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1.
Small ; 20(25): e2311945, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38196051

RESUMO

Hybrid ion capacitors (HIC) are receiving a lot of attention due to their potential to achieve high energy and power densities, but they remain insufficient. It is imperative to explore outstanding and environmentally benign electrode materials to achieve high-performing HIC systems. Here, a unique boron carbon nitride (BCN)-based HIC system that comprises a microporous BCN structure and Fe1-xS nanoparticle incorporated BCN nanosheets (BNF) as cathode and anode, respectively is reported. The BNF is prepared through a facile one-pot calcination process using dithiooxamide (DTO), boric acid, and iron source. In situ, crystal growth of Fe1-xS facilitates the formation of BCN structure through the creation of holes/defects in the polymeric structure. The first principle density functional (DFT) theory simulations demonstrate the structural and electronic properties of the hybrid of BCN and Fe1-xS as compelling anode materials for HIC applications. The DFT calculations reveal that both BCN and BNF structures have excellent metallic characters with Li+ storage capacities of 128.4 and 1021.38 mAh g-1 respectively. These findings are confirmed experimentally where the BCN-based HIC system delivers exceptional energy and power densities of 267.5 Wh kg-1/749.5 W kg-1 toward Li+ storage, which outweighs previous HIC performances and demonstrates favorable performance for Li+ and Na+ storages.

2.
Langmuir ; 40(18): 9732-9740, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38668749

RESUMO

Metal-organic frameworks (MOFs) are highly regarded as valuable adsorbent materials in materials science, particularly in the field of CO2 capture. While numerous single-metal-based MOFs have demonstrated exceptional CO2 adsorption capabilities, recent advancements have explored the potential of bimetallic MOFs for enhanced performance. In this study, a CuCe-BTC MOF was synthesized through a straightforward hydrothermal method, and its improved properties, such as high surface area, smaller pore size, and larger pore volume, were compared with those of the bare Ce-BTC. The impact of the Cu/Ce ratio (1:4, 1:2, 1:1, and 3:2) was systematically investigated to understand how adding a second metal influences the CO2 adsorption performance of the Ce-BTC MOF. Various characterization techniques, including scanning electron microscopy, transmission electron microscopy, powder X-ray diffraction, thermogravimetric analysis, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, and N2 BET surface area analysis, were employed to assess the physical and chemical properties of the bare Ce-BTC and CuCe-BTC samples. Notably, CuCe-BTC-1:2 exhibited superior surface area (133 m2 g-1), small pore size (3.3 nm), and large pore volume (0.14 cm3 g-1) compared to the monometallic Ce-BTC. Furthermore, CuCe-BTC-1:2 demonstrated a superior CO2 adsorption capacity (0.74 mmol g-1), long-term stability, and good CO2/N2 selectivity. This research provides valuable insights into the design of metal-BTC frameworks and elucidates how introducing a second metal enhances the properties of the monometallic Ce-BTC-MOF, leading to improved CO2 capture performance.

3.
Org Biomol Chem ; 22(16): 3340, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38607296

RESUMO

Correction for 'Recent progress of core-substituted naphthalenediimides: highlights from 2010' by Sheshanath V. Bhosale et al., Org. Biomol. Chem., 2012, 10, 6455-6468, https://doi.org/10.1039/C2OB25798J.

