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1.
J Oleo Sci ; 73(4): 619-623, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38556295

RESUMO

The distribution of electrolytes near the air/water surface plays an essential role in many processes. While the general distribution is governed by classic Poisson-Boltzmann statistics, the analytical solution is only available for symmetric electrolytes. From the recent studies in the literature, it is evident that surface adsorption is dependent on specific ions as well as the H-bond structure at the surface. Experimental data can capture the macro properties of the surface, such as surface tension and surface potential. Yet, the underpinning mechanisms behind this experimental macro-observation remain unclear. To address the challenge, we developed a framework combining experimental studies and numerical calculations. The model was developed for electrolytes with unequal cationic and anionic charges. The asymmetric model was successfully applied to describe the surface charge of MgCl 2 aqueous solution. The results can be explained by the role of cationic size and charge on the surface layer.


Assuntos
Eletrólitos , Água , Água/química , Eletrólitos/química , Íons , Tensão Superficial , Adsorção
2.
Int J Biol Macromol ; 265(Pt 1): 130751, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38471616

RESUMO

The challenge in front of EDLC device is their low energy density compared to their battery counter parts. In the current study, a green plasticized nanocomposite sodium ion conducting polymer blend electrolytes (PNSPBE) was developed by incorporating plasticized Chitosan (CS) blended with polyvinyl alcohol (PVA), doped with NaBr salt with various concentration of CaTiO3 nanoparticles. The most optimized PNSPBE film was subsequently utilized in an EDLC device to evaluate its effectiveness both as an electrolyte and a separator. Structural and morphological changes were assessed using XRD and SEM techniques. The PNSPBE film demonstrated a peak ionic conductivity of 9.76×10-5 S/cm, as determined through EIS analysis. The dielectric and AC studies provided further confirmation of structural modifications within the sample. Both TNM and LSV analyses affirmed the suitability of the prepared electrolyte for energy device applications, evidenced by its adequate ion transference number and an electrochemical potential window of 2.86 V. Electrochemical properties were assessed via CV and GCD techniques, confirming non-Faradaic ion storage, indicated by the rectangular CV pattern at low scan rates. The parameters associated with the designed EDLC device including specific capacitance, ESR, power density (1950 W/kg) and energy density (12.3 Wh/kg) were determined over 1000 cycles.


Assuntos
Quitosana , Polímeros , Polímeros/química , Quitosana/química , Sódio , Eletrólitos/química , Íons/química
3.
Biosensors (Basel) ; 14(2)2024 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-38392025

RESUMO

Precise DNA quantification and nuclear imaging are pivotal for clinical testing, pathological diagnosis, and drug development. The detection and localization of mitochondrial DNA serve as crucial indicators of cellular health. We introduce a novel conjugated oligoelectrolyte (COE) molecule, COE-S3, featuring a planar backbone composed of three benzene rings and terminal side chains. This unique amphiphilic structure endows COE-S3 with exceptional water solubility, a high quantum yield of 0.79, and a significant fluorescence Stokes shift (λex = 366 nm, λem = 476 nm), alongside a specific fluorescence response to DNA. The fluorescence intensity correlates proportionally with DNA concentration. COE-S3 interacts with double-stranded DNA (dsDNA) through an intercalation binding mode, exhibiting a binding constant (K) of 1.32 × 106 M-1. Its amphiphilic nature and strong DNA affinity facilitate its localization within mitochondria in living cells and nuclei in apoptotic cells. Remarkably, within 30 min of COE-S3 staining, cell vitality can be discerned through real-time nuclear fluorescence imaging of apoptotic cells. COE-S3's high DNA selectivity enables quantitative intracellular DNA analysis, providing insights into cell proliferation, differentiation, and growth. Our findings underscore COE-S3, with its strategically designed, shortened planar backbone, as a promising intercalative probe for DNA quantification and nuclear imaging.


