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2.
Chemosphere ; 341: 140000, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37652244

RESUMO

Microplastics (MPs) have become the major global concern due to their adverse effects on the environment, human health, and hygiene. These complex molecules have numerous toxic impacts on human well-being. This review focuses on the methods for chemically quantifying and identifying MPs in real-time samples, as well as the detrimental effects resulting from exposure to them. Biopolymers offer promising solutions for reducing the environmental impact caused by persistent plastic pollution. The review also examines the significant progress achieved in the preparation and modification of various biobased polymers, including polylactic acid (PLA), poly(ε-caprolactone) (PCL), lignin-based polymers, poly-3-hydroxybutyrate (PHB), and poly(hydroxyalkanoates) (PHA), which hold promise for addressing the challenges associated with unplanned plastic waste disposal.


Assuntos
Polímeros , Eliminação de Resíduos , Humanos , Microplásticos/toxicidade , Plásticos/química , Poluição Ambiental
3.
Adv Mater ; 35(48): e2301589, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37435972

RESUMO

Tritium is a sustainable next-generation prime fuel for generating nuclear energy through fusion reactions to fulfill the increasing global energy demand. Owing to the scarcity-high demand tradeoff, tritium must be bred inside a fusion reactor to ensure sustainability and must therefore be separated from its isotopes (protium and deuterium) in pure form, stored safely, and supplied on demand. Existing multistage isotope separation technologies exhibit low separation efficiency and require intensive energy inputs and large capital investments. Furthermore, tritium-contaminated heavy water constitutes a major fraction of nuclear waste, and accidents like the one at Fukushima Daiichi leave behind thousands of tons of diluted tritiated water, whose removal is beneficial from an environmental point of view. In this review, the recent progress and main research trends in hydrogen isotope storage and separation by focusing on the use of metal hydride (e.g., intermetallic, and high-entropy alloys), porous (e.g., zeolites and metal organic frameworks (MOFs)), and 2-D layered (e.g., graphene, hexagonal boron nitride (h-BN), and MXenes) materials to separate and store tritium based on their diverse functionalities are discussed. Finally, the challenges and future directions for implementing tritium storage and separation are summarized in the reviewed materials.

4.
ChemSusChem ; 16(21): e202300730, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37485991

RESUMO

Improving the energy share of renewable energy technologies is the only solution to reduce greenhouse gas emissions and air pollution. The high-performing green battery energy storage technologies are critical for storing energy to address the intermittent nature of renewable energy resources. In recent years, aqueous batteries, particularly Zn-ion batteries (ZIBs), have achieved and shown great potential for stationary energy storage systems owing to their low cost and safer operation. However, the practical applications of the ZIBs have significantly been impeded due to the gap between the breakthroughs achieved in academic research and industrial developments. The present review discusses the ZIB's advantages, possibilities, and shortcomings for stationary energy storage systems. The Review begins with a brief introduction to the ZIBs and their charge storage mechanisms based on the structural properties of cathode materials. The scientific and technical challenges that obstruct the commercialization of the ZIBs are discussed in detail concerning their impact on accelerating the utilization of the ZIBs for real-life applications. The final section highlights the outlook on research in this flourishing field.

