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1.
J Cell Mol Med ; 28(8): e18272, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38568057

RESUMO

The pathophysiological foundations of various diseases are often subject to alteration through the utilization of small compounds, rendering them invaluable tools for the exploration and advancement of novel therapeutic strategies. Within the scope of this study, we meticulously curated a diverse library of novel small compounds meticulously designed to specifically target the c-Myc/Max complex. We conducted in vitro examinations of novel c-Myc inhibitors across a spectrum of cancer cell lines, including PANC1 (pancreatic adenocarcinoma), MCF7 (breast carcinoma), DU-145 (prostate carcinoma), and A549 (lung cancer). The initial analysis involved a 25 µM dose, which enabled the identification of potent anticancer compounds effective against a variety of tumour types. We identified c-Myc inhibitors with remarkable potency, featuring IC50 values as low as 1.6 µM and up to 40 times more effective than the reference molecule in diminishing cancer cell viability. Notably, c-Myc-i7 exhibited exceptional selectivity, displaying 37-fold and 59-fold preference for targeting prostate and breast cancers, respectively, over healthy cells. Additionally, we constructed drug-likeness models. This study underscores the potential for in vitro investigations of various tumour types using novel c-Myc inhibitors to yield ground-breaking and efficacious anticancer compounds.


Assuntos
Adenocarcinoma , Neoplasias Pancreáticas , Masculino , Humanos , Linhagem Celular , Núcleo Celular , Sobrevivência Celular
2.
Small ; : e2400675, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39150058

RESUMO

Poor dispersibility of carbon nanotubes greatly hinders their practical applications. Herein, a long-term stable dispersion of multiwalled carbon nanotubes (MWCNTs) in peroxydisulfate (PDS) is achieved. MWCNTs at 40 mg L-1 are completely dispersed by PDS upon ultrasonication (US/PDS) within 64 min and a stable dispersion is maintained at least 20 days. Mechanistically, US created defects on the nanomaterial and PDS-origin free radicals attacked these defects to introduce O-containing moieties (─OH and ─COOH). Interestingly, dispersion efficiency of MWCNTs by US/PDS initially at pH 7 and 3.8 is comparable, but lower than that initially at pH 12. Both •OH and SO4 •- are produced under alkaline condition, while SO4 •- is the dominant free radicals initially at pH 7 and 3.8 during the whole dispersion period. Stronger dispersion of MWCNTs initially at pH 12 resulted from greater amounts of O-containing moieties mainly in ─OH (46.32%) rather than ─COOH (24.19%) form. This differential more strongly promotes MWCNTs-water interaction via hydrogen bonding, thereby enhancing the dispersion. Notably, no significant mass loss of MWCNTs occurred during dispersion. Overall, the developed method achieves long-term stable dispersion of MWCNTs in a manner that can significantly extend their applications.

3.
Chemistry ; : e202402403, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39198977

RESUMO

Bromine (Br2) and related species removal from water systems are rather complicated due to the complicated chemistry instability, and materials with high Br2 removal rate and efficiency, along with stimuli/apparatus suitable for highly corrosive environments, are necessary. Ultrasonication as a non-destructive process is especially suitable in scenarios where conventional stir apparatus is not applicable, such as highly corrosive environments. Considering the validity nature of Br2 and combining the advantages of ultrasonic with a highly stable Br2 fixation method through aromatic polymer nanoparticles, we demonstrate highly efficient acoustic-aided Br2 removal in aqueous solutions with two times capacity compared to the non-treated sample. Related aquatic applications are also proposed for the materials to be cost-effective, including silver (Ag) recovery, recyclable MnO2-mediated Br2 deep removal, and aqueous zinc anode modification. The coupled novel-material-based processes motivate the strategic design of water purification with high-safety and sustainable industrial procedures and post-value-added utilizations.