Assuntos
DNA , Eletrólitos , Eletrólitos/química , Imagem Óptica/métodos , Mitocôndrias
4.
Int J Biol Macromol ; 262(Pt 1): 129861, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38307434

RESUMO

Natural polymers as battery components have a number of advantages, including availability, biodegradability, unleakage, stable form, superior process, electrochemical stability, and low cost. In other sides, conductive polymers can improve the electrochemical properties of the battery, such as charge/discharge rates, cycling stability, and overall energy storage capacity. Therefore, the combination of these two materials can provide acceptable features. In this study, polymer electrolytes based on cellulose have been synthesized by solution casting method to prepare a thin polymer film. Then, polypyrrole (PPy) was blended with cellulose in different weight ratios. To prevent electrical conductivity of blends, PPy was used <10 wt%. The electrochemical properties of prepared electrolytes have been investigated by different methods. The results showed that ionic conductivity was increased by addition of PPy to cellulose due to the creation of pores and also due to the high dielectric constant of conductive polymers. All synthesized electrolytes had suitable ionic conductivity (in the range of 10-3 S cm-1), significant charge capacity, stable cyclic performance, excellent electrochemical stability (above 4.8 V), and high cation transfer number (between 0.38 and 0.66 for pure cellulose and the sample containing 10 wt% PPy).


Assuntos
Celulose , Polímeros , Polímeros/química , Celulose/química , Lítio/química , Pirróis/química , Eletrólitos/química , Íons
5.
Environ Pollut ; 346: 123552, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38346633

RESUMO

Elucidation of the aggregation behaviors of gold nanoparticles (AuNPs) in water systems is crucial to understanding their environmental fate and transport as well as human health effects. We investigated the early-stage aggregation kinetics of AuNPs coated by human serum albumin (HSA) protein corona (PC) in NaCl and CaCl2 through time-resolved dynamic light scattering. We found that the aggregation of PC-AuNPs depended on the concerted effects of electrolyte concentration, valence, and HSA concentration. At low HSA concentration (≤0.005 g/L), the aggregation kinetics of PC-AuNPs was similar to that of bare AuNPs due to insignificant HSA adsorption. At intermediate HSA concentrations of 0.025-0.050 g/L, the aggregation of PC-AuNPs was retarded in both electrolytes due to steric repulsive forces imparted by the PCs. Additionally, HSA PCs had a weaker retardation effect on PC-AuNPs aggregation in divalent than in monovalent electrolytes. Quartz crystal microbalance measurements revealed that the presence of Ca2+ promoted additional HSA adsorption on PC-AuNPs likely via -COO-Ca2+ bond, and eventually enhanced the aggregation between PC-AuNPs. High-concentration HSA (>0.5 g/L) resulted in no PC-AuNPs aggregation regardless of electrolyte valence and concentrations. Finally, desorption of HSA barely occurred after adsorption on the gold surface, suggesting that the formation of PC-AuNPs is mostly irreversible.


Assuntos
Nanopartículas Metálicas , Coroa de Proteína , Humanos , Ouro/química , Nanopartículas Metálicas/química , Eletrólitos/química , Albumina Sérica Humana , Cinética
6.
Environ Sci Pollut Res Int ; 31(7): 11321-11333, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38217813

RESUMO

A large amount of open-dumped electrolytic manganese residue (EMR) has posed a severe threat to the ecosystem and public health due to the leaching of ammonia (NH4+) and manganese (Mn). In this study, CaO addition coupled with low-temperature roasting was applied for the treatment of EMR. The effects of roasting temperature, roasting time, CaO-EMR mass ratio and solid-liquid ratio were investigated. The most cost-effective and practically viable condition was explored through response surface methodology. At a CaO: EMR ratio of 1:16.7, after roasting at 187 °C for 60 min, the leaching concentrations of NH4+ and Mn dropped to 10.18 mg/L and 1.05 mg/L, respectively, below their discharge standards. In addition, the magnesium hazard (MH) of EMR, which was often neglected, was studied. After treatment, the MH of the EMR leachate was reduced from 60 to 37. Mechanism analysis reveals that roasting can promote NH4+ to escape as NH3 and convert dihydrate gypsum to hemihydrate gypsum. Mn2+ and Mg2+ were mainly solidified as MnO2 and Mg(OH)2, respectively. This study proposes an efficient and low-cost approach for the treatment of EMR and provides valuable information for its practical application.