4.
Inorg Chem ; 62(23): 8846-8862, 2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-37254744

RESUMO

Treatment of the bis(chelate) complexes trans-[M(κ2-2-C6F4PPh2)2] (trans-1M; M = Ni, Pt) and cis-[Pt(κ2-2-C6F4PPh2)2] (cis-1Pt) with equimolar amounts or excess of PMe3 solution gave complexes of the type [(Me3P)xM(2-C6F4PPh2)2] (x = 2: 2Ma, 2Mb x = 1: 3Ma, 3Mb; M = Ni, Pt). The reactivity of complexes of the type 2M and 3M toward monovalent coinage metal ions (M' = Cu, Ag, Au) was investigated next to the reaction of 1M toward [AuCl(PMe3)]. Four different complex types [(Me3P)2M(µ-2-C6F4PPh2)2M'Cl] (5MM'; M = Ni, Pt; M' = Cu, Ag, Au), [(Me3P)M(κ2-2-C6F4PPh2)(µ-2-C6F4PPh2)M'Cl]x (x = 1: 6MM'; M = Pt; M' = Cu, Au; x = 2: 6PtAg), head-to-tail-[(Me3P)ClM(µ-2-C6F4PPh2)2M'] (7MM'; M = Ni, Pt; M' = Au), and head-to-head-[(Me3P)ClM(µ-2-C6F4PPh2)2M'] (8MM'; M = Ni, Pt; M' = Cu, Ag, Au) were observed. Single-crystal X-ray analyses of complexes 5-8 revealed short metal-metal separations (2.7124(3)-3.3287(7) Å), suggestive of attractive metal-metal interactions. Quantum chemical calculations (atoms in molecules (AIM), electron localization function (ELF), non-covalent interaction (NCI), and natural bond orbital (NBO)) gave theoretical support that the interaction characteristics reach from a pure attractive non-covalent to an electron-shared (covalent) character.

5.
Chem Rev ; 120(15): 7551-7591, 2020 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-32662987

RESUMO

The past decade has seen a diverse range of breakthrough inventions that are derived from gold complexes, including the application of aurophilic interactions in the preparation of stimuli-responsive materials. Examples of these gold-based materials include aurophilicity-induced metallogelators, mechanochromic, thermochromic, vapochromic, and solvatochromic luminescent compounds, as well as sensory materials for the detection of metal ions. Sophisticated properties of gold complexes with Au···Au contacts have been explored at the edge of several disciplines including chemistry, crystallography, molecular engineering and advanced materials. As science paves its way to innovation, cross-disciplinary research moves from being a luxury to becoming a necessity. Development of the concept of aurophilicity and its use in designing novel materials is a true example of innovation on a multidisciplinary platform. As miniaturization continues to influence the next generation of technological advancement, using the properties of molecules as chemical tools to enable such developments becomes extremely important. In this Review, recent examples of gold complexes which exhibit a response to external stimuli have been collected and some of their potential applications discussed for selected cases.

6.
Chem Soc Rev ; 50(7): 4564-4605, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33595011

RESUMO

Ethene is a commodity chemical of great importance for manufacturing diverse consumer products, whose synthesis via crude oil steam cracking is one of the most energy-intensive processes in the petrochemical industry. Oxidative dehydrogenation (ODH) of ethane is an attractive, low energy, alternative route to ethene which could reduce the carbon footprint for its production, however, the commercial implementation of ODH requires catalysts with improved selectivity. This review critically assesses recent developments in catalytic technologies for ethane ODH, and discusses how insight into proposed mechanisms from computational studies, and CO2 assisted ethane dehydrogenation (CO2-DHE), provide opportunities for economically viable processes to meet growing demands for ethene while reducing carbon emissions. Future trends and emerging technologies for ethane ODH are also discussed.

7.
Bioorg Chem ; 110: 104765, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33677248

RESUMO

An approach in modern medicinal chemistry to discover novel bioactive compounds is by mimicking diverse complementary pharmacophores. In extension of this strategy, a new class of piperazine-linked cinnamide derivatives of benzimidazole-pyrimidine hybrids have been designed and synthesized. Their in vitro cytotoxicity profiles were explored on selected human cancer cell lines. Specifically, structural comparison of target hybrids with tubulin-DAMA-colchicine and tubulin-nocodazole complexes has exposed a deep position of benzimidazole ring into the αT5 loop. All the synthesized compounds were demonstrated modest to interesting cytotoxicity against different cancer cell lines. The utmost cytotoxicity has shown with an amine linker of benzimidazole-pyrimidine series, with specificity toward A549 (lung cancer) cell line. The most potent compound in this series was 18i, which inhibited cancer cell growth at micromolar concentrations ranging 2.21-7.29 µM. Flow cytometry studies disclosed that 18i inhibited the cells in G2/M phase of cell cycle. The potent antitumor activity of 18i resulted from enhanced microtubule disruption at a similar level as nocodazole on ß-tubulin antibody, explored using immunofluorescence staining. The most active compound 18i also inhibited tubulin polymerization with an IC50 of 5.72 ± 0.51 µM. In vitro biological analysis of 18i presented apoptosis induction on A549 cells with triggering of ROS generation and loss of mitochondrial membrane potential, resulting in DNA injury. In addition, 18i displayed impairment in cellular migration and inhibited the colony formation. Notably, the safety profile of most potent compound 18i was revealed by screening against normal human pulmonary epithelial cells (L132: IC50: 69.25 ± 5.95 µM). The detailed binding interactions of 18i with tubulin was investigated by employing molecular docking, superimposition and free energy analyses. Thus remarks made in this study established that pyrimidine-benzimidazole hybrids as a new class of tubulin polymerization inhibitors with significant anticancer activity.