5.
Chemosphere ; 336: 139256, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37331664

RESUMO

Global demand for lithium (Li) resources has dramatically increased due to the demand for clean energy, especially the large-scale usage of lithium-ion batteries in electric vehicles. Membrane capacitive deionization (MCDI) is an energy and cost-efficient electrochemical technology at the forefront of Li extraction from natural resources such as brine and seawater. In this study, we designed high-performance MCDI electrodes by compositing Li+ intercalation redox-active Prussian blue (PB) nanoparticles with highly conductive porous activated carbon (AC) matrix for the selective extraction of Li+. Herein, we prepared a series of PB-anchored AC composites (AC/PB) containing different percentages (20%, 40%, 60%, and 80%) of PB by weight (AC/PB-20%, AC/PB-40%, AC/PB-60%, and AC/PB-80%, respectively). The AC/PB-20% electrode with uniformly anchored PB nanoparticles over AC matrix enhanced the number of active sites for electrochemical reaction, promoted electron/ion transport paths, and facilitated abundant channels for the reversible insertion/de-insertion of Li+ by PB, which resulted in stronger current response, higher specific capacitance (159 F g-1), and reduced interfacial resistance for the transport of Li+ and electrons. An asymmetric MCDI cell assembled with AC/PB-20% as cathode and AC as anode (AC//AC-PB20%) displayed outstanding Li+ electrosorption capacity of 24.42 mg g-1 and a mean salt removal rate of 2.71 mg g min-1 in 5 mM LiCl aqueous solution at 1.4 V with high cyclic stability. After 50 electrosorption-desorption cycles, 95.11% of the initial electrosorption capacity was retained, reflecting its good electrochemical stability. The described strategy demonstrates the potential benefits of compositing intercalation pseudo capacitive redox material with Faradaic materials for the design of advanced MCDI electrodes for real-life Li+ extraction applications.


Assuntos
Carvão Vegetal , Lítio , Carvão Vegetal/química , Eletrodos , Oxirredução
6.
Nanomaterials (Basel) ; 12(15)2022 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-35893490

RESUMO

In recent times, upconversion nanomaterials with mesoporous hollow structures have gained significant interest as a prospective nano-platform for cancer imaging and therapeutic applications. In this study, we report a highly biocompatible YVO4:1Er3+/10Yb3+ upconversion mesoporous hollow nanospheriods (YVO4:Er3+/Yb3+ UC-MHNSPs) by a facile and rapid self-sacrificing template method. The Rietveld analysis confirmed their pure phase of tetragonal zircon structure. Nitrogen adsorption-desorption isotherms revealed the mesoporous nature of these UC-MHNSPs and the surface area is found to be ~87.46 m2/g. Under near-infrared excitation (980 nm), YVO4:Er3+/Yb3+ UC-MHNSPs showed interesting color tunability from red to green emission. Initially (at 0.4 W), energy back transfer from Er3+ to Yb3+ ions leads to the strong red emission. Whereas at high pump powers (1 W), a fine green emission is observed due to the dominant three-photon excitation process and traditional energy transfer route from Er3+ to Yb3+ ions. The bright red light from the membrane of HeLa cells confirmed the effective cellular uptake of YVO4:Er3+/Yb3+ UC-MHNSPs. The resonant decrease in cell viability on increasing the concentration of curcumin conjugated YVO4:Er3+/Yb3+ UC-MHNSPs established their excellent antitumor activity. Therefore, the acquired results indicate that these YVO4:Er3+/Yb3+ UC-MHNSPs are promising drug carriers for bioimaging and various therapeutic applications.

7.
Pharmacol Ther ; 232: 107994, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34571111

RESUMO

Helicobacter pylori (H. pylori) is a major causative agent of chronic gastritis, gastric ulcer and gastric carcinoma. H. pylori cytotoxin associated antigen A (CagA) plays a crucial role in the development of gastric cancer. Gastric cancer is associated with glycosylation alterations in glycoproteins and glycolipids on the cell surface. H. pylori cytotoxin associated antigen A (CagA) plays a significant role in the progression of gastric cancer through post-translation modification of fucosylation to develop gastric cancer. The involvement of a variety of sugar antigens in the progression and development of gastric cancer has been investigated, including type II blood group antigens. Lewis Y (LeY) is overexpressed on the tumor cell surface either as a glycoprotein or glycolipid. LeY is a difucosylated oligosaccharide, which is catalyzed by fucosyltransferases such as FUT4 (α1,3). FUT4/LeY overexpression may serve as potential correlative biomarkers for the prognosis of gastric cancer. We discuss the various aspects of H. pylori in relation to fucosyltransferases (FUT1-FUT9) and its fucosylated Lewis antigens (LeY, LeX, LeA, and LeB) and gastric cancer. In this review, we summarize the carcinogenic effect of H. pylori CagA in association with LeY and its synthesis enzyme FUT4 in the development of gastric cancer as well as discuss its importance in the prognosis and its inhibition by combination therapy of anti-LeY antibody and celecoxib through MAPK signaling pathway preventing gastric carcinogenesis.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Neoplasias Gástricas , Crime , Fucosiltransferases/metabolismo , Infecções por Helicobacter/complicações , Humanos , Antígenos do Grupo Sanguíneo de Lewis/metabolismo , Neoplasias Gástricas/metabolismo
8.
J Hazard Mater ; 421: 126775, 2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-34358971