Assuntos
Amônia , Manganês , Manganês/química , Amônia/análise , Magnésio , Compostos de Manganês/química , Sulfato de Cálcio , Temperatura , Ecossistema , Óxidos/química , Eletrólitos/química
7.
Cornea ; 43(2): 172-177, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37404128

RESUMO

PURPOSE: Tear fluid (TF) contains a variety of electrolytes that exhibit a strong correlation with its osmotic pressure. These electrolytes are also related to the etiology of diseases on ocular surfaces such as dry eye syndromes and keratopathy. Although positive ions (cations) in TF have been investigated to understand their roles, negative ions (anions) have hardly been studied because applicable analytical methods are restricted to a few kinds. In this study, we established a method to analyze the anions involved in a sufficiently small amount of TF for in situ diagnosis of a single subject. METHODS: Twenty healthy volunteers (10 men and 10 women) were recruited. Anions in their TF were measured on a commercial ion chromatograph (IC-2010, Tosoh, Japan). Tear fluid (5 µL or more) was collected from each subject with a glass capillary, diluted with 300 µL of pure water, and conveyed to the chromatograph. We successfully monitored the concentrations of bromide, nitrate, phosphate, and sulfate anions (Br - , NO 3- , HPO 42- , and SO 42- , respectively) in TF. RESULTS: Br - and SO 42- were universally detected in all samples, whereas NO 3- was found in 35.0% and HPO 42- in 30.0% of them. The mean concentrations (mg/L) of each anion were Br - , 4.69 ± 0.96; NO 3- , 0.80 ± 0.68; HPO 42- , 17.48 ± 7.60; and SO 42- , 3.34 ± 2.54. As for SO 42- , no sex differences or diurnal variations were observed. CONCLUSIONS: We established an efficient protocol to quantitate various inorganic anions involved in a small amount of TF using a commercially available instrument. This is the first step to elucidate the role of anions in TF.


Assuntos
Cromatografia , Água , Masculino , Feminino , Humanos , Ânions/análise , Eletrólitos/química , Nitratos
8.
Environ Sci Pollut Res Int ; 31(7): 10296-10316, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36719584

RESUMO

Ionic liquids (ILs), often known as green designer solvents, have demonstrated immense application potential in numerous scientific and technological domains. ILs possess high boiling point and low volatility that make them suitable environmentally benign candidates for many potential applications. The more important aspect associated with ILs is that their physicochemical properties can be effectively changed for desired applications just by tuning the structure of the cationic and/or anionic part of ILs. Furthermore, these eco-friendly designer materials can function as electrolytes or solvents depending on the application. Owing to the distinctive properties such as low volatility, high thermal and electrochemical stability, and better ionic conductivity, ILs are nowadays immensely used in a variety of energy applications, particularly in the development of green and sustainable energy storage and conversion devices. Suitable ILs are designed for specific purposes to be used as electrolytes and/or solvents for fuel cells, lithium-ion batteries, supercapacitors (SCs), and solar cells. Herein, we have highlighted the utilization of ILs as unique green designer materials in Li-batteries, fuel cells, SCs, and solar cells. This review will enlighten the promising prospects of these unique, environmentally sustainable materials for next-generation green energy conversion and storage devices. Ionic liquids have much to offer in the field of energy sciences regarding fixing some of the world's most serious issues. However, most of the discoveries discussed in this review article are still at the laboratory research scale for further development. This review article will inspire researchers and readers about how ILs can be effectively applied in energy sectors for various applications as mentioned above.


