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1.
Circulation ; 149(25): 2002-2020, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38885303

RESUMO

Myocardial infarction is a cardiovascular disease characterized by a high incidence rate and mortality. It leads to various cardiac pathophysiological changes, including ischemia/reperfusion injury, inflammation, fibrosis, and ventricular remodeling, which ultimately result in heart failure and pose a significant threat to global health. Although clinical reperfusion therapies and conventional pharmacological interventions improve emergency survival rates and short-term prognoses, they are still limited in providing long-lasting improvements in cardiac function or reversing pathological progression. Recently, cardiac patches have gained considerable attention as a promising therapy for myocardial infarction. These patches consist of scaffolds or loaded therapeutic agents that provide mechanical reinforcement, synchronous electrical conduction, and localized delivery within the infarct zone to promote cardiac restoration. This review elucidates the pathophysiological progression from myocardial infarction to heart failure, highlighting therapeutic targets and various cardiac patches. The review considers the primary scaffold materials, including synthetic, natural, and conductive materials, and the prevalent fabrication techniques and optimal properties of the patch, as well as advanced delivery strategies. Last, the current limitations and prospects of cardiac patch research are considered, with the goal of shedding light on innovative products poised for clinical application.


Assuntos
Infarto do Miocárdio , Humanos , Infarto do Miocárdio/terapia , Infarto do Miocárdio/fisiopatologia , Animais , Alicerces Teciduais
2.
Rev Physiol Biochem Pharmacol ; 184: 121-157, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35266054

RESUMO

Chitosan is a natural polysaccharide widespread in nature. It has many unique and attractive properties for the pharmaceutical field: it is biodegradable, safe, hypoallergenic, biocompatible with the body, free of toxicity, with proven anticholesterolemic, antibacterial, and antimycotic action. In this review we highlighted the physical, chemical, mechanical, mucoadhesive, etc. properties of chitosan to be taken into account when obtaining various pharmaceutical forms. The methods by which the pharmaceutical forms based on chitosan are obtained are very extensive, and in this study only the most common ones were presented.


Assuntos
Quitosana , Humanos , Quitosana/química , Preparações Farmacêuticas
3.
Arterioscler Thromb Vasc Biol ; 44(3): e66-e81, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38174560

RESUMO

Peripheral artery disease is an atherosclerotic disease associated with limb ischemia that necessitates limb amputation in severe cases. Cell therapies comprised of adult mononuclear or stromal cells have been clinically tested and show moderate benefits. Bioengineering strategies can be applied to modify cell behavior and function in a controllable fashion. Using mechanically tunable or spatially controllable biomaterials, we highlight examples in which biomaterials can increase the survival and function of the transplanted cells to improve their revascularization efficacy in preclinical models. Biomaterials can be used in conjunction with soluble factors or genetic approaches to further modulate the behavior of transplanted cells and the locally implanted tissue environment in vivo. We critically assess the advances in bioengineering strategies such as 3-dimensional bioprinting and immunomodulatory biomaterials that can be applied to the treatment of peripheral artery disease and then discuss the current challenges and future directions in the implementation of bioengineering strategies.


Assuntos
Bioengenharia , Doença Arterial Periférica , Adulto , Humanos , Bioengenharia/métodos , Doença Arterial Periférica/terapia , Materiais Biocompatíveis , Terapia Baseada em Transplante de Células e Tecidos , Procedimentos Cirúrgicos Vasculares , Resultado do Tratamento
4.
Proc Natl Acad Sci U S A ; 119(8)2022 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-35193961

RESUMO

Quantum metrology enables some of the most precise measurements. In the life sciences, diamond-based quantum sensing has led to a new class of biophysical sensors and diagnostic devices that are being investigated as a platform for cancer screening and ultrasensitive immunoassays. However, a broader application in the life sciences based on nanoscale NMR spectroscopy has been hampered by the need to interface highly sensitive quantum bit (qubit) sensors with their biological targets. Here, we demonstrate an approach that combines quantum engineering with single-molecule biophysics to immobilize individual proteins and DNA molecules on the surface of a bulk diamond crystal that hosts coherent nitrogen vacancy qubit sensors. Our thin (sub-5 nm) functionalization architecture provides precise control over the biomolecule adsorption density and results in near-surface qubit coherence approaching 100 µs. The developed architecture remains chemically stable under physiological conditions for over 5 d, making our technique compatible with most biophysical and biomedical applications.