RESUMO

Hydroquinone (HQ) and catechol (CC) are the two major dihydroxybenzene isomers, are considered one of the toxic pollutants in wastewater, which often coexisted and impede each other during sample identification. For practical analysis and simultaneous detection of HQ and CC in wastewater, we fabricate a hybrid electrochemical sensor with electrospun one-dimensional (1D) MnMoO4 nanofibers coupled with a few-layered exfoliated two-dimensional (2D) MXene. The facilitated abundant defective edges of 1D MnMoO4 and 2D MXene nanoarchitecture accelerated the effect of synergistic signal amplification and exhibited high electrocatalytic activity towards the oxidation of hydroquinone and catechol. MnMoO4-MXene-GCE showed oxidation potentials of 0.102 V and 0.203 V for hydroquinone and catechol, respectively. It revealed the distinguished and simultaneous detection range of 0.101 V with a strong anodic peak current. Noteworthily, the proposed 1D-2D hybridized MnMoO4-MXene-GCE sensor exhibited a wide linear response from 5 nM to 65 nM for hydroquinone and catechol. Moreover, it showed a low detection limit of 0.26 nM and 0.30 nM for HQ and CC with high stability, respectively. The feasible 1D-2D MnMoO4-MXene nanocomposite-based biosensor effectively detected hydroquinone and catechol in hazardous water pollutants using the differential pulse voltammetric technique with recovery values.


Assuntos
Técnicas Biossensoriais , Nanocompostos , Nanofibras , Eletrodos , Águas Residuárias
9.
Small ; 18(7): e2103326, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34889512

RESUMO

Developing highly efficient noble-metal-free electrocatalysts with a scalable and environmentally friendly synthesis approach remains a challenge in the field of electrocatalytic water splitting. To overcome this problem, self-supported fluorine-modified 2D ultrathin nickel hydroxide (F-Ni(OH)2 ) nanosheets (NSs) for the oxygen evolution reaction (OER) and urea oxidation reaction (UOR) are prepared with a scalable and ascendant one-step synthesis route. The enhanced redox activity, electrical conductivity and a great number of exposed active sites of the heterogeneous catalysts improve charge migration for the electrocatalytic reactions. The density of states of the d orbitals of the Ni atoms significantly increases near the Fermi level, thereby indicating that the Ni atoms near the F-dopants promote electrical conduction in the Ni(OH)2 monolayer. The F-Ni(OH)2 electrocatalyst exhibits notable OER and UOR activity with onset potentials of 1.43 and 1.16 V versus RHE, respectively required to reach 10 mA cm-2 , which are comparable to those of commercial noble-metal-based electrocatalysts. With RuCo-OH nanospheres, the settled F-Ni(OH)2 ||RuCo-OH cell requires merely 1.55 and 1.37 V to reach 10 mA cm-2 with superb durability for 24 h in overall water and urea electrolysis, respectively. Overall, high-quality, and efficient noble-metal-free electrocatalysts for overall water and urea electrolysis can be prepared with a simple, scalable, and reproducible preparation method.