Assuntos
Líquidos Iônicos , Líquidos Iônicos/química , Solventes/química , Eletrólitos/química , Íons , Temperatura de Transição
9.
Faraday Discuss ; 249(0): 408-423, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-37791509

RESUMO

Colloidal crystals have applications in water treatments, including water purification and desalination technologies. It is, therefore, important to understand the interactions between colloids as a function of electrolyte concentration. We study the assembly of DNA-grafted gold nanoparticles immersed in concentrated electrolyte solutions. Increasing the concentration of divalent Ca2+ ions leads to the condensation of nanoparticles into face-centered-cubic (FCC) crystals at low electrolyte concentrations. As the electrolyte concentration increases, the system undergoes a phase change to body-centered-cubic (BCC) crystals. This phase change occurs as the interparticle distance decreases. Molecular dynamics analysis suggests that the interparticle interactions change from strongly repulsive to short-range attractive as the divalent-electrolyte concentration increases. A thermodynamic analysis suggests that increasing the salt concentration leads to significant dehydration of the nanoparticle environment. We conjecture that the intercolloid attractive interactions and dehydrated states favour the BCC structure. Our results gain insight into salting out of colloids such as proteins as the concentration of salt increases in the solution.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Coloides/química , DNA/química , Eletrólitos/química , Ouro/química , Nanopartículas/química , Cálcio/química
10.
J Colloid Interface Sci ; 656: 457-465, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38006868

RESUMO

Ion specific effects on the charging and aggregation features of zein nanoparticles (ZNP) were studied in aqueous suspensions by electrophoretic and time-resolved dynamic light scattering techniques. The influence of mono- and multivalent counterions on the colloidal stability was investigated for positively and negatively charged particles at pH values below and above the isoelectric point, respectively. The sequence of the destabilization power of monovalent salts followed the prediction of the indirect Hofmeister series for positively charged particles, while the direct Hofmeister series for negatively charged ones assumed a hydrophobic character for their surface. The multivalent ions destabilized the oppositely charged ZNPs more effectively and the aggregation process followed the Schulze-Hardy rule. For some multivalent ions, strong adsorption led to charge reversal resulting in restabilization of the suspensions. The experimental critical coagulation concentrations (CCCs) could be well-predicted with the theory developed by Derjaguin, Landau, Verwey and Overbeek indicating that the aggregation processes were mainly driven by electrical double layer repulsion and van der Waals attraction. The ion specific dependence of the CCCs is owing to the modification of the surface charge through ion adsorption at different extents. These results are crucial for drug delivery applications, where inorganic electrolytes are present in ZNP samples.


Assuntos
Nanopartículas , Zeína , Eletrólitos/química , Nanopartículas/química , Cátions/química , Suspensões
11.
Environ Sci Technol ; 58(1): 836-846, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38147509

RESUMO

Ion-exchange membranes (IEMs) are widely used in water, energy, and environmental applications, but transport models to accurately simulate ion permeation are currently lacking. This study presents a theoretical framework to predict ionic conductivity of IEMs by introducing an analytical model for condensed counterion mobility to the Donnan-Manning model. Modeling of condensed counterion mobility is enabled by the novel utilization of a scaling relationship to describe screening lengths in the densely charged IEM matrices, which overcame the obstacle of traditional electrolyte chemistry theories breaking down at very high ionic strength environments. Ionic conductivities of commercial IEMs were experimentally characterized in different electrolyte solutions containing a range of mono-, di-, and trivalent counterions. Because the current Donnan-Manning model neglects the mobility of condensed counterions, it is inadequate for modeling ion transport and significantly underestimated membrane conductivities (by up to ≈5× difference between observed and modeled values). Using the new model to account for condensed counterion mobilities substantially improved the accuracy of predicting IEM conductivities in monovalent counterions (to as small as within 7% of experimental values), without any adjustable parameters. Further adjusting the power law exponent of the screen length scaling relationship yielded reasonable precision for membrane conductivities in multivalent counterions. Analysis reveals that counterions are significantly more mobile in the condensed phase than in the uncondensed phase because electrostatic interactions accelerate condensed counterions but retard uncondensed counterions. Condensed counterions still have lower mobilities than ions in bulk solutions due to impedance from spatial effects. The transport framework presented here can model ion migration a priori with adequate accuracy. The findings provide insights into the underlying phenomena governing ion transport in IEMs to facilitate the rational development of more selective membranes.