Assuntos
Técnicas Biossensoriais/métodos , Diamante/química , Nanotecnologia/métodos , Técnicas Biossensoriais/instrumentação , Espectroscopia de Ressonância Magnética/métodos , Nanopartículas/química , Nitrogênio/química
5.
Small ; : e2402899, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38949406

RESUMO

Nanomaterials associated with plant growth and crop cultivation revolutionize traditional concepts of agriculture. However, the poor reiterability of these materials in agricultural applications necessitates the development of environmentally-friendly approaches. To address this, biocompatible gelatin nanoparticles (GNPs) as nanofertilizers with a small size (≈150 nm) and a positively charged surface (≈30 mV) that serve as a versatile tool in agricultural practices is designed. GNPs load agrochemical agents to improve maintenance and delivery. The biocompatible nature and small size of GNPs ensure unrestricted nutrient absorption on root surfaces. Furthermore, when combined with pesticides, GNPs demonstrate remarkable enhancements in insecticidal (≈15%) and weed-killing effects (≈20%) while preserving the efficacy of the pesticide. That GNPs have great potential for use in sustainable agriculture, particularly in inducing plant growth, specifically plant root growth, without fertilization and in enhancing the functions of agrochemical agents is proposed. It is suggested conceptual applications of GNPs in real-world agricultural practices.

6.
Small ; 20(5): e2305126, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37735144

RESUMO

It is always challenging to integrate multiple functions into one material system. However, those materials/devices will address society's critical global challenges and technological demands if achieved with innovative design strategies and engineering. Here, one such material with a broader spectrum of desired properties appropriate for seven applications is identified and explored, and a glucose-sensing-triggered energy-storage mechanism is demonstrated. To date, the Titanium (Ti)-Zinc (Zn) binary alloys are investigated only as mixed phases and for a maximum of three applications. In contrast, the novel single phase of structurally stable 50 Ti-50 Zn (Ti0.5 Zn0.5 ) is synthesized and proven suitable for seven emerging applications. Interestingly, it is thermally stable up to 750 °C and possesses excellent mechanical, tribological properties and corrosion resistance. While exceptional biocompatibility is evident even up to a concentration of 500 µg mL-1 , the antibacterial activity against E. coli is also seen. Further, rapid detection and superior selectivity for glucose, along with supercabattery behavior, unambiguously demonstrate that this novel monophase is a remarkable multifunctional material than the existing mixed-phase Ti-Zn compounds. The coin-cell supercapacitor shows outstanding stability up to 30 000 cycles with >100% retention capacity. This allows us to prototype a glucose-sensing-triggered energy-storage-device system for wearable point-of-care diagnostic applications.

7.
Small ; : e2404426, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39058212

RESUMO

Solution-processed colloidal III-V semiconductor-based quantum dots (QDs) represent promising and environmentally-friendly alternatives to Cd-based QDs in the realms of optoelectronics and biological applications. While InP-based core-shell QDs have demonstrated efficient light-emitting diode (LED) performance in the visible region, achieving deep-red emission (above 700 nm) with a narrow linewidth has proven challenging. Herein, the study presents a novel strategy for synthesizing InP/ZnSe/ZnS core-shell-shell QDs tailored for emission in the first biological transparency window. The resulting QDs exhibit an emission wavelength up to 725 nm with a narrow peak full width at half maximum (FWHM) down to 107 meV (45 nm). To enhance the biocompatibility and chemical stability of the QDs, their surface is further capped with a layer of amorphous alumina resulting in an InP/ZnSe/ZnS/Al2O3 heterostructure. This surface passivation not only ensures environmental- and photostability but also enhances the photoluminescence quantum yield (PLQY). The alumina capping enables the aqueous phase transfer via surface ligand exchange using mercaptopropionic acid (MPA) while maintaining the initial quantum yield. The resulting QDs demonstrate a significant potential for advancing next-generation optoelectronic technologies and bio-applications.