10.
Ecotoxicol Environ Saf ; 228: 113021, 2021 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-34856486

RESUMO

Fenitrothion (FT) is a toxic phosphorothioate insecticide that can easily contaminate aquatic environments, leading to a detrimental effect on the aquatic species and harmful endocrine disrupter effects on human health. Therefore, it is vital to develop a reliable methodology for the accurate and precise real-time sensing of carcinogenic FT in water samples at trace concentration to ensure environmental safety. We aim to fabricate the low-cost VS2-attached reduced graphene oxide (RGO) sheets via a simple hydrothermal approach. It was further applied for the rapid and accurate sensing of toxic FT. The VS2/RGO-composite delivers a more favorable microenvironment for the rapid electrocatalytic sensing performance towards toxic FT reduction than the VS2 and RGO modified electrodes. The electron transfer rate constant (ks) and the saturating absorption capacity (Γ) value of FT was evaluated to be 1.52 s-1 and 2.18 × 10-10 mol cm-2, respectively. The constructed sensor exhibits a wide linear relationship after amperometry between the cathodic current densities and the concentrations of FT in the range of 5-90 nM and high sensitivity (5.569 µA nM-1 cm-2); moreover, the detection limit was 0.07 nM (S/N = 3). The fabricated sensor has excellent anti-interference ability and reproducibility for the direct sensing of FT in river water, seawater, and lake water samples with acceptable recoveries. It is a promising sensing device for in-situ quantification of FT in agricultural products and ecological systems.

11.
J Hazard Mater ; 418: 126315, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34329027

RESUMO

In this work, we prepared two-dimensional (2D) stack-structured aminopropylIsobutyl polyhedral oligomeric silsesquioxane (POSS-NH2) intercalated titanium carbide (Ti3C2Tx) MXene material (Ti3C2Tx/POSS-NH2) using a post-intercalation strategy as a potential adsorbent for the removal of cesium (Cs+) and strontium (Sr2+) ions from aqueous solutions. Ti3C2Tx/POSS-NH2 exhibited unprecedented adsorption capacities of 148 and 172 mg g-1 for Cs+ and Sr2+ ions, respectively. Batch adsorption experimental data well fitted the Freundlich isotherm model, which revealed multilayer adsorption of Cs+ and Sr2+ ions onto heterogeneous -OH, -F, -O, and -NH2 adsorption sites of Ti3C2Tx/POSS-NH2 with different energies. Ti3C2Tx/POSS-NH2 exhibited rapid Cs+/Sr2+ ions adsorption kinetics and attained equilibrium within 30 min. Also, Ti3C2Tx/POSS-NH2 exhibited recyclable capability over three cycles and remarkable selectivities of 89% and 93% for Cs+ and Sr2+ ions, respectively, in the presence of co-existing mono- and divalent cations. We suggest the high adsorption capacity of Ti3C2Tx/POSS-NH2 might be due to the synergistic effects of (i) increased inter-lamellar distance between Ti3C2Tx galleries due to POSS-NH2 intercalation, enabling diffusion and encapsulation of large numbers of Cs+/Sr2+ ions, (ii) strong complexation of amine (-NH2) groups of POSS-NH2 with Cs+/Sr2+ ions, and (iii) the presence of large numbers of heterogeneous surface functional groups (e.g., -OH, -F, and -O), which resulted in the adsorptions of Cs+/Sr2+ ions through electrostatic, ion exchange, and surface complexation mechanisms. Given the extraordinary adsorption capacities observed, intercalation appears to be a promising strategy for the effective removal of radioactive Cs+ and Sr2+ ions from aqueous media.

12.
Mikrochim Acta ; 188(3): 106, 2021 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-33651208

RESUMO

Unique Ni2CoS4-carbon nanofiber (CNF) composite nanostructures were fabricated using a simple electrospinning-assisted hydrothermal route and used for the rapid and accurate electrochemical oxidation of glucose in real samples at the trace level. Electrochemical impedance spectroscopy and cyclic voltammetry of unmodified and modified electrodes revealed low charge-transfer resistance and the excellent electrocatalytic sensing of glucose when using the Ni2CoS4-CNF at a low potential due to the combined benefits of the highly conductive Ni2Co2S4 anchored to the large surface area of the CNFs. Amperometric analysis of the fabricated sensor has shown an extremely low limit of detection (0.25 nM) and a large linear range (5-70 nM) for glucose at a working potential of 0.54 V (vs. Hg/HgO). The practicability of the Ni2CoS4-CNF for use in glucose determination was tested withl human saliva, blood plasma, and fruit juice samples. The Ni2CoS4-CNF/GCE showed acceptable recovery values for human saliva (99.1-100.8%), blood plasma (98.6-101.5%), and fruit juice (95.1-105.7%) samples. The proposed sensor also exhibited outstanding electroanalytical characteristics for glucose oxidation in these samples, including reusability, repeatability, and interference resistance, even in the presence of other biological substances and organic and inorganic metal ions.