Assuntos
Benzimidazóis/química , Benzimidazóis/farmacologia , Cinamatos/química , Pirimidinas/química , Pirimidinas/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Sobrevivência Celular , Desenho de Fármacos , Células HEK293 , Células Hep G2 , Humanos , Modelos Moleculares , Moduladores de Tubulina/química , Moduladores de Tubulina/farmacologia
8.
Inorg Chem ; 59(8): 5662-5673, 2020 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-32255617

RESUMO

A family of stable anticancer gold(III)-based therapeutic complexes containing cyclometalated triphenylphosphine sulfide ligands have been prepared. The anticancer properties of the newly developed complexes [AuCl2{κ2-2-C6H4P(S)Ph2}] (1), [Au(κ2-S2CNEt2){κ2-2-C6H4P(S)Ph2}]PF6 (2), [AuCl(dppe){κC-2-C6H4P(S)Ph2}]Cl (3), and [Au(dppe){κ2-2-C6H4P(S)Ph2}][PF6]2 (4) were investigated toward five human cancer cell lines [cervical (HeLa), lung (A549), prostate (PC3), fibrosarcoma (HT1080), and breast (MDA-MB-231)]. In vitro cytotoxicity studies revealed that compounds 2-4 displayed potent cell growth inhibition (IC50 values in the range of 0.17-2.50 µM), comparable to, or better than, clinically used cisplatin (0.63-6.35 µM). Preliminary mechanistic studies using HeLa cells indicate that the cytotoxic effects of the compounds involve apoptosis induction through ROS accumulation. Compound 2 also demonstrated significant inhibition of endothelial cell migration and tube formation in the angiogenesis process. Evaluation of the in vivo antitumor activity of compound 2 in nude mice bearing cervical cancer cell (HeLa) xenografts indicated significant tumor growth inhibition (55%) with 1 mg/kg dose (every 3 days) compared with the same dose of cisplatin (28%). These results demonstrate the potential of gold(III) complexes containing cyclometalated triphenylphosphine sulfide ligands as novel metal-based anticancer agents.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Complexos de Coordenação/uso terapêutico , Neoplasias/tratamento farmacológico , Fosfinas/uso terapêutico , Sulfetos/uso terapêutico , Inibidores da Angiogênese/síntese química , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Complexos de Coordenação/síntese química , Ensaios de Seleção de Medicamentos Antitumorais , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/uso terapêutico , Feminino , Ouro/química , Humanos , Ligantes , Camundongos Endogâmicos BALB C , Camundongos Nus , Fosfinas/síntese química , Espécies Reativas de Oxigênio/metabolismo , Sulfetos/síntese química , Tiorredoxina Dissulfeto Redutase/antagonistas & inibidores , Ensaios Antitumorais Modelo de Xenoenxerto
9.
J Environ Manage ; 270: 110945, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32721358

RESUMO

Due to the lenient environmental policies in developing economies, mercury-containing wastes are partly produced as a result of the employment of mercury in manufacturing and consumer products. Worldwide, the presence of mercury as an impurity in several industrial processes leads to significant amounts of contaminated waste. The Minamata Convention on Mercury dictates that mercury-containing wastes should be handled in an environmentally sound way according to the Basel Convention Technical Guidelines. Nevertheless, the management policies differ a great deal from one country to another because only a few deploy or can afford to deploy the required technology and facilities. In general, elemental mercury and mercury-bearing wastes should be stabilized and solidified before they are disposed of or permanently stored in specially engineered landfills and facilities, respectively. Prior to physicochemical treatment and depending on mercury's concentration, the contaminated waste may be thermally or chemically processed to reduce mercury's content to an acceptable level. The suitability of the treated waste for final disposal is then assessed by the application of standard leaching tests whose capacity to evaluate its long-term behavior is rather questionable. This review critically discusses the main methods employed for the recovery of mercury and the treatment of contaminated waste by analyzing representative examples from the industry. Furthermore, it gives a complete overview of all relevant issues by presenting the sources of mercury-bearing wastes, explaining the problems associated with the operation of conventional discharging facilities and providing an insight of the disposal policies adopted in selected geographical regions.


