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1.
ACS Appl Mater Interfaces ; 15(31): 37454-37466, 2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37506322

RESUMO

Lithium-ion capacitors (LIC) combine the energy storage mechanisms of lithium-ion batteries and electric double layer capacitors (EDLC) and are supposed to promise the best of both worlds: high energy and power density combined with a long life. However, the lack of lithium cation sources in the carbon cathode demands the cumbersome step of prelithiation of the graphite anode, mainly by using sacrificial lithium metal, hindering the mass adoption of LICs. Here, in a conceptually new class of devices termed lithium metal capacitors (LMC), we replace the graphite anode with a lithium metal anode stabilized by a complex yet stable solid-electrolyte interface (SEI). Via a specialized formation process, the well-explored synergetic reaction between the LiNO3 additive and controlled amounts of polysulfides in an ether-based electrolyte stabilizes the SEI on the lithium metal electrode. Optimized devices at the coin cell level deliver 55 mAh g-1 at a fast 30C discharge rate and maintain 95% capacity after 8000 cycles. At the pouch-cell level, energy densities of 13 Wh kg-1 are readily achieved, indicating the transferability of the technology to practical scales. The LMC, a new class of capacitive device, eliminates the prelithiation process of the conventional LIC, allowing practical production at scale and offering exciting avenues for exploring versatile cathode chemistries on account of using a lithium metal anode.

2.
ChemSusChem ; 15(19): e202201136, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-35843909

RESUMO

Per- and polyfluoroalkyl substances (PFAS) are a group of recalcitrant molecules that have been used since the 1940s in a variety of applications. They are now linked to a host of negative health outcomes and are extremely resistant to degradation under environmental conditions. Currently, membrane technologies or adsorbents are used to remediate contaminated water. These techniques are either inefficient at capturing smaller PFAS molecules, have high energy demands, or result in concentrated waste that must be incinerated at high temperatures. This Review focuses on what role metal-organic frameworks (MOFs) may play in addressing the PFAS problem. Specifically, how the unique properties of MOFs such as their well-defined pore sizes, ultra-high internal surface area, and tunable surface chemistry may be a sustainable solution for PFAS contamination.


Assuntos
Fluorocarbonos , Estruturas Metalorgânicas , Água
3.
Acta Biomater ; 142: 320-331, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35134566

RESUMO

The invaluable health, economic and social impacts of vaccination are hard to exaggerate. The ability to stabilize vaccines is urgently required for their equitable distribution without the dependence on the 'cold-chain' logistics. Herein, for the first time we report biomimetic-mineralization of live-viral vaccines using metal-organic frameworks (MOFs) to enhance their storage stability from days to months. Applying ZIF-8 and aluminium fumarate (Alfum), the Newcastle Disease Virus (NDV) V4 strain and Influenza A WSN strain were encapsulated with remarkable retention of their viral titre. The ZIF-8@NDV, ZIF-8@WSN and Alfum@WSN composites were validated for live-virus recovery using a tissue culture infectious dose (TCID50) assay. With the objective of long-term stabilization, we developed a novel, trehalose (T) and skim milk (SM) stabilized, freeze-dried MOF@Vaccine composite, ZIF-8@NDV+T/SM. The thermal stability of this composite was investigated and compared with the control NDV and non-encapsulated, freeze-dried NDV+T/SM composite at 4 °C, RT, and 37 °C over a period of 12 weeks. We demonstrate the fragility of the control NDV vaccine which lost all viability at RT and 37°C by 12 and 4 weeks, respectively. Comparing the freeze-dried counterparts, the MOF encapsulated ZIF-8@NDV+T/SM demonstrated significant enhancement in stability of the NDV+T/SM composite especially at RT and 37 °C upto 12 weeks. STATEMENT OF SIGNIFICANCE: Vaccination is undoubtedly one of the most effective medical interventions, saving millions of lives each year. However, the requirement of 'cold-chain' logistics is a major impediment to widespread immunization. Live viral vaccines (LVVs) are widely used vaccine types with proven efficacy and low cost. Nonetheless, their complex composition increases their susceptability to thermal stress. Several LVV thermostabilization approaches have been investigated, including their complex engineering and the facile addition of stabilizers. Still, the lack of a universal approach urgently requires finding a stabilization technique especially when additives alone may not be sufficient. Herein, we demonstrate MOF biomimetic-mineralization technology to encapsulate LVVs developing an optimised composite which significantly preserves vaccines without refrigeration for extended periods of time.


