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1.
Lab Chip ; 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39143844

RESUMEN

Formation of bacterial films on structural surfaces often leads to severe contamination of medical devices, hospital equipment, implant materials, etc., and antimicrobial resistance of microorganisms has indeed become a global health issue. Therefore, effective therapies for controlling infectious and pathogenic bacteria are urgently needed. Being a promising active method for this purpose, surface acoustic waves (SAWs) have merits such as nanoscale earthquake-like vibration/agitation/radiation, acoustic streaming induced circulations, and localised acoustic heating effect in liquids. However, only a few studies have explored controlling bacterial growth and inactivation behaviour using SAWs. In this study, we proposed utilising piezoelectric thin film-based SAW devices on a silicon substrate for controlling bacterial growth and inactivation with and without using ZnO micro/nanostructures. Effects of SAW powers on bacterial growth for two types of bacteria, i.e., E. coli and S. aureus, were evaluated. Varied concentrations of ZnO tetrapods were also added into the bacterial culture to study their effects and the combined antimicrobial effects along with SAW agitation. Our results showed that when the SAW power was below a threshold (e.g., about 2.55 W in this study), the bacterial growth was apparently enhanced, whereas the further increase of SAW power to a high power caused inactivation of bacteria. Combination of thin film SAWs with ZnO tetrapods led to significantly decreased growth or inactivation for both E. coli and S. aureus, revealing their effectiveness for antimicrobial treatment. Mechanisms and effects of SAW interactions with bacterial solutions and ZnO tetrapods have been systematically discussed.

3.
RSC Adv ; 14(30): 21654, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38979474

RESUMEN

Expression of concern for 'High performance flexible supercapacitors based on secondary doped PEDOT-PSS-graphene nanocomposite films for large area solid state devices' by Syed Khasim et al., RSC Adv., 2020, 10, 10526-10539, https://doi.org/10.1039/D0RA01116A.

4.
Chemosphere ; 361: 142380, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38763401

RESUMEN

Due to weather and working/operational conditions, plastic degradation produces toxic and non-biodegradable nano and microplastics (N/M-Ps, ranging from 10 nm to 5 mm), and over time these N/M-Ps have integrated with the human cycle through ingestion and inhalation. These N/M-Ps, as serious emerging pollutants, are causing considerable adverse health issues due to up-taken by the cells, tissue, and organs, including the brain. It has been proven that N/M-Ps can cross the blood-brain barrier (via olfactory and blood vessels) and affect the secretion of neuroinflammatory (cytokine and chemokine), transporters, and receptor markers. Neurotoxicity, neuroinflammation, and brain injury, which may result in such scenarios are a serious concern and may cause brain disorders. However, the related pathways and pathogenesis are not well-explored but are the focus of upcoming emerging research. Therefore, as a focus of this editorial, well-organized multidisciplinary research is required to explore associated pathways and pathogenesis, leading to brain mapping and nano-enabled therapeutics in acute and chronic N/M - Ps exposure.


Asunto(s)
Encéfalo , Microplásticos , Humanos , Encéfalo/metabolismo , Microplásticos/toxicidad , Barrera Hematoencefálica/metabolismo , Contaminantes Ambientales/toxicidad , Plásticos , Nanopartículas/toxicidad
5.
Beilstein J Nanotechnol ; 15: 367-375, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38590431

RESUMEN

Desired modifications of surfaces at the nanoscale may be achieved using energetic ion beams. In the present work, a complete study of self-assembled ripple pattern fabrication on Si and Ge by 100 keV Ar+ ion beam bombardment is discussed. The irradiation was performed in the ion fluence range of ≈3 × 1017 to 9 × 1017 ions/cm2 and at an incident angle of θ ≈ 60° with respect to the surface normal. The investigation focuses on topographical studies of pattern formation using atomic force microscopy, and induced damage profiles inside Si and Ge by Rutherford backscattering spectrometry and transmission electron microscopy. The ripple wavelength was found to scale with ion fluence, and energetic ions created more defects inside Si as compared to that of Ge. Although earlier reports suggested that Ge is resistant to structural changes upon Ar+ ion irradiation, in the present case, a ripple pattern is observed on both Si and Ge. The irradiated Si and Ge targets clearly show visible damage peaks between channel numbers (1000-1100) for Si and (1500-1600) for Ge. The clustering of defects leads to a subsequent increase of the damage peak in irradiated samples (for an ion fluence of ≈9 × 1017 ions/cm2) compared to that in unirradiated samples.

