nanopartículas de Magnetita , Morte Celular , Linhagem Celular Tumoral , Neoplasias Colorretais/tratamento farmacológico , Doxorrubicina , Humanos , Fenômenos Magnéticos , Nanomedicina Teranóstica
16.
J Environ Health Sci Eng ; 19(1): 721-731, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34150269

RESUMO

PURPOSE: This study aimed to test the activity of Mn ferrite, hematin-Mn ferrite and colloidal maghemite in decomposition of Orange II (O-II) and Alizarin Red S (ARS) in model aqueous solutions. METHODS: Color removal was explored at room temperature using magnetic stirring with and without a magnetic bar, taking advantage of the solids' magnetism. Decomposition of H2O2 was also studied separately and as radicals provider in dye decomposition. Catalyst/dye solution was fixed at 10 mg/4 mL. pH and dye concentration were variable. Absorbance was measured during 120 min by UV-Vis. Reuse of catalysts was also performed. RESULTS: Azo dyes such as O-II are more resistant to oxidative removal using hydrogen peroxide than anthraquinone-like ARS. CITMD5 reduced ARS absorbance up to 71.9% when dye was less than 250 mg/L. HEM-Mn-MAG completely decolorized a 62.5 mg/L O-II solution at pH 11 while CITMD5 reached half of that conversion under the same conditions. The highest color removal in O-II/ARS mixtures was obtained with HEM-Mn-MAG, 40% absorbance reduction in 2 h. Mn-MAG is not active to remove O-II in presence of hydrogen peroxide in the 3-9 pH range at rt. CONCLUSIONS: The high activity of Mn-MAG in hydrogen peroxide decomposition may be assigned to the combination of Mn+2/Mn+3 and Fe+2/Fe+3, because the MnOx is active in the decomposition of hydrogen peroxide. Mn-MAG can be reused, preserving high activity in this reaction. Mn-based magnetic nanoparticles should be considered as inexpensive materials to treat textile wastewaters. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s40201-021-00640-x.

17.
Colloids Surf B Biointerfaces ; 198: 111460, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33246780

RESUMO

It is well known that iron oxide magnetic nanoparticles (IONPs) have many potential utilities in biomedicine due to their unique physicochemical properties. With the aim to obtain multifunctional nanoparticles with potential uses for therapy and diagnosis (nanotheranostics), IONPs were synthesized by hydrothermal synthesis assisted by mannose. Two synthetic pathways were evaluated in order to obtain IONPs with suitable properties for biomedical applications. The formulation Mag@Man/H1 presented the best characteristics in terms of size and stability. Mag@Man/H1 was evaluated as: a) drug carrier, b) antioxidant activity, c) magnetic hyperthermia, d) contrast agent for MRI. To evaluate the point a), morin, a natural flavonoid with several pharmaceutical activities, was loaded on the nanoparticles. A high percentage of drug loading was achieved. In point b) it was determined that the carrier itself possess a high activity which increased in morin loaded nanoparticles. Point c) magnetocalorimetric evaluation were carried out at several field conditions. A specific absorption rate value of 121.4 W/gFe was achieved at 52.4 kA/m and 260 kHz and 8.8 W/gFe at 4 kA/m and 100 kHz. Regarding contrast capacity (point d), the r1 value found was close to some contrast agent based on manganese. Although the measured r2 value was quite smaller than other iron oxides, the achieved effect was strong enough to produce negative contrast. From these studies, it was concluded that Mag@Man/H1 could act as a multifunctional nanoplatform for oncological diseases treatments.


Assuntos
Hipertermia Induzida , Nanopartículas , Meios de Contraste , Humanos , Imageamento por Ressonância Magnética , Magnetismo , Medicina de Precisão , Nanomedicina Teranóstica
18.
ChemMedChem ; 15(12): 1003-1017, 2020 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-32365271

RESUMO

Colorectal cancer (CRC) remains a leading cause of cancer death. Nanotechnology has focused on reaching more effective treatments. In this concern, magnetic nanoparticles (MNPs) have been studied for a wide range of biomedical applications related to CRC, such as diagnostic imaging, drug delivery and thermal therapy. However, limited research is currently found in the open literature that refers to nanosystems combining all these mentioned areas (theranostics). When developing nanosystems intended as theranostics applied to CRC, possible variations between patients must be considered. Therefore, multiple in vitro assays are required as guidance for future preclinical and clinical trials. The objective of this contribution is to evaluate the available and recent literature regarding the interactions of MNP and CRC models, aiming to critically analyze the information given by the commonly used assays and evaluate the data provided by each one with a view to implementing this novel technology in CRC diagnostics and therapy.