Assuntos
Estruturas Metalorgânicas , Doença de Newcastle , Vacinas Virais , Animais , Biomimética , Galinhas , Estruturas Metalorgânicas/farmacologia , Doença de Newcastle/prevenção & controle , Vírus da Doença de Newcastle , Vacinas Atenuadas
4.
Sci Adv ; 6(1): eaay2757, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31922008

RESUMO

Lithium-sulfur batteries can displace lithium-ion by delivering higher specific energy. Presently, however, the superior energy performance fades rapidly when the sulfur electrode is loaded to the required levels-5 to 10 mg cm-2- due to substantial volume change of lithiation/delithiation and the resultant stresses. Inspired by the classical approaches in particle agglomeration theories, we found an approach that places minimum amounts of a high-modulus binder between neighboring particles, leaving increased space for material expansion and ion diffusion. These expansion-tolerant electrodes with loadings up to 15 mg cm-2 yield high gravimetric (>1200 mA·hour g-1) and areal (19 mA·hour cm-2) capacities. The cells are stable for more than 200 cycles, unprecedented in such thick cathodes, with Coulombic efficiency above 99%.

5.
Langmuir ; 34(50): 15343-15349, 2018 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-30441895

RESUMO

The role of nanoparticles in cancer medicine is vast with debate still surrounding the distinction between therapeutic efficacy of actively targeted nanoparticles versus passively targeted systems for drug delivery. While it is commonly accepted that methodologies that result in homing a high concentration of drug loaded nanoparticles to the tumor is beneficial, the role of intracellular trafficking of these nanoparticles in dictating the overall therapeutic outcome remains unresolved. Herein we demonstrate that the therapeutic outcome of drug loaded nanoparticles is governed beyond simply enabling nanoparticle internalization in cells. Using two model polymeric nanoparticles, one decorated with the GE11 peptide for active targeting of the epidermal growth factor receptor (EGFR) and the other without, we demonstrate that EGFR mediated intracellular internalization results in an enhanced therapeutic effect compared to the nontargeted formulation. Our findings demonstrate that the intracellular destination of nanoparticles beyond its ability to internalize is an important parameter that has to be accounted for in the design of targeted drug delivery systems.


Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Docetaxel/farmacologia , Nanopartículas/química , Antineoplásicos/química , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Docetaxel/química , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Ensaios de Seleção de Medicamentos Antitumorais , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/metabolismo , Feminino , Humanos , Células MCF-7 , Nanopartículas/metabolismo , Tamanho da Partícula , Peptídeos/química , Peptídeos/metabolismo , Polímeros/química , Polímeros/metabolismo , Propriedades de Superfície
6.
ACS Appl Mater Interfaces ; 8(7): 4934-9, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26780245

RESUMO

Synthetic multifunctional electrospun composites are a new class of hybrid materials with many potential applications. However, the lack of an efficient, reactive large-area substrate has been one of the major limitations in the development of these materials as advanced functional platforms. Herein, we demonstrate the utility of electrospun poly(glycidyl methacrylate) films as a highly versatile platform for the development of functional nanostructured materials anchored to a surface. The utility of this platform as a reactive substrate is demonstrated by grafting poly(N-isopropylacrylamide) to incorporate stimuli-responsive properties. Additionally, we demonstrate that functional nanocomposites can be fabricated using this platform with properties for sensing, fluorescence imaging, and magneto-responsiveness.