4.
Mar Drugs ; 22(4)2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38667796

RESUMO

Palmaria palmata is a viable source of nutrients with bioactive properties. The present study determined the potential role of post-extraction ultrasonication on some compositional features and antioxidant properties of enzymatic/alkaline extracts of P. palmata (EAEP). No significant difference was detected in terms of protein content and recovery, as well as the amino acid composition of the extracts. The nitrogen-to-protein conversion factor of 5 was found to be too high for the seaweed and EAEP. The extracts sonicated by bath for 10 min and not sonicated showed the highest and lowest total phenolic contents (p < 0.05), respectively. The highest radical scavenging and lowest metal-chelating activities were observed for the non-sonicated sample, as evidenced by IC50 values. The extract sonicated by bath for 10 min showed the most favorable in vitro antioxidant properties since its radical scavenging was not significantly different from that of the not-sonicated sample (p > 0.05). In contrast, its metal-chelating activity was significantly higher (p < 0.05). To conclude, post-extraction ultrasonication by an ultrasonic bath for 10 min is recommended to increase phenolic content and improve the antioxidant properties of EAEP.


Assuntos
Antioxidantes , Quelantes , Fenóis , Extratos Vegetais , Rodófitas , Antioxidantes/química , Antioxidantes/isolamento & purificação , Quelantes/química , Algas Comestíveis/química , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/isolamento & purificação , Fenóis/química , Fenóis/isolamento & purificação , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Rodófitas/química , Sonicação
5.
Mikrochim Acta ; 191(10): 576, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39240389

RESUMO

Hydroquinone-based organic molecules are often used as unavoidable preservatives in the food industry. Among these additives, tertiary butylated hydroquinone (TBHQ) is widely employed as a preservative in various processed foods. However, the potential health risks associated with the excessive presence of TBHQ in food products have raised significant concerns. To address this pressing issuea novel binder-free composite composed of a manganese metal-organic framework and functionalized carbon nanofibers (Mn-MOF/f-CNF) has been developed as an electrode modifier for the ultrasensitive detection of TBHQ in food samples. The Mn-MOF/f-CNF composite was achieved using the ultrasonication method, revealing a lamellar sheet-like structure of the Mn-MOF and the curly thread-like fibrous structure of f-CNF. The developed Mn-MOF/f-CNF/SPE sensor system resulted in well-defined redox signals for TBHQ detection in a neutral pH solution. Compared to the unmodified SPE system, the modified system showed approximately a 300 mV reduction in overpotential and a twofold increase in peak current signal for TBHQ detection. The Mn-MOF/f-CNF/SPE sensor system showed a linear concentration window of 0.01 to 800 µM with a sensitivity of 6.28 µA µM-1 cm-2 and the obtained detection limit was 1.36 nM. Additionally, the proposed sensor displayed excellent reproducibility and repeatable results with an RSD of less than 5%. The real-time applicability of the Mn-MOF/f-CNF/SPE sensor system was demonstrated using real samples such as potato chips and instant noodles, showing excellent results with a recovery range of 95.1-98.5%.


Assuntos
Técnicas Eletroquímicas , Eletrodos , Hidroquinonas , Limite de Detecção , Manganês , Estruturas Metalorgânicas , Hidroquinonas/química , Hidroquinonas/análise , Estruturas Metalorgânicas/química , Técnicas Eletroquímicas/métodos , Técnicas Eletroquímicas/instrumentação , Manganês/química , Contaminação de Alimentos/análise , Análise de Alimentos/métodos , Conservantes de Alimentos/análise , Conservantes de Alimentos/química
6.
J Sci Food Agric ; 104(4): 2326-2335, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-37953475

RESUMO

BACKGROUND: The development of a safe and effective iron supplement is important for the treatment of iron-deficient anemia. Therefore, the crude hemeprotein extract (CHPE) from Asian seabass gills was extracted without (CON) and with ultrasound (US)-assisted process, followed by freeze-drying. The resulting freeze-dried crude hemeprotein extract (FDCHPE) powders were determined for trace mineral content, color, secondary structure, protein pattern, size distribution, volatile compounds, and amino acid composition. RESULTS: The extraction yields of CON-FDCHPE and US-FDCHPE were 6.76% and 13.65%, respectively. Highest heme iron (0.485 mg/mL) and non-heme iron (0.023 mg/mL) contents were found when US at 70% amplitude for 10 min (US 70/10) was applied. Both CON-FDCHPE and US-FDCHPE had no heavy metals, but higher iron content (432.8 mg/kg) was found in US-FDCHPE (P < 0.05). Typical red color was observed in CON-FDCHPE and US-FDCHPE with a*-values of 9.72 and 10.60, respectively. Ultrasonication affected protein structure, in which ß-sheet upsurged, whereas random coil, α-helix, and ß-turn were reduced. Protein pattern confirmed that both samples had myoglobin as the major protein. US-FDCHPE also showed a higher abundance of volatile compounds, especially propanal, hexanal, heptanal, and so forth, compared to CON-FDCHPE. Amino acid composition of US-FDCHPE was comparable to Food and Agriculture Organization of the United Nations (FAO) values. CONCLUSION: Overall, FDCHPE extracted using ultrasonication could be safe and effective for fortification in food products as an iron supplement to alleviate iron-deficient anemia. Additionally, gills as leftovers could be better exploited rather than being disposed. © 2023 Society of Chemical Industry.