6.
J Mater Chem B ; 12(12): 2950-2984, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38426529

RESUMEN

Thin-film nano-architecting is a promising approach that controls the properties of nanoscale surfaces to increase their interdisciplinary applications in a variety of fields. In this context, zinc oxide (ZnO)-based various nano-architectures (0-3D) such as quantum dots, nanorods/nanotubes, nanothin films, tetrapods, nanoflowers, hollow structures, etc. have been extensively researched by the scientific community in the past decade. Owing to its unique surface charge transport properties, optoelectronic properties and reported biomedical applications, ZnO has been considered as one of the most important futuristic bio-nanomaterials. This review is focused on the design/synthesis and engineering of 0-3D nano-architecture ZnO-based thin films and coatings with tunable characteristics for multifunctional biomedical applications. Although ZnO has been extensively researched, ZnO thin films composed of 0-3D nanoarchitectures with promising thin film device bio-nanotechnology applications have rarely been reviewed. The current review focuses on important details about the technologies used to make ZnO-based thin films, as well as the customization of properties related to bioactivities, characterization, and device fabrication for modern biomedical uses that are relevant. It features biosensing, tissue engineering/wound healing, antibacterial, antiviral, and anticancer activity, as well as biomedical diagnosis and therapy with an emphasis on a better understanding of the mechanisms of action. Eventually, key issues, experimental parameters and factors, open challenges, etc. in thin film device fabrications and applications, and future prospects will be discussed, followed by a summary and conclusion.


Asunto(s)
Nanoestructuras , Nanotubos , Óxido de Zinc , Óxido de Zinc/química , Nanotecnología , Nanotubos/química , Nanoestructuras/química , Propiedades de Superficie
7.
Biomed Pharmacother ; 171: 116160, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38237351

RESUMEN

The aggrandised advancement in utility of advanced day-to-day materials and nanomaterials has raised serious concern on their biocompatibility with human and other biotic members. In last few decades, understanding of toxicity of these materials has been given the centre stage of research using many in vitro and in vivo models. Zebrafish (Danio rerio), a freshwater fish and a member of the minnow family has garnered much attention due to its distinct features, which make it an important and frequently used animal model in various fields of embryology and toxicological studies. Given that fertilization and development of zebrafish eggs take place externally, they serve as an excellent model organism for studying early developmental stages. Moreover, zebrafish possess a comparable genetic composition to humans and share almost 70% of their genes with mammals. This particular model organism has become increasingly popular, especially for developmental research. Moreover, it serves as a link between in vitro studies and in vivo analysis in mammals. It is an appealing choice for vertebrate research, when employing high-throughput methods, due to their small size, swift development, and relatively affordable laboratory setup. This small vertebrate has enhanced comprehension of pathobiology and drug toxicity. This review emphasizes on the recent developments in toxicity screening and assays, and the new insights gained about the toxicity of drugs through these assays. Specifically, the cardio, neural, and, hepatic toxicology studies inferred by applications of nanoparticles have been highlighted.