Assuntos
Eletrólitos , Eletrólitos/química , Íons/química , Troca Iônica , Impedância Elétrica
12.
Chemosphere ; 350: 141078, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38160944

RESUMO

Polyelectrolyte multilayer (PEM) deposition conditions can favorably or adversely affect the membrane filtration performance of various pollutants. Although pH and ionic strength have been proven to alter the characteristics of PEM, their role in determining the buildup interactions that control filtration efficacy has not yet been conclusively proved. A PEM constructed using electrostatic or non-electrostatic interactions from controlled deposition of a weak polyelectrolyte could retain both charged and uncharged pollutants from water. The fundamental relationship between polyelectrolyte charge density, PEM buildup interaction, and filtration performance was explored using a weak-strong electrolyte pair consisting of branching poly (ethyleneimine) and poly (styrene sulfonate) (PSS) across pH ranges of 4-10 and NaCl concentrations of 0 M-0.5 M. PEI/PSS multilayers at acidic pH were dominated by electrostatic interactions, which favored the selective removal of a charged solute, phosphate over chloride, while at alkaline pH, non-electrostatic interactions dominated, which favored the removal of oxybenzone (OXY), a neutral hydrophobic solute. The key factor determining these interactions was the charge density of PEI, which is controlled by pH and ionic strength of the deposition solutions. These findings indicate that the control of buildup interactions can largely influence the physico-chemical and transport characteristics of PEM membranes.


Assuntos
Poluentes Ambientais , Fosfatos , Polieletrólitos , Eletrólitos/química , Soluções
13.
J Am Chem Soc ; 146(1): 660-667, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38131111

RESUMO

Conjugated oligoelectrolytes (COEs) comprise a class of fluorescent reporters with tunable optical properties and lipid bilayer affinity. These molecules have proven effective in a range of bioimaging applications; however, their use in characterizing specific subcellular structures remains restricted. Such capabilities would broaden COE applications to understand cellular dysfunction, cell communication, and the targets of different pharmaceutical agents. Here, we disclose a novel COE derivative, COE-CN, which enables the visualization of mitochondria, including morphological changes and lysosomal fusion upon treatment with depolarizing agents. COE-CN is characterized by the presence of imidazolium solubilizing groups and an optically active cyanovinyl-linked distyrylbenzene core with intramolecular charge-transfer characteristics. Our current understanding is that the relatively shorter molecular length of COE-CN leads to weaker binding within lipid bilayer membranes, which allows sampling of internal cellular structures and ultimately to different localization relative to elongated COEs. As a means of practical demonstration, COE-CN can be used to diagnose cells with damaged mitochondria via flow cytometry. Coupled with an elongated COE that does not translocate upon depolarization, changes in ratiometric fluorescence intensity can be used to monitor mitochondrial membrane potential disruption, demonstrating the potential for use in diagnostic assays.