8.
Small ; 20(24): e2307439, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38213007

RESUMO

Neuroprosthetics and brain-machine interfaces are immensely beneficial for people with neurological disabilities, and the future generation of neural repair systems will utilize neuromorphic devices for the advantages of energy efficiency and real-time performance abilities. Conventional synaptic devices are not compatible to work in such conditions. The cerebrospinal fluid (CSF) in the central part of the nervous system is composed of 99% water. Therefore, artificial synaptic devices, which are the fundamental component of neuromorphic devices, should resemble biological nerves while being biocompatible, and functional in high-humidity environments with higher functional stability for real-time applications in the human body. In this work, artificial synaptic devices are fabricated based on gelatin-PEDOT: PSS composite as an active material to work more effectively in a highly humid environment (≈90% relative humidity). These devices successfully mimic various synaptic properties by the continuous variation of conductance, like, excitatory/inhibitory post-synaptic current(EPSC/IPSC), paired-pulse facilitation/depression(PPF/PPD), spike-voltage dependent plasticity (SVDP), spike-duration dependent plasticity (SDDP), and spike-rate dependent plasticity (SRDP) in environments at a relative humidity levels of ≈90%.


Assuntos
Umidade , Animais , Sinapses/fisiologia , Humanos , Plasticidade Neuronal/fisiologia , Proteínas/química
9.
Small ; 20(6): e2306387, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37771189

RESUMO

4D printing recently emerges as an exciting evolution of conventional 3D printing, where a printed construct can quickly transform in response to a specific stimulus to switch between a temporary variable state and an original state. In this work, a photocrosslinkable polyethylene-glycol polyurethane ink is synthesized for light-assisted 4D printing of smart materials. The molecular weight distribution of the ink monomers is tunable by adjusting the copolymerization reaction time. Digital light processing (DLP) technique is used to program a differential swelling response in the printed constructs after humidity variation. Bioactive microparticles are embedded into the ink and the improvement of biocompatibility of the printed constructs is demonstrated for tissue engineering applications. Cell studies reveal above 90% viability in 1 week and ≈50% biodegradability after 4 weeks. Self-folding capillary scaffolds, dynamic grippers, and film actuators are made and activated in a humid environment. The approach offers a versatile platform for the fabrication of complex constructs. The ink can be used in tissue engineering and actuator applications, making the ink a promising avenue for future research.


Assuntos
Tinta , Alicerces Teciduais , Poliuretanos , Engenharia Tecidual/métodos , Hidrogéis , Impressão Tridimensional
10.
Chemistry ; : e202402687, 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-39158121

RESUMO

Generally, an esterase lipase enzyme can hydrolyze specific substrates called esters in an aqueous solution. Herein, we investigate how a G-quadruplex self-assembly affects the hydrolysis equilibrium in reverse. The biocatalyst, lipase, activates the individual building-blocks through fuel consumption, causing them to undergo a higher degree of self-organization into nanofibers within spheres. We have synthesized five peptide-lipid-conjugated guanine base functionalized molecules to explore how the equilibrium can be shifted through reverse hydrolysis. Among these, NAC5 self-assembled into a G-quadruplex structure which has been confirmed by various spectroscopic techniques. The wide-angle powder XRD, ThT dye binding assay and circular dichroism study is carried out to support the presence of the G-quadruplex structure. The biocatalytic formation of nanofibers enclosed spheres is analyzed using CLSM, FE-SEM and HR-TEM experiments. Additionally, we assess the biocompatibility of the enzyme fueled dissipative self-assembled fibers enclosed spheres, as they have potential applications as a biomaterial in protocells. MTT assay is performed to check the cytotoxicity of G-quadruplex hydrogel, using HEK 293 and McCoy cell lines for viability assessment. Finally, the utility of the novel NAC5 hydrogel as a wound repairing biomaterial is demonstrated by cell migration experiment in a scratch assay.