Asunto(s)
Nanoestructuras , Pez Cebra , Animales , Humanos , Modelos Animales , Hígado , Mamíferos
8.
Small ; 20(24): e2309572, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38155584

RESUMEN

Exploring combinatorial materials, as well as rational device configuration design, are assumed to be the key strategies for deploying versatile electrochemical devices. MXene sheets have revealed a high hydrophilic surface with proper mechanical and electrical characteristics, rendering them supreme additive candidates to integrate in electrospun electrochemical power tools. The synergetic effects of MXene 2D layers with the nanofibrous networks can boost actuator responsive ability, battery capacity retention, fuel cell stability, sensor sensitivity, and supercapacitor areal capacitance. Their superior mechanical features can be endowed to the electrospun layers through the embedding of the MXene additive. In this review, the preparation and inherent features of the MXene configurations are briefly evaluated. The fabrication and overall performance of the MXene-loaded nanofibers applicable in electrochemical actuators, batteries, fuel cells, sensors, and supercapacitors are comprehensively figured out. Eventually, an outlook on the future development of MXene-based electrospun composites is presented. A substantial focus has been devoted to date to engineering conjugated MXene and electrospun fibrous frames. The potential performance of the MXene-decorated nanofibers presents a bright future of nanoengineering toward technological growth. Meanwhile, a balance between the pros and cons of the synthesized MXene composite layers is worthwhile to consider in the future.

9.
Biotechnol Adv ; 69: 108267, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37813174

RESUMEN

Traditionally, recombinant protein production has been done in several expression hosts of bacteria, fungi, and majorly CHO (Chinese Hamster Ovary) cells; few have high production costs and are susceptible to harmful toxin contamination. Green algae have the potential to produce recombinant proteins in a more sustainable manner. Microalgal diversity leads to offer excellent opportunities to produce glycosylated antibodies. An antibody with humanized glycans plays a crucial role in cellular communication that works to regulate cells and molecules, to control disease, and to stimulate immunity. Therefore, it becomes necessary to understand the role of abiotic factors (light, temperature, pH, etc.) in the production of bioactive molecules and molecular mechanisms of product synthesis from microalgae which would lead to harnessing the potential of algal bio-refinery. However, the potential of microalgae as the source of bio-refinery has been less explored. In the present review, omics approaches for microalgal engineering, methods of humanized glycoproteins production focusing majorly on N-glycosylation pathways, light-based regulation of glycosylation machinery, and production of antibodies with humanized glycans in microalgae with a major emphasis on modulation of post-translation machinery of microalgae which might play a role in better understanding of microalgal potential as a source for antibody production along with future perspectives.


Asunto(s)
Biotecnología , Polisacáridos , Cricetinae , Animales , Glicosilación , Células CHO , Cricetulus , Proteínas Recombinantes/genética
10.
ACS Appl Mater Interfaces ; 15(30): 36096-36106, 2023 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-37471608

RESUMEN

Oral healthcare monitoring is a vital aspect of identifying and addressing oral dental problems including tooth decay, gum pain, and oral cancer. Day by day, healthcare facilities and regular checkups are becoming more costly and time-consuming. In this context, consumers are moving toward advanced technology, such as bite sensors, to obtain regular data about their occlusal chewing patterns and strength. The triboelectric nanogenerator (TENG) can potentially eliminate the need for a battery by simply converting abundant vibrations from nature or human motion into electrical energy. In this work, biomaterials are obtained from biowastes such as cellulose from wood waste, chitosan from crab shells, and gelatin from fish scales. All wastes are biodegradable, and our work aims at sustainability and waste hierarchy. The single electrode mode-based TENG was designed and fabricated using biodegradable poly(vinyl alcohol) (PVA)-biomaterial composites, rice paper as a substrate, and edible silver leaf as an electrode. The highest electrical output was obtained for PVA/chitosan 10 wt % composite-based TENG (PC10) of about 20 V, 200 nA, and 12 nC. The biomechanical energy harvesting was measured, and powering of LED was demonstrated using a PC10 TENG device. A biocompatible bite sensor based on the TENG was used to measure the biting force of a dummy teeth model to demonstrate its potential use in dental health applications. It indicates the promising future value of disposable oral medication devices without any invasive surgery or injection.