Assuntos
Eletrólitos , Bicamadas Lipídicas , Bicamadas Lipídicas/química , Eletrólitos/química , Corantes , Citometria de Fluxo
14.
J Chem Inf Model ; 63(22): 6998-7010, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-37948621

RESUMO

Advanced computational methods are being actively sought to address the challenges associated with the discovery and development of new combinatorial materials, such as formulations. A widely adopted approach involves domain-informed high-throughput screening of individual components that can be combined together to form a formulation. This manages to accelerate the discovery of new compounds for a target application but still leaves the process of identifying the right "formulation" from the shortlisted chemical space largely a laboratory experiment-driven process. We report a deep learning model, the Formulation Graph Convolution Network (F-GCN), that can map the structure-composition relationship of the formulation constituents to the property of liquid formulation as a whole. Multiple GCNs are assembled in parallel that featurize formulation constituents domain-intuitively on the fly. The resulting molecular descriptors are scaled based on the respective constituent's molar percentage in the formulation, followed by integration into a combined formulation descriptor that represents the complete formulation to an external learning architecture. The use case of the proposed formulation learning model is demonstrated for battery electrolytes by training and testing it on two exemplary data sets representing electrolyte formulations vs battery performance: one data set is sourced from the literature about Li/Cu half-cells, while the other is obtained by lab experiments related to lithium-iodide full-cell chemistry. The model is shown to predict performance metrics such as Coulombic efficiency (CE) and specific capacity of new electrolyte formulations with the lowest reported errors. The best-performing F-GCN model uses molecular descriptors derived from molecular graphs (GCNs) that are informed with HOMO-LUMO and electric moment properties of the molecules using a knowledge transfer technique.


Assuntos
Fontes de Energia Elétrica , Eletrólitos , Eletrólitos/química , Íons , Ensaios de Triagem em Larga Escala , Lítio
15.
Environ Sci Pollut Res Int ; 30(48): 105056-105071, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37726634

RESUMO

Electrolytic manganese residue (EMR) is a solid waste that contains a significant amount of soluble manganese and ammonia nitrogen, which can pose risks to human health if improperly disposed of. This study aimed to prepare cementitious materials containing abundant ettringite crystals by mixing EMR with various proportions of granulated blast furnace slag (GBFS) and alkaline activators (CaO, Ca(OH)2, clinker, NaOH). The resulting cementitious material not only utilized a substantial amount of EMR but also exhibited comparable strength to ordinary Portland cement. The optimal ratios were determined through mechanical testing. Additionally, the leaching toxicity of cementitious materials was assessed using ICP-MS (inductively coupled plasma mass spectrometer) tests. The microscopic properties, hydration, and mechanism of heavy metal solidification in the cementitious materials were evaluated using XRD (X-ray diffraction), SEM (scanning electron microscope), EDS (energy-dispersive spectrometer), FTIR (Fourier transform infrared spectroscopy), and TG (thermogravimetric) techniques. The results showed that the optimal ratio for the cementitious materials was 60% EMR, 36% GBFS, and 4% Ca(OH)2. The hardened mortar exhibited compressive strengths of 34.43 MPa, 41.3 MPa, and 50.89 MPa at 3 days, 7 days, and 28 days, respectively, with an EMR utilization rate of 60%. The hydration products of EMR-based cementitious materials were C-(A)-S-H, AFt, and ferromanganese compounds, which contribute to the mechanical strength. The Mn2+ and NH4+-N contents of raw EMR were 1220 and 149 mg/L, respectively. Nonetheless, the leaching of Mn2+ and NH4+-N in the alkali-EMR-GBFS system was significantly below the limits set by the Chinese emission standard GB8978-1996. Within this system, C-(A)-S-H and AFt could physically adsorb and displace heavy metals, Ca6Mn2(SO4)2(SO3)2(OH)12·24H2O could replace Al ions with Mn ions, and ferromanganese compounds Fe2Mn(PO4)2(OH)2·(H2O)8 and MnFe2O4 could chemically precipitate Mn2+.