7.
Small ; 12(3): 351-9, 2016 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-26619362

RESUMO

The paradigm of using nanoparticle-based formulations for drug delivery relies on their enhanced passive accumulation in the tumor interstitium. Nanoparticles with active targeting capabilities attempt to further enhance specific delivery of drugs to the tumors via interaction with overexpressed cellular receptors. Consequently, it is widely accepted that drug delivery using actively targeted nanoparticles maximizes the therapeutic benefit and minimizes the off-target effects. However, the process of nanoparticle mediated active targeting initially relies on their passive accumulation in tumors. In this article, it is demonstrated that these two tumor-targeted drug delivery mechanisms are interrelated and dosage dependent. It is reported that at lower doses, actively targeted nanoparticles have distinctly higher efficacy in tumor inhibition than their passively targeted counterparts. However, the enhanced permeability and retention effect of the tumor tissue becomes the dominant factor influencing the efficacy of both passively and actively targeted nanoparticles when they are administered at higher doses. Importantly, it is demonstrated that dosage is a pivotal parameter that needs to be taken into account in the assessment of nanoparticle mediated targeted drug delivery.


Assuntos
Nanopartículas/química , Ácidos Polimetacrílicos/química , Taxoides/farmacologia , Transferrina/química , Animais , Linhagem Celular Tumoral , Docetaxel , Relação Dose-Resposta a Droga , Endocitose , Humanos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Camundongos Nus , Nanopartículas/ultraestrutura , Baço/efeitos dos fármacos , Baço/metabolismo , Taxoides/uso terapêutico
8.
ACS Omega ; 1(6): 1114-1120, 2016 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-30023503

RESUMO

Colloidal poly(glycidyl methacrylate) nanoparticles (NPs) are demonstrated to be platforms facilitating the "click" chemistry approach of surface functionalization for receptor targeting. Folate receptor-targeted NPs were synthesized, physicochemically characterized, confirmed for their biocompatibility, and validated for their selective targeting capabilities for ovarian cancer cells in vitro.

9.
ACS Nano ; 9(1): 279-89, 2015 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-25493575

RESUMO

Increased reactive oxygen species (ROS) production and elevated intracellular Ca(2+) following cardiac ischemia-reperfusion injury are key mediators of cell death and the development of cardiac hypertrophy. The L-type Ca(2+) channel is the main route for calcium influx in cardiac myocytes. Activation of the L-type Ca(2+) channel leads to a further increase in mitochondrial ROS production and metabolism. We have previously shown that the application of a peptide derived against the alpha-interacting domain of the L-type Ca(2+) channel (AID) decreases myocardial injury post reperfusion. Herein, we examine the efficacy of simultaneous delivery of the AID peptide in combination with the potent antioxidants curcumin or resveratrol using multifunctional poly(glycidyl methacrylate) (PGMA) nanoparticles. We highlight that drug loading and dissolution are important parameters that have to be taken into account when designing novel combinatorial therapies following cardiac ischemia-reperfusion injury. In the case of resveratrol low loading capacity and fast release rates hinder its applicability as an effective candidate for simultaneous therapy. However, in the case of curcumin, high loading capacity and sustained release rates enable its effective simultaneous delivery in combination with the AID peptide. Simultaneous delivery of the AID peptide with curcumin allowed for effective attenuation of the L-type Ca(2+) channel-activated increases in superoxide (assessed as changes in DHE fluorescence; Empty NP = 53.1 ± 7.6%; NP-C-AID = 7.32 ± 3.57%) and mitochondrial membrane potential (assessed as changes in JC-1 fluorescence; Empty NP = 19.8 ± 2.8%; NP-C-AID=13.05 ± 1.78%). We demonstrate in isolated rat hearts exposed to ischemia followed by reperfusion, that curcumin and the AID peptide in combination effectively reduce muscle damage, decrease oxidative stress and superoxide production in cardiac myocytes.


Assuntos
Antioxidantes/química , Antioxidantes/farmacologia , Canais de Cálcio Tipo L/química , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Nanopartículas/química , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/farmacologia , Animais , Curcumina/química , Curcumina/farmacologia , Portadores de Fármacos/química , Interações Medicamentosas , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Miócitos Cardíacos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Polietilenoimina/química , Ácidos Polimetacrílicos/química , Ratos , Resveratrol , Estilbenos/química , Estilbenos/farmacologia , Superóxidos/metabolismo
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