Asunto(s)
Quitosano , Animales , Humanos , Salud Bucal , Materiales Biocompatibles , Celulosa , Suministros de Energía Eléctrica
11.
Mater Today Bio ; 21: 100701, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37415846

RESUMEN

Alzheimer's disease (AD) is a type of dementia that affects a vast number of people around the world, causing a great deal of misery and death. Evidence reveals a relationship between the presence of soluble Aß peptide aggregates and the severity of dementia in Alzheimer's patients. The BBB (Blood Brain Barrier) is a key problem in Alzheimer's disease because it prevents therapeutics from reaching the desired places. To address the issue, lipid nanosystems have been employed to deliver therapeutic chemicals for anti-AD therapy in a precise and targeted manner. The applicability and clinical significance of lipid nanosystems to deliver therapeutic chemicals (Galantamine, Nicotinamide, Quercetin, Resveratrol, Curcumin, HUPA, Rapamycin, and Ibuprofen) for anti-AD therapy will be discussed in this review. Furthermore, the clinical implications of the aforementioned therapeutic compounds for anti-AD treatment have been examined. Thus, this review will pave the way for researchers to fashion therodiagnostics approaches based on nanomedicine to overcome the problems of delivering therapeutic molecules across the blood brain barrier (BBB).

12.
Int J Biol Macromol ; 247: 125606, 2023 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-37406894

RESUMEN

Nature-derived or biologically encouraged hydrogels have attracted considerable interest in numerous biomedical applications owing to their multidimensional utility and effectiveness. The internal architecture of a hydrogel network, the chemistry of the raw materials involved, interaction across the interface of counter ions, and the ability to mimic the extracellular matrix (ECM) govern the clinical efficacy of the designed hydrogels. This review focuses on the mechanistic viewpoint of different biologically driven/inspired biomacromolecules that encourages the architectural development of hydrogel networks. In addition, the advantage of hydrogels by mimicking the ECM and the significance of the raw material selection as an indicator of bioinertness is deeply elaborated in the review. Furthermore, the article reviews and describes the application of polysaccharides, proteins, and synthetic polymer-based multimodal hydrogels inspired by or derived from nature in different biomedical areas. The review discusses the challenges and opportunities in biomaterials along with future prospects in terms of their applications in biodevices or functional components for human health issues. This review provides information on the strategy and inspiration from nature that can be used to develop a link between multimodal hydrogels as the main frame and its utility in biomedical applications as the primary target.


Asunto(s)
Hidrogeles , Polímeros , Humanos , Hidrogeles/química , Polímeros/química , Proteínas/uso terapéutico , Materiales Biocompatibles/química , Polisacáridos/química
13.
Small ; 19(44): e2303340, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37386778

RESUMEN

2D graphene the most investigated structures from nanocarbon family studied in the last three decades. It is projected as an excellent material useful for quantum computing, artificial intelligence, and next generation advanced technologies. Graphene exists in several forms and its extraordinary thermal, mechanical, and electronic properties, principally depend on the kind of perfection of the hexagonal atomic lattice. Defects are always considered as undesired components but certain defects in graphene could be an asset for electrochemistry and quantum electronics due to the engineered electronclouds and quantum tunnelling. The authors carefully discuss the Stone-Wales imperfections in graphene and its derivatives comprehensively. A specific emphasis is focused on the experimental and theoretical aspects of the Stone-Wales defects in graphene with respect to structure-property relationships. The corroboration of extrinsic defects like external atomic doping, functionalization, edge distortion in the graphene consisting of Stone-Wales imperfections, which are very significant in designing graphene-based electronic devices, are summarized.

14.
J Mater Chem B ; 11(26): 6159-6160, 2023 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-37341443

RESUMEN

Correction for 'Lipid nanoparticle-based formulations for high-performance dentistry applications' by Isha Mutreja et al., J. Mater. Chem. B, 2023, https://doi.org/10.1039/D3TB00431G.