Assuntos
Manganês , Metais Pesados , Humanos , Manganês/química , Ferro , Eletrólitos/química , Íons
16.
Cells ; 12(16)2023 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-37626862

RESUMO

The low distribution of hydrophobic anticancer drugs in patients is one of the biggest limitations during conventional chemotherapy. SDS-based polyelectrolyte multicore nanocarriers (NCs) prepared according to the layer by layer (LbL) procedure can release paclitaxel (PTX), and selectively kill cancer cells. Our main objective was to verify the antitumor properties of PTX-loaded NCs and to examine whether the drug encapsulated in these NCs retained its cytotoxic properties. The cytotoxicity of the prepared nanosystems was tested on MCF-7 and MDA-MB-231 tumour cells and the non-cancerous HMEC-1 cell line in vitro. Confocal microscopy, spectrophotometry, spectrofluorimetry, flow cytometry, and RT PCR techniques were used to define the typical hallmarks of apoptosis. It was demonstrated that PTX encapsulated in the tested NCs exhibited similar cytotoxicity to the free drug, especially in the triple negative breast cancer model. Moreover, SDS/PLL/PTX and SDS/PLL/PGA/PTX significantly reduced DNA synthesis. In addition, PTX-loaded NCs triggered apoptosis and upregulated the transcription of Bax, AIF, cytochrome-c, and caspase-3 mRNA. Our data demonstrate that these novel polyelectrolyte multicore NCs coated with PLL or PLL/PGA are good candidates for delivering PTX. Our discoveries have prominent implications for the possible choice of newly synthesized, SDS-based polyelectrolyte multicore NCs in different anticancer therapeutic applications.


Assuntos
Neoplasias da Mama , Nanopartículas , Paclitaxel , Dodecilsulfato de Sódio , Paclitaxel/administração & dosagem , Humanos , Linhagem Celular Tumoral , Neoplasias da Mama/tratamento farmacológico , Nanopartículas/administração & dosagem , Nanopartículas/química , Dodecilsulfato de Sódio/administração & dosagem , Eletrólitos/química , Apoptose/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos
17.
Environ Pollut ; 335: 122234, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37482335

RESUMO

Electrolytic manganese residue (EMR) stockpiles contain significant amounts of Mn2+ and NH4+-N which pose a risk of environmental pollution. For EMR safe disposal, an innovative approach is proposed that involves direct sodium silicate-sodium hydroxide (Na2SiO3-NaOH) collaborative technology. This approach utilises Na2SiO3 and NaOH as the solidifying agent and activator, respectively, to treat EMR without hazardous effects. The study also provides insights into the kinetics of Mn2+ leaching under the effect of Na2SiO3-NaOH. Leaching efficiency was determined by varying parameters such as stirring rate, reaction temperature, pH of the initial solution, Na2SiO3 concentration, and reaction time to investigate the efficacy of this method. The study indicates that the co-treatment technology of Na2SiO3-NaOH can achieve maximum solidification efficiencies of 99.7% and 98.2% for Mn2+ and NH4+-N, respectively. The process can successfully solidify Mn2+ by synthesising Mn(OH)2 and MnSiO3 in an alkaline environment under optimal conditions including stirring rate of 450 rpm, initial solution pH of 8, test temperature of 40 °C, test time of 420 min, and Na2SiO3 content of 5%. The findings of this study have confirmed that surface chemistry plays a vital role in regulating the test rate and the proposed equation accurately describes Mn2+ leaching kinetics. Overall, the co-treatment technology involving Na2SiO3-NaOH is a viable solution for EMR resource utilisation without compromising environmental safety. This method has the potential to be implemented for other waste streams with comparable compositions, ultimately promoting the sustainable management of waste.