Assuntos
Mercúrio , Eliminação de Resíduos , Materiais de Construção , Tecnologia , Instalações de Eliminação de Resíduos
10.
Water Sci Technol ; 82(11): 2259-2270, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33339782

RESUMO

The goal of the present study is to treat industrial wastewater containing sodium aluminate using a chemically inert polyurea (PU) based thin film composite (TFC) reverse osmosis (RO) membrane to promote water reclamation and zero liquid discharge (ZLD). Pretreatment was carried out to reduce the pH of the effluent from 12.5 to 7.1. The TFC RO membrane was fabricated by coating PU on Polyethersulfone (PES) substrate by interfacial polymerization (IP). The surface and cross-sectional morphologies of the membrane were characterized using scanning electron microscopy (SEM). The indigenously synthesized membrane was effective in the removal of total dissolved solids (TDS), chemical oxygen demand (COD), colour and electrical conductivity. The experiments were conducted by varying the feed composition of the wastewater. The maximum water recovery and flux were found to be 74% and 73.9 L/m2·h. RO process using PU membrane exhibited significant potential for cost effective, safe and pollution-free treatment of sodium aluminate industrial effluent.


Assuntos
Águas Residuárias , Purificação da Água , Compostos de Alumínio , Estudos Transversais , Membranas Artificiais , Osmose , Polímeros , Compostos de Sódio
11.
Chemistry ; 25(62): 14089-14100, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31414501

RESUMO

Four cycloaurated phosphine sulfide complexes, [Au{κ2 -2-C6 H4 P(S)Ph2 }2 ][AuX2 ] [X=Cl (2), Br (3), I (4)] and [Au{κ2 -2-C6 H4 P(S)Ph2 }2 ]PF6 (5), have been prepared and thoroughly characterized. The compounds were found to be stable under physiological-like conditions and showed excellent cytotoxicity against a broad range of cancer cell lines and remarkable cytotoxicity in 3D tumor spheroids. Mechanistic studies with cervical cancer (HeLa) cells indicated that the cytotoxic effects of the compounds involve the inhibition of thioredoxin reductase and induction of apoptosis through mitochondrial disruption. In vivo experiments in nude mice bearing HeLa xenografts showed that treatment with compounds 4 and 5 resulted in significant inhibition of tumor growth (35.8 and 46.9 %, respectively), better than that of cisplatin (29 %). The newly synthesized gold complexes were also evaluated for their in vitro and in vivo anti-inflammatory activity through the study of lipopolysaccharide (LPS)-activated macrophages and carrageenan-induced hind paw edema in rats, respectively.


Assuntos
Anti-Inflamatórios/química , Antineoplásicos/química , Ouro/química , Compostos Organoáuricos/química , Fosfinas/química , Sulfetos/química , Animais , Anti-Inflamatórios/farmacologia , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cisplatino/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Compostos Organoáuricos/farmacologia
12.
Langmuir ; 35(25): 8246-8256, 2019 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-31132272

RESUMO

CeO2 nanoparticle-decorated ?-MnO2 nanotubes (NTs) were prepared and tested for elemental mercury (Hg0) vapor removal in simulated natural gas mixtures at ambient conditions. The composition which had the largest surface area and a relative Ce/Mn atomic weight ratio of around 35% exhibited a maximum Hg0 uptake capacity exceeding 20 mg?g?1 (2 wt %), as determined from measurements of mercury breakthrough which corresponded to 99.5% Hg0 removal efficiency over 96 h of exposure. This represents a significant improvement in the activity of pure metal oxides. Most importantly, the composite nanosorbent was repeatedly regenerated at 350 ?C and retained the 0.5% Hg0 breakthrough threshold. It was projected to be able to sustain 20 regeneration cycles, with the presence of acid gases, CO2, and H2S, not affecting its performance. This result is particularly important, considering that pure CeO2 manifests rather poor activity for Hg0 removal at ambient conditions, and hence, a synergistic effect in the composite nanomaterial was observed. This possibly results from the addition of facile oxygen vacancy formation at ?-MnO2 NTs and the increased amount of surface-adsorbed oxygen species.