15.
J Mater Chem B ; 11(26): 5990-6023, 2023 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-37278481

RESUMEN

In the growing field of dentistry research, there is significant scope for investigating novel and high-performance functional biomaterials for dental care, mainly to combat oral health diseases. Considering the growing economic burden on dental care, there is an urgent need to investigate affordable and biologically acceptable functional antibacterial nanostructures capable of exhibiting desired pharmacological properties. Although a wide range of materials has been investigated for dentistry applications, their acceptability and scaling-up clinical acceptance remain a challenge to cytotoxicity and alterations in cellular function. To address these challenges, nanolipids are emerging as potential materials to develop the next generation of treatment modalities for dental care and oral diseases. However, there is a need to cover the knowledge gap between developing good quality nanolipid formulations, their introduction in dental research, establishing a track from laboratory to clinical application, exploring associated risks, and proposing step-by-step systematic research to obtain FDA approval for recommending nanolipids for next-generation systems for dentistry applications. This study also summarizes the outcomes of the literature carefully and critically to provide a clear view about selecting an appropriate nanolipid system to manage a targeted dental issue. These programmable nanolipids can be designed and developed using optimized chemistry and pharmacology to be used in a controlled manner by manipulating their responsiveness according to the demand of targeted disease management, i.e., a programmable system. The future of this research, keeping clinical adaptability as a focus, is also discussed in this review, along with the possible challenges and possible alternative approaches.


Asunto(s)
Liposomas , Salud Bucal , Humanos , Composición de Medicamentos , Odontología
17.
Int J Biol Macromol ; 242(Pt 1): 124703, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37141967

RESUMEN

The wide spectrum of applications provided by curcumin has attracted researchers worldwide to identify its molecular targets and employ it in various biomedical applications. The present research work focuses on the development of a Butea monosperma gum-based hydrogel encapsulated with curcumin and further employing it for two diverse applications, i.e., drug delivery and anti-bacterial application. A central composite design was utilized for the optimization of significant process variables to achieve maximum swelling. A maximum of 662 % swelling was attained at initiator (0.06 g), monomer (3 ml), crosslinker (0.08 g), solvent (14 ml), and time (60 s). Furthermore, the characterization of the synthesized hydrogel was performed via FTIR, SEM, TGA, H1-NMR, and XRD analysis. Various important properties like swelling rate under different solutions, water retention capacity, re-swelling capability, porosity, and density measurement suggested that the prepared hydrogel exhibited a highly stable crosslinked network with high porosity (0.23) and density (62.5 g/cm3) values. The encapsulation efficiency of curcumin in the hydrogel was reported to be 93 % and 87.3 %, respectively, wherein BM-g-poly(AA) âˆ¼ Cur exhibited excellent sustained pH-responsive site release of curcumin at two different pH values, with the maximum amount of release taking place at pH 7.4 (792 ppm) and a minimum at pH 5 (550 ppm) due to the lesser ionization of the functional groups present in the hydrogel at a lower pH value. Additionally, the results from the pH shock studies indicated our material to be stable and efficient even with fluctuations in pH, resulting in the optimal amount of drug release at each pH range. Furthermore, anti-bacterial studies revealed that the synthesized BM-g-poly(AA) âˆ¼ Cur was effective against both gram-negative and gram-positive bacteria, with maximum values of zones of inhibition of 16 mm in diameter, thereby showing the best results in comparison to the already developed matrices till date. As a result, the newly discovered BM-g-poly(AA) âˆ¼ Cur properties reflect the hydrogel network's suitability for drug release and anti-bacterial applications.


Asunto(s)
Butea , Curcumina , Curcumina/farmacología , Curcumina/química , Hidrogeles/química , Excipientes/química , Portadores de Fármacos/química , Liberación de Fármacos
18.
Environ Res ; 229: 115933, 2023 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-37080272

RESUMEN

Metal/metal oxide nano systems (M-NSs) of tunable and manipulative properties are emerging suitable for cancer management via immunity development, early-stage diagnosis, nanotherapeutics, and targeted drug delivery systems. However, noticeable toxicity, off-targeted actions, lacking biocompatibility, and being expensive limit their acceptability. Moreover, involving high energy (top-down routes) and hazardous chemicals (bottom-up chemical routes) is altering human cycle. To manage such challenges, biomass (plants, microbes, animals) and green chemistry-based M-NSs due to scalability, affordability, are cellular, tissue, and organ acceptability are emerging as desired biogenic M-NSs for cancer management with enhanced features. The state-of-art and perspective of green metal/metal oxide nano systems (GM-NSs) as an efficient anti-cancer agent including, imaging, immunity building elements, site-specific drug delivery, and therapeutics developments are highlighted in this review critically. It is expected that this report will serve as guideline for design and develop high-performance GM-NSs for establishing them as next-generation anti-cancer agent capable to manage cancer in personalized manner.