Assuntos
Anemia , Brânquias , Animais , Brânquias/metabolismo , Ferro/metabolismo , Mioglobina , Aminoácidos
7.
Water Sci Technol ; 89(10): 2593-2604, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38822602

RESUMO

The number of published literature on the effect of ultrasonic cavitation and advanced oxidation pretreatment on the dewatering performance of anaerobically digested sludge is very limited. This study aims at determining the optimum operating conditions of large-scale filtering centrifuges in wastewater treatment plants. The optimum dose of hydrogen peroxide, ultrasonic power, ultrasonic duration, ultrasonic pulse and particle size distribution for improved dewatering performance were determined in this study. In addition, shear stress-shear rate and viscosity-shear rate rheograms were developed to show the rheological flow properties for varying ultrasonic power and treatment duration. Optimum sonication power, time, pulse and amplitude were determined to be 14 W, 1 min, 55/5 and 20%, respectively. At a pH of 6.8, the optimum concentration of hydrogen peroxide was found to be 43.5 g/L. The optimum hydrogen peroxide dose in the combined conditioning experiments was determined to be 500 mg/L at a pH of 3. Under these optimum conditions, capillary suction time was reduced significantly by 71.1%. This study helps to reduce polymer consumption and provides the optimum pretreatment and dewatering operating conditions, and better monitoring and control in the dewatering unit has significant impact in the overall economy of wastewater treatment plants.


Assuntos
Peróxido de Hidrogênio , Oxirredução , Esgotos , Eliminação de Resíduos Líquidos , Esgotos/química , Peróxido de Hidrogênio/química , Eliminação de Resíduos Líquidos/métodos , Ultrassom/métodos , Concentração de Íons de Hidrogênio
8.
Saudi Pharm J ; 32(6): 102096, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38757071

RESUMO

The aim of the current study was to explore the potential of human plasma-derived exosomes as versatile carriers for drug delivery by employing various active and passive loading methods. Exosomes were isolated from human plasma using differential centrifugation and ultrafiltration method. Drug loading was achieved by employing sonication and freeze thaw methods, facilitating effective drug encapsulation within exosomes for delivery. Each approach was examined for its effectiveness, loading efficiency and ability to preserve membrane stability. Methotrexate (MTX), a weak acid model drug was loaded at a concentration of 2.2 µM to exosomes underwent characterization using various techniques such as particle size analysis, transmission electron microscopy and drug loading capacity. Human plasma derived exosomes showed a mean size of 162.15 ± 28.21 nm and zeta potential of -30.6 ± 0.71 mV. These exosomes were successfully loaded with MTX demonstrated a better drug encapsulation of 64.538 ± 1.54 % by freeze thaw method in comparison 55.515 ± 1.907 % by sonication. In-vitro drug release displayed 60 % loaded drug released within 72 h by freeze thaw method that was significantly different from that by sonication method i.e., 99 % within 72 h (p value 0.0045). Moreover, cell viability of exosomes loaded by freeze thaw method was significantly higher than that by sonication method (p value 0.0091) suggested that there was membrane disruption by sonication method. In conclusion, this study offers valuable insights into the potential of human plasma-derived exosomes loaded by freeze thaw method suggest as a promising carrier for improved drug loading and maintenance of exosomal membrane integrity.