13.
Chem Rec ; 19(7): 1407-1419, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30536758

RESUMO

The necessity to drastically act against mercury pollution has been emphatically addressed by the United Nations. Coal-fired power plants contribute a great deal to the anthropogenic emissions; therefore, numerous sorbents/catalysts have been developed to remove elemental mercury (Hg0 ) from flue gases. Among them, ceria (CeO2 ) has attracted significant interest, due to its reversible Ce3+ /Ce4+ redox pair, surface-bound defects and acid-base properties. The removal efficiency of Hg0 vapor depends among others, on the flue gas composition and temperature. CeO2 can be incorporated into known materials in such a way that the abatement process can be effective at different operating conditions. Hence, the scope of this account is to discuss the role of CeO2 as a promoter, active phase and support in the design of composite Hg0 sorbents/catalysts. The elucidation of each of these roles would allow the integration of CeO2 advantageous characteristics to such degree, that tailor-made environmental solution to complex issues can be provided within a broader application scope. Besides, it would offer invaluable input to theoretical calculations that could enable the materials screening and engineering at a low cost and with high accuracy.

14.
Photochem Photobiol Sci ; 18(12): 2952-2964, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31657420

RESUMO

Design and synthesis of efficient photocatalyst systems for a large volume of hydrogen (H2) evolution under solar light is still a great challenge. To obtain high photocatalytic activity, graphene-based semiconductor photocatalysts are gaining heightened attention in the field of green and sustainable fuel production due to their good electronic properties, high surface area and chemical stability. Herein, we demonstrate an efficient, novel and smart architecture of a graphene-based ZnIn2S4/g-C3N4 nanojunction by a simple hydrothermal process for H2 generation. In the present study, graphene (G) is chosen as the electron mediator and ZnIn2S4 (ZIS) and g-C3N4 (CN) are chosen as two different semiconductor photocatalysts to construct a smart architecture for the ternary photocatalytic system. Different characterization techniques such as XRD, TGA, FT-IR, SEM, TEM, HR-TEM, XPS, BET, and UV-vis DRS were employed to ensure the successful integration of graphene, ZnIn2S4, and g-C3N4 in the nanocomposite. As a result, high and efficient H2 evolution (477 µmol h-1 g-1) is attained for the graphene-based ZnIn2S4/g-C3N4 nanocomposite. Transient photocurrent experiments, ESR, PL, and time-resolved PL studies suggested that the intimate ternary nanojunction effectively promotes fast charge transfer and thereby enhances photocatalytic H2 evolution.

15.
Inorg Chem ; 58(20): 13999-14004, 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31573192

RESUMO

The rational design of binuclear Au(I)-Au(I), Au(II)-Au(II), and Au(I)-Au(III) complexes requires an understanding of how the redox states interconvert. Herein, the electrochemical interconversion of the three oxidation states I, II, and III is reported on the voltammetric (cyclic and rotating disk electrode) time scales for binuclear gold complexes containing C6F4PPh2 as a ligand, to demonstrate for the first time formation of a binuclear Au(II)-Au(II) from a Au(I)-Au(III) complex. Results are supported by bulk electrolysis and coulometry with reaction products being identified by 31P NMR and UV-vis spectroscopy. All electrochemical processes involve an overall two-electron charge-transfer process with no one-electron intermediate being detected. Importantly, the kinetically rather than thermodynamically favored isomer [Au2IIX2(µ-2-C6F4PPh2)2] is formed on redox cycling of [XAuI(µ-2-C6F4PPh2)(κ2-2-C6F4PPh2)AuIIIX] (X = Cl, ONO2). Finally, a mechanism is proposed to explain the simultaneous change of coordination of the chelating carbanionic ligand to bridging mode and interconversion of oxidation states in binuclear gold complexes.