11.
Chemistry ; 30(15): e202304050, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38197477

RESUMO

A low pKa (5.2), high polarizable volume (3.8 Å), and proneness to oxidation under ambient conditions make selenocysteine (Sec, U) a unique, natural reactive handle present in most organisms across all domains of life. Sec modification still has untapped potential for site-selective protein modification and probing. Herein we demonstrate the use of a cyclometalated gold(III) compound, [Au(bnpy)Cl2 ], in the arylation of diselenides of biological significance, with a scope covering small molecule models, peptides, and proteins using a combination of multinuclear NMR (including 77 Se NMR), and LC-MS. Diphenyl diselenide (Ph-Se)2 and selenocystine, (Sec)2 , were used for reaction optimization. This approach allowed us to demonstrate that an excess of diselenide (Au/Se-Se) and an increasing water percentage in the reaction media enhance both the conversion and kinetics of the C-Se coupling reaction, a combination that makes the reaction biocompatible. The C-Se coupling reaction was also shown to happen for the diselenide analogue of the cyclic peptide vasopressin ((Se-Se)-AVP), and the Bos taurus glutathione peroxidase (GPx1) enzyme in ammonium acetate (2 mM, pH=7.0). The reaction mechanism, studied by DFT revealed a redox-based mechanism where the C-Se coupling is enabled by the reductive elimination of the cyclometalated Au(III) species into Au(I).


Assuntos
Cistina/análogos & derivados , Compostos Organosselênicos , Selênio , Animais , Bovinos , Ouro/química , Peptídeos , Glutationa Peroxidase/metabolismo , Selenocisteína/química
12.
Biomed Microdevices ; 26(3): 31, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38951313

RESUMO

Janus particles are popular in recent years due to their anisotropic physical and chemical properties. Even though there are several established synthesis methods for Janus particles, microfluidics-based methods are convenient and reliable due to low reagent consumption, monodispersity of the resultant particles and efficient control over reaction conditions. In this work a simple droplet-based microfluidic technique is utilized to synthesize magnetically anisotropic TiO2-Fe2O3 Janus microparticles. Two droplets containing reagents for Janus particle were merged by using an asymmetric device such that the resulting droplet contained the constituents within its two hemispheres distinct from each other. The synthesized Janus particles were observed under the optical microscope and the scanning electron microscope. Moreover, a detailed in vitro characterization of these particles was completed, and it was shown that these particles have a potential use for biomedical applications.


Assuntos
Materiais Biocompatíveis , Dispositivos Lab-On-A-Chip , Titânio , Titânio/química , Materiais Biocompatíveis/química , Compostos Férricos/química , Desenho de Equipamento , Tamanho da Partícula
13.
Biotechnol Bioeng ; 121(9): 2752-2766, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38877732

RESUMO

Natural hydrogels are widely employed in tissue engineering and have excellent biodegradability and biocompatibility. Unfortunately, the utilization of such hydrogels in the field of three-dimensional (3D) printing nasal cartilage is constrained by their subpar mechanical characteristics. In this study, we provide a multicrosslinked network hybrid ink made of photocurable gelatin, hyaluronic acid, and acrylamide (AM). The ink may be processed into intricate 3D hydrogel structures with good biocompatibility and high stiffness properties using 3D printing technology based on digital light processing (DLP), including intricate shapes resembling noses. By varying the AM content, the mechanical behavior and biocompatibility of the hydrogels can be adjusted. In comparison to the gelatin methacryloyl (GelMA)/hyaluronic acid methacryloyl (HAMA) hydrogel, adding AM considerably enhances the hydrogel's mechanical properties while also enhancing printing quality. Meanwhile, the biocompatibility of the multicrosslinked network hydrogels and the development of cartilage were assessed using neonatal Sprague-Dawley (SD) rat chondrocytes (CChons). Cells sown on the hydrogels considerably multiplied after 7 days of culture and kept up the expression of particular proteins. Together, our findings point to GelMA/HAMA/polyacrylamide (PAM) hydrogel as a potential material for nasal cartilage restoration. The photocuring multicrosslinked network ink composed of appropriate proportions of GelMA/HAMA/PAM is very suitable for DLP 3D printing and will play an important role in the construction of nasal cartilage, ear cartilage, articular cartilage, and other tissues and organs in the future. Notably, previous studies have not explored the application of 3D-printed GelMA/HAMA/PAM hydrogels for nasal cartilage regeneration.