Asunto(s)
Antineoplásicos , Nanopartículas del Metal , Neoplasias , Animales , Humanos , Antineoplásicos/uso terapéutico , Antineoplásicos/química , Metales , Sistemas de Liberación de Medicamentos , Neoplasias/tratamiento farmacológico , Óxidos , Nanopartículas del Metal/uso terapéutico , Nanopartículas del Metal/toxicidad , Nanopartículas del Metal/química
19.
Small ; 19(25): e2300847, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36929123

RESUMEN

The ocean holds vast potential as a renewable energy source, but harnessing its power has been challenging due to low-frequency and high-amplitude stimulation. However, hybrid nanogenerators (HNGs) offer a promising solution to convert ocean energy into usable power efficiently. With their high sensitivity and flexible design, HNGs are ideal for low-frequency environments and remote ocean regions. Combining triboelectric nanogenerators (TENGs) with piezoelectric nanogenerators (PENGs) and electromagnetic nanogenerators (EMGs) creates a unique hybrid system that maximizes energy harvesting. Ultimately, hybrid energy-harvesting systems offer a sustainable and reliable solution for growing energy needs. This study provides an in-depth review of the latest research on ocean energy harvesting by hybrid systems, focusing on self-powered applications. The article also discusses primary hybrid designs for devices, powering self-powered units such as wireless communication systems, climate monitoring systems, and buoys as applications. The potential of HNGs is enormous, and with rapid advancements in research and fabrication, these systems are poised to revolutionize ocean energy harvesting. It outlines the pros and cons of HNGs and highlights the major challenges that must be overcome. Finally, future outlooks for hybrid energy harvesters are also discussed.

20.
ACS Biomater Sci Eng ; 9(3): 1352-1361, 2023 03 13.
Artículo en Inglés | MEDLINE | ID: mdl-36776118

RESUMEN

The glaucoma burden increases continuously and is estimated to affect more than 100 million people by 2040. As there is currently no cure to restore the optic nerve damage caused by glaucoma, the only controllable parameter is the intraocular pressure (IOP). In recent years, minimally invasive glaucoma surgery (MIGS) has emerged as an alternative to traditional treatments. It uses micro-sized drainage stents that are inserted through a small incision, minimizing the trauma to the tissue and reducing surgical and postoperative recovery time. However, a major challenge for MIGS devices is foreign body reaction and fibrosis, which can lead to a complete failure of the device. In this work, the antifibrotic potential of tetrapodal ZnO (t-ZnO) microparticles used as an additive is elucidated by using rat embryonic fibroblasts as a model. A simple, direct solvent-free process for the fabrication of stents with an outer diameter of 200-400 µm is presented, in which a high amount of t-ZnO particles (45-75 wt %) is mixed into polydimethylsiloxane (PDMS) and a highly viscous polymer/particle mixture is extruded. The fabricated stents possess increased elastic modulus compared to pure PDMS while remaining flexible to adapt to the curvature of an eye. In vitro experiments showed that the fibroblast cell viability was inhibited to 43 ± 3% when stents with 75 wt % t-ZnO were used. The results indicate that cell inhibiting properties can be attributed to an increased amount of protruding t-ZnO particles on the stent surface, leading to an increase in local contacts with cells and a disruption of the cell membrane. As a secondary mechanism, the released Zn ions could also contribute to the cell-inhibiting properties in the close vicinity of the stent surface. Overall, the fabrication method and the antifibrotic and mechanical properties of developed stents make them promising for application in MIGS.


Asunto(s)
Glaucoma , Stents , Glaucoma/cirugía , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Animales , Ratas , Óxido de Zinc
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