16.
Bioorg Med Chem ; 27(15): 3285-3298, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31227365

RESUMO

To explore a new set of cytotoxic agents, ß-carboline-combretastatin carboxamide conjugates were designed, synthesized and evaluated for their in vitro cytotoxicity potential, DNA binding affinity and Topoisomerase-II (topo-II) inhibition activity. Among the designed hybrids, 10v and 10af have shown significant cytotoxic effect against A549 (lung cancer) cell line having IC50 value 1.01 µM and 1.17 µM respectively. Further, it was speculated that treatment with compound 10v may induce apoptosis among A549 cells, which was supported by Hoechst staining, DCFDA, Annexin V-FITC and morphological assays. Flow cytometric analysis revealed that the hybrid 10v arrests A549 cells in G2/M phase of cell cycle in a dose dependent manner. Amongst the active hybrids, most potent hybrid 10v was tested for DNA topo-II inhibition activity. Moreover, to further support the biological activity and to infer the mode of interaction between ligands and DNA, spectroscopy and molecular docking studies were carried out. The docking and spectroscopy results showed that the ligands exhibited an intercalative mode of binding with DNA and could efficiently bind to DNA and form topo-II ternary complex. Based on these experiments, the hybrids 10v and 10af were identified as proficient new scaffolds which need to be developed as hit molecules for therapeutic interest.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Bibenzilas/farmacologia , Carbolinas/farmacologia , DNA Topoisomerases Tipo II/metabolismo , DNA de Cinetoplasto/efeitos dos fármacos , Inibidores da Topoisomerase II/farmacologia , Células A549 , Antineoplásicos Fitogênicos/síntese química , Antineoplásicos Fitogênicos/química , Bibenzilas/química , Carbolinas/química , Proliferação de Células/efeitos dos fármacos , DNA de Cinetoplasto/química , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Células HeLa , Humanos , Estrutura Molecular , Relação Estrutura-Atividade , Inibidores da Topoisomerase II/síntese química , Inibidores da Topoisomerase II/química , Células Tumorais Cultivadas
17.
Anal Chem ; 90(8): 5335-5342, 2018 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-29624368

RESUMO

While many microfluidic devices have been developed for sensing and others for actuation, few devices can perform both tasks effectively and simultaneously on the same platform. In piezoelectric sensors and actuators, this is due to the opposing operating requirements for sensing and actuation. Sensing ideally requires narrow resonant peaks characterized by high quality factors, such as those found in quartz crystals. However, these materials usually have poor electromechanical coupling coefficients that are not ideal for actuation. In this work, we show that it is possible to achieve both sensing and actuation simultaneously on a shared device by exploiting the distinct advantages of both bulk waves for effective mass sensing and surface waves for highly efficient microfluidic actuation through a unique hybrid surface and bulk acoustic wave platform. In light of the recent resurgence of interest in portable inhaled insulin devices for personalized diabetes management, we demonstrate the use of this technology for efficient aerosolization of insulin for inhalation without denaturing the protein, while being able to concurrently detect the residual mass of the un-nebulized insulin remaining on the device such that the actual dose delivered to the patient can be determined in real time.

18.
Langmuir ; 34(8): 2663-2673, 2018 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-29397744

RESUMO

This work reports the synthesis of heterostructured copper-ceria and iron-ceria nanorods and the role of their morphology, redox, and acid properties in catalytic diesel soot combustion. Microscopy images show the presence of nanocrystalline CuO (9.5 ± 0.5 nm) and Fe2O3 (7.3 ± 0.5 nm) particles on the surface of CeO2 nanorods (diameter is 8.5 ± 2 nm and length within 16-89 nm). In addition to diffraction peaks of CuO and Fe2O3 nanocrystallites, X-ray diffraction (XRD) studies reveal doping of Cu2+ and Fe3+ ions into the fluorite lattice of CeO2, hence abundant oxygen vacancies in the Cu/CeO2 and Fe/CeO2 nanorods, as evidenced by Raman spectroscopy studies. XRD and Raman spectroscopy studies further show substantial perturbations in Cu/CeO2 rods, resulting in an improved reducibility of bulk cerium oxide and formation of abundant Lewis acid sites, as investigated by H2-temperature-programmed reduction and pyridine-adsorbed Fourier transform infrared studies, respectively. The Cu/CeO2 rods catalyze the soot oxidation reaction at the lowest temperatures under both tight contact (Cu/CeO2; T50 = 358 °C, temperature at which 50% soot conversion is achieved, followed by Fe/CeO2; T50 = 368 °C and CeO2; T50 = 433 °C) and loose contact conditions (Cu/CeO2; T50 = 419 °C and Fe/CeO2; T50 = 435 °C). A possible mechanism based on the synergetic effect of redox and acid properties of Cu/CeO2 nanorods was proposed: acid sites can activate soot particles to form reactive carbon species, which are oxidized by gaseous oxygen/lattice oxygen activated in the oxygen vacancies (redox sites) of ceria rods.