9.
J Environ Sci (China) ; 146: 15-27, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38969444

RESUMO

A large amount of sludge is inevitably produced during sewage treatment. Ultrasonication (US) as anaerobic digestion (AD) pretreatment was implemented on different sludges and its effects on batch and semi-continuous AD performance were investigated. US was effective in sludge SCOD increase, size decrease, and CH4 production in the subsequent AD, and these effects were enhanced with an elevated specific energy input. As indicated by semi-continuous AD experiments, the mean daily CH4 production of US-pretreated A2O-, A2O-MBR-, and AO-AO-sludge were 176.9, 119.8, and 141.7 NmL/g-VSadded, which were 35.1%, 32.1% and 78.2% higher than methane production of their respective raw sludge. The US of A2O-sludge achieved preferable US effects and CH4 production due to its high organic content and weak sludge structure stability. In response to US-pretreated sludge, a more diverse microbial community was observed in AD. The US-AD system showed negative net energy; however, it exhibited other positive effects, e.g., lower required sludge retention time and less residual total solids for disposal. US is a feasible option prior to AD to improve anaerobic bioconversion and CH4 yield although further studies are necessary to advance it in practice.


Assuntos
Reatores Biológicos , Metano , Esgotos , Eliminação de Resíduos Líquidos , Metano/metabolismo , Metano/análise , Anaerobiose , Eliminação de Resíduos Líquidos/métodos , Sonicação
10.
Angew Chem Int Ed Engl ; 63(15): e202401097, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38308505

RESUMO

It is highly challenging to reproducibly prepare semiconducting polymers with targeted molecular weight tailored for next-generation photovoltaic applications. Once such an easily accessible methodology is established, which can not only contribute to overcome the current limitation of the statistically determined nature of semiconducting polymers, but also facilitate rapid incorporation into the broad synthetic chemists' toolbox. Here, we describe a simple yet robust ultrasonication-assisted Stille polymerization for accessing semiconducting polymers with high-precision tailored molecular weights (from low to ultrahigh molecular weight ranges) while mitigating their interbatch variations. We propose that ultrasound-induced simultaneous physical and chemical events enable precise control of the semiconducting polymers' molecular weights with high reproducibility to satisfy all the optical/electrical and morphological demands of diverse types of high-performance semiconducting polymer-based devices; as demonstrated in in-depth experimental screenings in applications of both organic and perovskite photovoltaics. We believe that this methodology provides a fast development of new and existing semiconducting polymers with the highest-level performances possible on various photovoltaic devices.

11.
Crit Rev Biotechnol ; : 1-21, 2023 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-37455422

RESUMO

Lignin is a complex of organic polymers that are abundantly present in the plant cell wall which considered of emerging substrates for various kinds of value-added industrial products. Lignin has potential use for the production of green nanomaterials, which exhibit improved or different properties corresponding to their parent polymers. Nano lignin has received significant interest in recent years due to its applications in numerous fields. Lignin, the abundant and limited functionality has challenges for its potential uses. Creating advanced functional lignin-derived material like lignin nanoparticles (LNPs) which significantly alter the biological process has great potential for its applications. In the fields of biotechnology, several lignin extraction processes from various raw materials and diverse synthesis techniques, including acid precipitation, dialysis, solvent shifting/solvent exchange, antisolvent precipitation, homogenization, water-in-oil (W/O) microemulsion, ultra-sonication, interfacial crosslinking, polymerization, and biological pathway can be employed to produce LNPs. The scientific community has recently become more concerned about the transformation of lignin to lignin nanomaterials, including nanoparticles, nanocapsules, nanofibers, nanotubes, and nanofilms. Recent research has shown that lignin nanoparticles (LNPs) are: non-toxic at adequate amounts (both in vitro and in vivo), are economical, and can be biodegradable by bacteria and fungi. In promising studies, LNPs have been investigated for their potential applications in gene delivery systems, drug carriers, biocatalysts, tissue engineering, heavy metal absorbers, encapsulation of molecules, supercapacitors, hybrid nanocomposites, and other applications. This current review addresses the recent advances in the synthesis of LNPs, their advanced application in different areas, future perspectives, and challenges associated with lignin-based nanomaterials.

12.
Crit Rev Food Sci Nutr ; 63(21): 5044-5062, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-34872394

RESUMO

Biopolymeric films manufactured from materials such as starch, cellulose, protein, chitosan, gelatin, and polyvinyl alcohol are widely applied due to their complete biodegradability. While biopolymer-based films exhibit good gas barriers and optical properties when used in packaging, poor moisture resistance and mechanical properties limit their further application. Ultrasonication is a promising, effective technology for resolving these shortcomings, with its high efficiency, environmentally friendly nature, and safety. This review briefly introduces basic ultrasonication principles and their main effects on mechanical properties, transparency, color, microstructure, water vapor permeability, and oxygen resistance. We also describe the thermal performance of biopolymeric films. While ultrasonication has many positive effects on the physicochemical properties of biopolymeric films, many factors influence their behavior during film preparation, including power density, amplitude, treatment time, frequency, and the inherent properties of the source materials. This review focuses on biopolymers as film-forming materials and comprehensively discusses the promotional effects of ultrasonication on their physicochemical properties.