Assuntos
Eletrólitos , Manganês , Manganês/química , Hidróxido de Sódio , Eletrólitos/química , Íons
18.
Sci Rep ; 13(1): 10934, 2023 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-37414786

RESUMO

Organic radical batteries (ORBs) represent a viable pathway to a more sustainable energy storage technology compared to conventional Li-ion batteries. For further materials and cell development towards competitive energy and power densities, a deeper understanding of electron transport and conductivity in organic radical polymer cathodes is required. Such electron transport is characterised by electron hopping processes, which depend on the presence of closely spaced hopping sites. Using a combination of electrochemical, electron paramagnetic resonance (EPR) spectroscopic, and theoretical molecular dynamics as well as density functional theory modelling techniques, we explored how compositional characteristics of cross-linked poly(2,2,6,6-tetramethyl-1-piperidinyloxy-4-yl methacrylate) (PTMA) polymers govern electron hopping and rationalise their impact on ORB performance. Electrochemistry and EPR spectroscopy not only show a correlation between capacity and the total number of radicals in an ORB using a PTMA cathode, but also indicates that the state-of-health degrades about twice as fast if the amount of radical is reduced by 15%. The presence of up to 3% free monomer radicals did not improve fast charging capabilities. Pulsed EPR indicated that these radicals readily dissolve into the electrolyte but a direct effect on battery degradation could not be shown. However, a qualitative impact cannot be excluded either. The work further illustrates that nitroxide units have a high affinity to the carbon black conductive additive, indicating the possibility of its participation in electron hopping. At the same time, the polymers attempt to adopt a compact conformation to increase radical-radical contact. Hence, a kinetic competition exists, which might gradually be altered towards a thermodynamically more stable configuration by repeated cycling, yet further investigations are required for its characterisation.


Assuntos
Eletrólitos , Polímeros , Transporte de Elétrons , Eletrólitos/química , Radicais Livres/química , Polímeros/química , Eletrônica
19.
Molecules ; 28(13)2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37446761

RESUMO

An ionic liquid (IL) 1-ethyl, 2-methyl imidazolium thiocyanate incorporated biopolymer system is reported in this communication for applications in dual energy devices, i.e., electric double-layer capacitors (EDLCs) and dye-sensitized solar cells (DSSCs). The solution caste method has been used to synthesize ionic-liquid-incorporated biopolymer electrolyte films. The IL mixed biopolymer electrolytes achieve high ionic conductivity up to the order of 10-3 S/cm with good thermal stability above 250 °C. Electrical, structural, and optical studies of these IL-doped biopolymer electrolyte films are presented in detail. The performance of EDLCs was evaluated using low-frequency electrochemical impedance spectroscopy, cyclic voltammetry, and constant current charge-discharge, while that of DSSCs was assessed using J-V characteristics. The EDLC cells exhibited a high specific capacitance of 200 F/gram, while DSSCs delivered 1.53% efficiency under sun conditions.


Assuntos
Líquidos Iônicos , Líquidos Iônicos/química , Corantes/química , Eletrólitos/química , Íons , Biopolímeros
20.
Int J Mol Sci ; 24(13)2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37446124

RESUMO

Hybrid nanocomposite materials Bu4NBF4-MgO were obtained using a nanocrystalline MgO with a specific surface area of 324 m2/g and the grains size of 5.1 nm. As a result of the strong adhesion, the salt transforms into an interface-stabilized amorphous state within the thin layer near the interface. The analysis of the DSC data allowed one to estimate the concentration and the thickness of this amorphous layer as 4.8 nm. The amorphous interface phase has an enhanced ionic conductivity. As a result, conductivity of the nanocomposite increases with the concentration of the amorphous phase and reaches 1.1 × 10-3 S/cm at 150 °C at a concentration of the MgO additive x = 0.90 corresponding to the maximum content of the amorphous phase. The conductivity of the nanocomposite is by three orders of magnitude higher than the conductivity of pure Bu4NBF4. The nanocomposites are electrochemically stable up to 2.5 V. At high concentrations of MgO when the total volume of the salt is small the composites become nano- and mesoporous.


Assuntos
Óxido de Magnésio , Nanocompostos , Óxido de Magnésio/química , Nanocompostos/química , Eletrólitos/química , Íons
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