19.
Crit Rev Food Sci Nutr ; 58(9): 1495-1511, 2018 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-28033035

RESUMO

Gelatin is a highly purified animal protein of pig, cow, and fish origins and is extensively used in food, pharmaceuticals, and personal care products. However, the acceptability of gelatin products greatly depends on the animal sources of the gelatin. Porcine and bovine gelatins have attractive features but limited acceptance because of religious prohibitions and potential zoonotic threats, whereas fish gelatin is welcomed in all religions and cultures. Thus, source authentication is a must for gelatin products but it is greatly challenging due to the breakdown of both protein and DNA biomarkers in processed gelatins. Therefore, several methods have been proposed for gelatin identification, but a comprehensive and systematic document that includes all of the techniques does not exist. This up-to-date review addresses this research gap and presents, in an accessible format, the major gelatin source authentication techniques, which are primarily nucleic acid and protein based. Instead of presenting these methods in paragraph form which needs much attention in reading, the major methods are schematically depicted, and their comparative features are tabulated. Future technologies are forecasted, and challenges are outlined. Overall, this review paper has the merit to serve as a reference guide for the production and application of gelatin in academia and industry and will act as a platform for the development of improved methods for gelatin authentication.


Assuntos
Cosméticos/análise , Aditivos Alimentares/análise , Análise de Alimentos/métodos , Gelatina/química , Preparações Farmacêuticas/análise , Animais , Bovinos , Eletroforese , Ensaio de Imunoadsorção Enzimática , Peixes , Tecnologia de Alimentos , Marcadores Genéticos , Reação em Cadeia da Polimerase , Reação em Cadeia da Polimerase em Tempo Real , Especificidade da Espécie , Suínos
20.
Chemistry ; 23(64): 16219-16230, 2017 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-28763123

RESUMO

Mercury pollution threatens the environment and human health across the globe. This neurotoxic substance is encountered in artisanal gold mining, coal combustion, oil and gas refining, waste incineration, chloralkali plant operation, metallurgy, and areas of agriculture in which mercury-rich fungicides are used. Thousands of tonnes of mercury are emitted annually through these activities. With the Minamata Convention on Mercury entering force this year, increasing regulation of mercury pollution is imminent. It is therefore critical to provide inexpensive and scalable mercury sorbents. The research herein addresses this need by introducing low-cost mercury sorbents made solely from sulfur and unsaturated cooking oils. A porous version of the polymer was prepared by simply synthesising the polymer in the presence of a sodium chloride porogen. The resulting material is a rubber that captures liquid mercury metal, mercury vapour, inorganic mercury bound to organic matter, and highly toxic alkylmercury compounds. Mercury removal from air, water and soil was demonstrated. Because sulfur is a by-product of petroleum refining and spent cooking oils from the food industry are suitable starting materials, these mercury-capturing polymers can be synthesised entirely from waste and supplied on multi-kilogram scales. This study is therefore an advance in waste valorisation and environmental chemistry.


Assuntos
Mercúrio/química , Óleos de Plantas/química , Enxofre/química , Adsorção , Poluentes Atmosféricos/química , Varredura Diferencial de Calorimetria , Polímeros/síntese química , Polímeros/química , Reciclagem , Poluentes do Solo/química , Propriedades de Superfície , Termogravimetria , Poluentes Químicos da Água/química
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