Assuntos
Glicemia/análise , Técnicas Eletroquímicas/métodos , Nanocompostos/química , Nanofibras/química , Glicemia/química , Carbono/química , Cobalto/química , Técnicas Eletroquímicas/instrumentação , Eletrodos , Sucos de Frutas e Vegetais/análise , Humanos , Limite de Detecção , Níquel/química , Oxirredução , Reprodutibilidade dos Testes , Saliva/química , Sulfetos/química
13.
Food Chem ; 348: 128936, 2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-33508604

RESUMO

The excessive use of food additives in manufactured food products negatively affects their quality and potentially impacts human health. In the present study, a composite consisting of gold nanoparticles decorated on tungsten carbide (AuNP-WC) was successfully fabricated using a facile and cost-effective ultrasonication technique. Compared to a bare glassy carbon electrode (GCE), AuNP-GCE, and WC-GCE, the AuNP-WC-GCE demonstrated excellent sensing performance for tert-butylhydroquinone (TBHQ) when used as an electrocatalyst in 0.05 M phosphate buffer solution (PBS), with a low working potential and a high peak current. In particular, the composite was able to detect the oxidation of TBHQ within a linear concentration range of 5 to 75 nM, with an extremely low detection limit of 0.20 nM. The practicability of the sensor was also assessed in the analysis of TBHQ in real samples of soybean oil, blended oil, and red wine, with satisfactory recovery rates obtained.


Assuntos
Ouro/química , Hidroquinonas/análise , Limite de Detecção , Nanopartículas Metálicas/química , Nanocompostos/química , Nanotecnologia , Compostos de Tungstênio/química , Carbono/química , Técnicas de Química Sintética , Eletrodos , Humanos , Oxirredução
14.
Langmuir ; 37(5): 1682-1696, 2021 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-33492958

RESUMO

The beguiling world of functional polymers is dominated by thermoresponsive polymers with unique structural and molecular attributes. Limited work has been reported on the protein-induced conformational transition of block copolymers; furthermore, the literature lacks a clear understanding of the influence of proteins on the phase behavior of thermoresponsive copolymers. Herein, we have synthesized poly(N-isopropylacrylamide)-b-poly(N-vinylcaprolactam) (PNIPAM-b-PNVCL) by RAFT polymerization using N-isopropylacrylamide and N-vinylcaprolactam. Furthermore, using various biophysical techniques, we have explored the effect of cytochrome c (Cyt c), myoglobin (Mb), and hemoglobin (Hb) with varying concentrations on the aggregation behavior of PNIPAM-b-PNVCL. Absorption and steady-state fluorescence spectroscopy measurements were performed at room temperature to examine the copolymerization effect on fluorescent probe binding and biomolecular interactions between PNIPAM-b-PNVCL and proteins. Furthermore, temperature-dependent fluorescence spectroscopy and dynamic light scattering studies were performed to get deeper insights into the lower critical solution temperature (LCST) of PNIPAM-b-PNVCL. Small-angle neutron scattering (SANS) was also employed to understand the copolymer behavior in the presence of heme proteins. With the incorporation of proteins to PNIPAM-b-PNVCL aqueous solution, LCST has been varied to different extents owing to the preferential, molecular, and noncovalent interactions between PNIPAM-b-PNVCL and proteins. The present study can pave new insights between heme proteins and block copolymer interactions, which will help design biomimetic surfaces and aid in the strategic fabrication of copolymer-protein bioconjugates.