Assuntos
Celulose , Amido , Celulose/química , Permeabilidade , Amido/química , Embalagem de Alimentos
13.
Crit Rev Food Sci Nutr ; : 1-20, 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37880974

RESUMO

Shrimps are a widely cultivated species among crustaceans worldwide due to their nutritional profile and delicacy. Because of their unique flavor, shrimp-based food products are gaining consumer demand, so there is a need to understand the flavor chemistry of shrimp meat. Further, the processing and macromolecules of shrimp meat play a significant role in flavor generation and suggest a focus on their research. However, shrimp processing generates a large amount of solid and liquid waste, creating disposal problems and environmental hazards. To overcome this, utilizing these waste products, a rich source of valuable flavor compounds is necessary. This review comprehensively discusses the nutritional aspects, flavor profile, and role of macromolecules in the flavor generation of shrimp meat. Besides, recent trends in analyzing the aroma profile of shrimp and the benefits of shrimp by-products as a source of flavor compounds have been addressed. The delicious flavor of shrimp meat is due to its volatile and nonvolatile flavor compounds. Proteins play a major role in the textural and flavor adsorption properties of shrimp meat-based products. Green extraction technologies, especially ultrasonication, are recommended for valorizing shrimp by-products as a source of flavor compounds, which have enormous applications in the food and flavor industries.

14.
Environ Sci Technol ; 57(16): 6425-6434, 2023 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-37036754

RESUMO

The potential risk of various silver-containing nanoparticles (AgCNPs) in soils is related to the concentration, size, and speciation, but their determination remains a great challenge. Herein, we developed an effective method for determining the particle number, size, and species of dominant AgCNPs in soils, including nanoparticles of silver (Ag NPs), silver chloride (AgCl NPs), and silver sulfide (Ag2S NPs). By ultrasonication wand-assisted tetrasodium pyrophosphate extraction, these AgCNPs were extracted efficiently from soils. Then, multistep selective dissolution of Ag NPs, AgCl NPs, and whole Ag NPs/AgCl NPs/Ag2S NPs was achieved by 1% (v/v) H2O2, 5% (v/v) NH3·H2O, and 10 mM thiourea in 2% (v/v) acetic acid, respectively. Finally, the particle number concentration and size distribution of AgCNPs in the extracts and the remaining AgCNP particle number concentration after each dissolution were determined by single-particle inductively coupled plasma mass spectroscopy for speciation of the dominant AgCNPs. AgCNPs were detected in all five soil samples with the concentrations of 0.23-8.00 × 107 particles/g and sizes of 16-110 nm. Ag2S NPs were the main form of AgCNPs in the examined soils with the percentage range of 53.98-69.19%, followed by AgCl NPs (11.42-23.31%) and Ag NPs (7.78-16.19%). Our method offers a new approach for evaluating the occurrence and potential risk of AgCNPs in environmental soils.


Assuntos
Nanopartículas Metálicas , Prata , Solo/química , Peróxido de Hidrogênio , Nanopartículas Metálicas/química , Análise Espectral , Tamanho da Partícula
15.
Mol Divers ; 27(3): 1427-1436, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35933454

RESUMO

The essential need for the potent anti-tubercular (anti-TB) agents with high selectivity and safety profile prompted us to synthesize a new series of quinazolinyl-bisspirooxindoles. The title compounds were synthesized by one-pot multicomponent [3 + 2] cycloaddition reaction under ultrasonication. Further, in vitro anti-TB activity was evaluated against Mycobacterium tuberculosis H37Rv. Among the screened compounds, two compounds (4q and 4x) showed potent activity with MIC value 1.56 µg/mL and four compounds exhibited significant activity (MIC = 3.125 µg/mL), and also cytotoxicity studies against RAW 264.7 cell lines reveal that most active compounds were less toxic to humans. In addition, in order to demonstrate the inhibitory properties, molecular docking studies were carried out and the results showed that the target compounds have good binding energy and better binding affinity within the active pocket, thus these compounds may consider to be as potent inhibitors toward selective targets.