Assuntos
Técnicas de Química Analítica/métodos , Neoplasias Colorretais/metabolismo , Nanopartículas de Magnetita/química , Medicina de Precisão/métodos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Modelos Biológicos , Estresse Oxidativo/efeitos dos fármacos
19.
Environ Sci Pollut Res Int ; 27(1): 861-872, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31814073

RESUMO

Hydrogels (HGs) based on gelatin and crosslinked with gum Arabic have been prepared by the thaw-freezing method, employing two different concentrations of gum Arabic (15 and 50% w/w). Magnetic gels or ferrogels (FGs) were prepared by applying the breath in method to incorporate iron oxide magnetic nanoparticles to the HG matrix. The obtained HG and FG were characterized by XRD, FTIR, and SEM, and the FG composition was estimated by atomic absorption spectroscopy in terms of Fe content. The adsorption of crude oil onto HG and FG was explored achieving very satisfactory results. FG was regenerated by washing with toluene, maintaining efficiency of almost 90% after the fourth cycle. Equilibrium studies were performed to determine the capacity of the prepared FG for adsorption of crude oil from seawater synthetic solutions. The experiments were carried out as a function of different initial concentrations of oil residue (24 to 240 mg/L) exploring different contact times. Equilibrium data were found to fit very well with the Sips models. The kinetic data adsorption of oil onto the FG-15 was better fitted by a pseudo-second-order kinetic indicating that at the initial stages of adsorption, external mass transfer could control the whole rate of the crude oil uptake while intraparticle diffusion controlled the global rate of adsorption at later stages. The obtained results showed that the FG prepared by employing 15% of gum Arabic as the crosslinker (FG-15) has a high removal efficiency of crude oil reaching 1.53 g/g of FG at pH 5.5 and 0.59 g/g for oil/water emulsions in the order of 0.1 g/L. The magnetic properties extend its application. The reached data suggest that the materials presented here may be useful to further the design of systems or devices intended for the remediation of petroleum spills and/or its derivatives in marine water as well as other surfaces such as polluted rocks or soil.


Assuntos
Recuperação e Remediação Ambiental/métodos , Poluição por Petróleo , Petróleo/análise , Poluentes Químicos da Água/química , Adsorção , Emulsões/química , Géis/química , Concentração de Íons de Hidrogênio , Cinética , Água do Mar , Solo , Água/química , Purificação da Água/métodos
20.
Environ Sci Pollut Res Int ; 25(28): 28185-28194, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30073594

RESUMO

Magnetic nanoparticles (MNPs), based on iron oxide (magnetite) and ferrogel of gelatin and MNPs, were employed as efficient tools for the removal of heavy metals and nutrients from water samples from Bahia Blanca estuarine (BBE). An exhaustive adsorption performance of Cu, NO3-, and NO2- was conducted in batch using model solutions aiming to adjust the adsorption conditions. Adsorption studies using water simulating the real samples were also performed. Both kinds of nanomaterials demonstrated an efficiency between 60 and 80%, and 85% for the removal of heavy metals and NO3- and NO2-, respectively. Similar adsorption assays were performed using BBE water samples, employing the experimental conditions explored with model and simulated water. The reached efficiency was 30 and 45% for heavy metal and nutrient removal, respectively, using nanoparticles; meanwhile, ferrogels displayed a removal capacity around 50-60%. The nanoparticles showed structural instability by the leaching of iron to the medium after the adsorption processes. Ferrogels remained almost inalterable in terms of their integrity during the adsorption time. These materials showed satisfactory perspectives regarding their reuse possibilities. They were used for almost five repeated cycles of adsorption without losing efficiency on the adsorption. The results of this study suggest that MNPs and FGs appear as versatile and promising materials that may be considered as valid alternatives to the actual tools for the remediation of real water samples.


Assuntos
Gelatina/química , Nanopartículas de Magnetita/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Adsorção , Géis , Ferro/química , Fenômenos Magnéticos , Metais Pesados/química , Nanotecnologia , Nitratos/química , Nitritos/química
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