Assuntos
Hemeproteínas , Resinas Acrílicas , Transição de Fase , Polímeros , Temperatura
15.
J Hazard Mater ; 408: 124914, 2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33360698

RESUMO

The improper disposal in agricultural and industrial wastewater leads to high NO2- concentrations in the aquatic environment, which can cause cancer in humans and animals; thus, their quick and accurate detection is urgently needed to ensure public health and environmental safety. In this study, a reliable and selective electrochemical sensor consisting of Pd-Cu nanospheres (NSs) supported on molybdenum carbide was prepared via simple ultrasonication. Then, a glassy carbon electrode was realized using this composite (Pd-Cu-Mo2C-modified GCE) to test its electrocatalytic sensing for NO2- in a 0.1 M phosphate-buffered solution (PBS) solution via cyclic voltammetry and amperometry; at a low oxidation potential, the anodic peak current of NO2- detected by this electrode was significantly higher than that of its unmodified and other modified electrodes. The sensor showed a broad linear response in the 5-165-nM NO2- concentration range, with a low detection limit (0.35 nM in 0.1 M PBS) and high sensitivity (3.308 µAnM-1 cm-2). Moreover, the fabricated electrode was successfully applied for detecting nitrites in sausages, river water, and milk, showing also good recovery.

16.
Pharmacol Res ; 163: 105313, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33246173

RESUMO

Understanding how the natural products structural diversity interacts with cellular metabolism and infectious disease targets remains a challenge. Inflammation is an important process in the human healing response in which the tissues respond to injuries induced by many agents, including pathogens. In recent years, several drugs derived from plant products have been developed, and current drug research is actively investigating the pharmacotherapeutic role of natural products in advanced multimodal inflammatory disease targeting. Sugiol, a diterpenoid, can act as an antimicrobial, antioxidant, anti-inflammatory, anti-carcinoma, antiviral, and cardiovascular agent. Until now, there have been no updates on the pharmacotherapeutic advancement of sugiol. Herein, we correlate the diverse molecular pathways in disease prevention involving sugiol. We also discuss the origins of its structural diversity and summarize new research directions toward exploring its novel effective future uses. Despite much evidence of its efficacy and safety, the sugiol has not yet been approved as a therapeutic agent due to its low bioavailability, and insolubility in an aqueous environment. The aim of this review is to renew and update noteworthy information on the pharmacotherapeutic characteristics of sugiol to approach different advanced strategies employed in the context of natural nurturing-based biomedicine.


Assuntos
Diterpenos/farmacologia , Diterpenos/uso terapêutico , Animais , Anti-Infecciosos/farmacologia , Anti-Infecciosos/uso terapêutico , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Humanos
17.
J Hazard Mater ; 399: 122868, 2020 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-32531674

RESUMO

Environmental hazards caused by chloramphenicol has attained special attention. Fast, accurate and reliable detection of chloramphenicol in foodstuffs and water samples is of utmost importance. Herein, we developed a g-C3N4/MnWO4 composite for the selective and sensitive detection of chloramphenicol. Successful fabrication of g-C3N4/MnWO4 composite was verified by using scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectroscopy, Fourier transform infrared spectroscopy (FT-IR), x-ray diffraction (XRD) and x-ray photo electron spectroscopy (XPS) techniques. Electrochemical characteristics were evaluated by using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and differential pulse voltammetry (DPV). The g-C3N4/MnWO4 modified glassy carbon electrode has shown the highest electrocatalytic activity towards chloramphenicol with a decreased reduction potential of -0.547 V and increased cathodic peak current. The developed sensor has shown excellent performance for the detection of chloramphenicol with a sensitivity of 0.9986 µA nM-1 cm-2 and LOD of 1.03 nM in a broad linear range of 4.0-71 nM. In addition, the fabricated sensor has achieved anti-interference ability, good stability, excellent repeatability and remarkable reproducibility for the detection of chloramphenicol. The fabricated sensor applied for the determination of chloramphenicol in milk, human blood serum and sewage samples, in which significant and satisfactory results were achieved.


Assuntos
Cloranfenicol , Técnicas Eletroquímicas , Animais , Carbono , Eletrodos , Grafite , Humanos , Limite de Detecção , Compostos de Nitrogênio , Reprodutibilidade dos Testes , Espectroscopia de Infravermelho com Transformada de Fourier
18.
J Food Drug Anal ; 26(4): 1201-1214, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30249319

RESUMO

The rapid development of nanotechnology has transformed many domains of food science, especially those that involve the processing, packaging, storage, transportation, functionality, and other safety aspects of food. A wide range of nanostructured materials (NSMs), from inorganic metal, metal oxides, and their nanocomposites to nano-organic materials with bioactive agents, has been applied to the food industry. Despite the huge benefits nanotechnology has to offer, there are emerging concerns regarding the use of nanotechnology, as the accumulation of NSMs in human bodies and in the environment can cause several health and safety hazards. Therefore, safety and health concerns as well as regulatory policies must be considered while manufacturing, processing, intelligently and actively packaging, and consuming nano-processed food products. This review aims to provide a basic understanding regarding the applications of nanotechnology in the food packaging and processing industries and to identify the future prospects and potential risks associated with the use of NSMs.