Assuntos
Antituberculosos , Mycobacterium tuberculosis , Humanos , Simulação de Acoplamento Molecular , Relação Estrutura-Atividade , Testes de Sensibilidade Microbiana , Estrutura Molecular
16.
Luminescence ; 38(2): 116-126, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36563058

RESUMO

Increasingly, studies are using ultrasound to elevate the functional properties of proteins, so the interaction between phenolic compounds and proteins induced by ultrasound needs to be further understood. ß-Lactoglobulin (ß-LG) at pH 8.1, which exists mainly as monomers, was ultrasound treated at 20 kHz ultrasonic intensity and 30% amplitude for 0-5 min and subsequently interacted with resveratrol. Fluorescence data showed that ultrasound pretreatment improved binding constant (Ka ) from (1.62 ± 0.45) × 105 to (9.43 ± 0.55) × 105 M-1 and binding number from 1.13 ± 0.09 to 1.28 ± 0.11 in a static quenching mode. Fluorescence resonance energy transfer (FRET) analysis indicated that resveratrol bound to the surface hydrophobic pocket of native and treated proteins with no obvious changes in energy transfer efficiency (E) and Föster's distance (r). Thermodynamic parameters indicated that ultrasonication shifted the main driving force from the hydrophobic force for native and 1-min treated ß-LG to van der Waals forces and hydrogen bonding for both 3-min and 5-min treated proteins. Ultrasonication and resveratrol addition generated significant differences in surface hydrophobicity and the surface charge of the protein (P < 0.05), whereas they had little influence on the secondary structure of ß-LG. Compared with the native ß-LG/resveratrol complex, ultrasound-treated protein complexes showed significantly stronger 2,2-azinobis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) scavenging capacity (P < 0.05), and kept relatively stable after 180-min irradiation. Data provided by this study can lead to a better comprehension of the structure and molecular events occurring during the complexing process between an ultrasound-pretreated protein with polyphenol.


Assuntos
Transferência Ressonante de Energia de Fluorescência , Lactoglobulinas , Resveratrol , Lactoglobulinas/química , Estrutura Secundária de Proteína , Ligação Proteica
17.
Sensors (Basel) ; 23(16)2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37631712

RESUMO

Structural health monitoring is crucial for ensuring the safety and reliability of civil infrastructures. Traditional monitoring methods involve installing sensors across large regions, which can be costly and ineffective due to the sensors damage and poor compliance with structural members. This study involves systematically varying the graphene nanoplatelets (GNPs) concentration and analyzing the strength performance and piezoresistive behavior of the resulting composites. Two different composites having natural and recycled sands with varying percentages of GNPs as 2%, 4%, 6%, and 8% were prepared. Dispersion of GNPs was performed in superplasticizer and then ultrasonication was employed by using an ultrasonicator. The four-probe method was utilized to establish the piezoresistive behavior. The results revealed that the compressive strength of mortar cubes with natural sand was increased up to a GNP content of 6%, beyond which it started to decline. In contrast, specimens with recycled sand showed a continuous decrease in the compressive strength. Furthermore, the electrical resistance stability was observed at 4% for both natural and recycled sands specimens, exhibiting linearity between the frictional change in the resistivity and compressive strain values. It can be concluded from this study that the use of self-sensing sustainable cementitious composites could pave their way in civil infrastructures.

18.
Drug Dev Ind Pharm ; 49(9): 590-600, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37733474

RESUMO

OBJECTIVE: The primary objective of this study was to develop nanostructured lipid carriers of donepezil hydrochloride (DNZ HCl) for effective management of Alzheimer's disease (AD). SIGNIFICANCE: Intranasal administration of DNZ NLC containing Nigella sativa (NS) oil as a liquid lipid may significantly improve nasal penetration and deliver the drug directly to the brain avoiding blood brain barrier (BBB). METHOD: High pressure homogenization was used to prepare nanostructured lipid carriers (NLCs), followed by ultrasonication. Glyceryl monostearate (GMS), Tween 80, and Poloxamer 407 were used as solid lipid, surfactant and co-surfactant respectively, whereas, Nigella sativa oil was used as a liquid lipid. RESULT: The particle size, polydispersity index and zeta potential were found to be 107.4 ± 2.64 nm, 0.25 ± 0.04 and -41.7 mV. The entrapment efficiency and drug content were found to be 70.20% and 89.05% respectively. After intranasal administration of Donepezil hydrochloride (DNZ HCl) loaded NLC's, the maximum concentrations (Cmax) of 4.597 µg/mL in brain and 2.2583 µg/mL in blood was achieved after 1 h (Tmax). CONCLUSION: The formulated DNZ HCl loaded NLCs significantly improved nasal penetration and enhanced drug distribution in brain resulting in a potentially effective intranasal drug delivery system for the effective management of Alzheimer's disease.