Assuntos
Hidrogéis , Cartilagens Nasais , Impressão Tridimensional , Ratos Sprague-Dawley , Alicerces Teciduais , Animais , Ratos , Hidrogéis/química , Alicerces Teciduais/química , Condrócitos/citologia , Engenharia Tecidual , Ácido Hialurônico/química , Gelatina/química , Bioimpressão/métodos
14.
Arterioscler Thromb Vasc Biol ; 43(6): 797-812, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37078288

RESUMO

Medical devices form a critical component of health care systems for treating and maintaining patient health. However, devices exposed to blood are prone to blood clotting (thrombosis) and bleeding complications leading to device occlusion, device failure, embolism and stroke, and increased morbidity and mortality. Over the years, developments in innovative material design strategies have been made to help reduce the occurrence of thrombotic events on medical devices, but complications persist. Here, we review material and surface coating technologies that have taken bioinspiration from the endothelium to reduce medical device thrombosis, either by mimicking aspects of the glycocalyx to prevent adhesion of proteins and cells to the material surface or mimicking the bioactive function of the endothelium through immobilized or released bioactive molecules to actively inhibit thrombosis. We highlight newer strategies that take inspiration from multiple aspects of the endothelium or are stimuli responsive, only releasing antithrombotic biomolecules when thrombosis is triggered. Emerging areas of innovation target inflammation to decrease thrombosis without increasing bleeding, and interesting results are coming from underexplored aspects of material properties, such as material interfacial mobility and stiffness, which show that increased mobility and decreased stiffness are less thrombogenic. These exciting new strategies require further research and development before clinical translation, including consideration of longevity, cost, and sterilization, but show capacity for the development of more sophisticated antithrombotic medical device materials.


Assuntos
Fibrinolíticos , Trombose , Humanos , Fibrinolíticos/efeitos adversos , Coagulação Sanguínea , Trombose/etiologia , Trombose/prevenção & controle
15.
J Pept Sci ; 30(4): e3551, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37926859

RESUMO

Antibiotic resistance is an escalating global health threat. Due to their diverse mechanisms of action and evasion of traditional resistance mechanisms, peptides hold promise as future antibiotics. Their ability to disrupt bacterial membranes presents a potential strategy to combat drug-resistant infections and address the increasing need for effective antimicrobial treatments. Amphipathic α-helical peptides possess a distinctive molecular structure with both charged/hydrophilic and hydrophobic regions that interact with the bacterial cell membrane, disrupting its structural integrity. The α-helical amphipathic peptide aurein 1.2, secreted by the Australian frog Litoria aurea, is one of the shortest known antimicrobial peptides, spanning only 13 amino acids. The primary objective of this study was to investigate stapled and photoswitchable modifications of short helical peptides employing biocompatible chemistry, utilising aurein 1.2 as a model system. We developed various stapled versions of aurein 1.2 using biocompatible conjugation chemistry between dicyanopyridine and 1,2-aminothiols. While the commonly employed stapling pattern for longer staples is i, i + 7, we observed superior helicity in peptides stapled at positions i, i + 8. Molecular dynamics simulations confirmed both stapling patterns to support an α-helical peptide conformation. Additionally, we utilised a cysteine-selective photosensitive staple, perfluoro azobenzene, to explore photoswitchable variants of aurein 1.2. A double-cysteine variant stapled at i, i + 7 indeed exhibited a change in overall helicity induced by light. We further demonstrated the applicability of this staple to attach to cysteine residues in i, i + 7 positions of a helix in a model protein. While some of the stapled variants displayed substantial increase in helicity, minimal inhibitory concentration assays revealed that none of the stapled aurein 1.2 variants exhibited increased antimicrobial activity compared to the wildtype.