Assuntos
Conservação de Alimentos/métodos , Nanotecnologia/métodos , Manipulação de Alimentos/instrumentação , Manipulação de Alimentos/métodos , Conservação de Alimentos/instrumentação , Inocuidade dos Alimentos , Nanoestruturas/química
19.
Biosens Bioelectron ; 117: 597-604, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-30005379

RESUMO

We report an electrochemical sensor based on three-dimensional porous amorphous carbon (3DPAC) for the sensitive and selective determination of gallic acid (GA). The tailor-made carbon was prepared via salt-templating in which the organic molecular precursor, i.e., glucose, was simply ground and carbonized with a eutectic mixture of LiBr and KBr at 800 °C in an inert atmosphere. Salt removal from the carbon-salt mixture with water yielded 3DPAC with a hierarchical porous structure and oxygen-containing functional groups. When employed as an electrochemical sensor, 3DPAC exhibited remarkable sensitivity (0.1045 µA pM-1 cm-2) with a lower detection limit of 0.434 pM at a signal-to-noise ratio of 3 and a linear response up to 1-150 pM for determination of GA. Under optimized test conditions, 3DPAC showed a superior peak current response for GA as compared to the glassy carbon electrode. In addition, ascorbic, uric, and caffeic acids did not interfere with the voltammetric detection of GA in terms of selectivity, stability, and repeatability. We envision that 3DPAC can provide a promising platform for the development of electrochemical sensors.


Assuntos
Técnicas Biossensoriais/métodos , Carbono/química , Técnicas Eletroquímicas , Ácido Gálico/análise , Sais/química , Técnicas Biossensoriais/instrumentação , Eletrodos , Limite de Detecção
20.
Mar Drugs ; 16(6)2018 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-29882898

RESUMO

Current trends in the application of nanomaterials are emerging in the nano-biotechnological sector for development of medicines. Cyanobacteria (blue-green algae) are photosynthetic prokaryotes that have applications to human health and numerous biological activities as dietary supplements. Cyanobacteria produce biologically active and chemically diverse compounds such as cyclic peptides, lipopeptides, fatty acid amides, alkaloids, and saccharides. More than 50% of marine cyanobacteria are potentially exploitable for the extraction of bioactive substances, which are effective in killing cancer cells by inducing apoptotic death. The current review emphasizes that not even 10% of microalgal bioactive components have reached commercialized platforms due to difficulties related to solubility. Considering these factors, they should be considered as a potential source of natural products for drug discovery and drug delivery approaches. Nanoformulations employing a wide variety of nanoparticles and their polymerized forms could be an emerging approach to the development of new cancer drugs. This review highlights recent research on microalgae-based medicines or compounds as well as their biomedical applications. This review further discusses the facts, limitations, and commercial market trends related to the use of microalgae for industrial and medicinal purposes.


Assuntos
Antineoplásicos/uso terapêutico , Fatores Biológicos/uso terapêutico , Cianobactérias/metabolismo , Sistemas de Liberação de Medicamentos/métodos , Microalgas/metabolismo , Neoplasias/tratamento farmacológico , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Fatores Biológicos/química , Fatores Biológicos/isolamento & purificação , Biotecnologia/métodos , Biotecnologia/tendências , Comércio/tendências , Composição de Medicamentos/métodos , Descoberta de Drogas/métodos , Descoberta de Drogas/tendências , Estabilidade de Medicamentos , Humanos , Nanopartículas/química , Nanopartículas/uso terapêutico , Nanotecnologia/métodos , Nanotecnologia/tendências , Solubilidade
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