Assuntos
Doença de Alzheimer , Nanoestruturas , Humanos , Portadores de Fármacos , Donepezila , Doença de Alzheimer/tratamento farmacológico , Lipídeos , Tensoativos , Tamanho da Partícula
19.
Int J Mol Sci ; 24(18)2023 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-37762503

RESUMO

á¼°-carrageenan is a linear macroalgal polysaccharide that is well known for its antiviral bioactivity. Although it is considered a candidate for antiviral therapeutics, its application is highly limited due to its low solubility and high viscosity, which lower its adsorption efficiency. With the aim of deriving an active á¼°-carrageenan fragment with an improved adsorption capacity, we studied the effects of ultrasonication on structural changes in á¼°-carrageenan with respect to changes in its bioactivity against herpesviruses. An FTIR analysis revealed that ultrasonication increased the hydrophilicity of á¼°-carrageenan without changing its functional groups, and a rheological analysis demonstrated that it gradually decreased the strength of the polysaccharide gel, which completely lost its gel structure and formed small nanoparticles after 30 min of ultrasonication. Concomitantly with these physicochemical changes, a plaque assay revealed that longer ultrasonication increased the antiviral activity of á¼°-carrageenan against two herpesviruses, namely, HSV-1 and VZV. Finally, we separated the 30-min ultrasonicated á¼°-carrageenan into four fractions and found that fractions with a lower molecular weight were significantly less active against both herpesviruses than those with a higher molecular weight. Our findings show that ultrasonication induces physicochemical changes in á¼°-carrageenan that increase its antiviral bioactivity.

20.
J Environ Manage ; 340: 117960, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37119622

RESUMO

Lactose in cheese whey wastewater (CWW) makes it difficult to degrade under normal conditions. The effect of ultra-sonication (US), ozonation and enzymatic hydrolysis on increasing the bioavailability of organic matter in CWW and biogas production were evaluated. The pre-treatment conditions were: specific energy input varied from 2130 to 8773KJ/KgTS for a sonication time of 4.5-18.5 min, Ozone (O3) dosages ranging from 0.03 to 0.045gO3/gTS were applied for 4-16 min, pH (3.8-7.1), temperature (35°C-55°C), enzyme dosage (0.18-0.52%), was operated from 7.75 to 53 min for enzymatic hydrolysis by ß-galactosidase. The results of the US reported a maximum sCOD solubilisation of 77.15% after 18.5 min of operation, while the corresponding values for ozonation and enzymatic methods were 64.8% at 16 min and 54.79%, respectively. The organic matter degradation rates evaluated in terms of protein and lactose hydrolysis were 68.78%,46.03%; 47.83%,16.15% and 54.22%,86.2%respectively, for US, ozonation and enzymatic methods. The cumulative methane yield for sonicated, ozonised and enzymatically hydrolysed samples were 412.4 ml/g VS, 361.2 ml/g VS and 432.3mlCH4/gVS, respectively. Regardless of the lower COD solubilisation rates attained, enzymatic pre-treatment showed maximum methane generation compared to US and ozonation. This could be attributable to the increased activity of ß-galactosidase in hydrolysing whey lactose. The energy calculations revealed that the pre-conditioning of organic-rich CWW with enzymatic hydrolysis is more effective and efficient, yielding a net energy gain (gross output energy-input energy) of 9166.7 KJ and an energy factor (ratio of output to input energy) of 6.67. The modified Gompertz model well simulated all experimental values.


Assuntos
Queijo , Ozônio , Soro do Leite/metabolismo , Esgotos , Ultrassom/métodos , Anaerobiose , Lactose , Águas Residuárias , beta-Galactosidase/metabolismo , Metano , Reatores Biológicos
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