Assuntos
Anti-Infecciosos , Peptídeos Antimicrobianos , Animais , Sequência de Aminoácidos , Cisteína , Conformação Proteica , Austrália , Peptídeos/farmacologia , Peptídeos/química , Anuros , Bactérias
16.
Macromol Rapid Commun ; : e2400345, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38760014

RESUMO

The need for wound closure or surgical procedures has been commonly met by the application of sutures. Unfortunately, these are often invasive or subject to contamination. Alternative solutions are offered by surgical adhesives that can be applied and set without major disruption; a new class of supramolecular-based adhesives provides potential solutions to some of these challenges. In this study, a series of polymers utilizing dopamine as a self-assembling unit are synthesized. It is found that these motifs act as extremely effective adhesives, with control over the mechanical strength of the adhesion and materials' tensile properties enabled by changing monomer feed ratios and levels of cross-linking. These materials significantly outperform commercially available bio-adhesives, showing yield strengths after adhesion at least two times higher than that of BioGlue and Tisseel, as well as the ability to re-adhere with significant recovery of adhesion strength. Promisingly, the materials are shown to be non-cytotoxic, with cell viability > 90%, and able to perform in aqueous environments without significant loss in strength. Finally, the removal of the materials, is possible using benign organic solvents such as ethanol. These properties all demonstrate the effectiveness of the materials as potential bio-adhesives, with potential advantages for use in surgery.

17.
Environ Res ; 260: 119768, 2024 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-39134114

RESUMO

The development of biocompatible adsorbents is vital for environmental remediation to control and reduce pollution and waste accumulation in ecosystems. Biocompatible hydrogels represent an innovative class of materials that are primarily composed of polymer chain units forming their structural framework. They have a high affinity for water molecules. This research thus aims to incorporate iron oxide particles into the gelatin matrix to produce gelatin hydrogel beads to remove hexavalent chromium from an aqueous solution. The synthesized beads, known for their consistent size, low friction, high specific surface area, mechanical stability, and lightweight characteristics, demonstrated their suitability for various industrial applications. The effectiveness of these hydrogels in removing hexavalent chromium ions was confirmed through a thorough analysis using techniques such as FTIR, TGA, SEM, EDX, VSM, and XPS. Batch experiments revealed that the gelatin-based nanocomposite beads exhibited optimal adsorption efficiency under acidic conditions, lower initial concentrations of chromium ions, extended contact time, and elevated temperature (50-60 °C). The composite achieved a maximum removal efficiency of 99% at pH 1, with an adsorbent dose of 0.5 g at 50 °C, and an initial concentration of 50 mg per liter. The use of 0.7 N NaOH in the regeneration process resulted in a commendable 70.5% desorption efficiency, enabling potential reuse and regeneration. Significantly, the desorption efficiency remained consistently high even after four desorption-readsorption cycles, contributing to the economic and environmental sustainability of chromium removal. Additionally, the study determined that the sorption process was feasible, spontaneous, and endothermic. These collective findings suggest that magnetic gelatin hydrogel beads could serve as a cost-effective alternative adsorbent for the efficient removal of chromium ions from aqueous solutions.

18.
Biotechnol Appl Biochem ; 71(3): 596-608, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38298147

RESUMO

The current research article has investigated the synthesis and characterization of novel iron nanoparticles (INPs) from neem and betel leaves extract combination using response surface methodology-central composite design and coated with chitosan-curcumin (CCINPs) as a biocompatible and contrast agent for magnetic resonance imaging (MRI). The coating of INPs with chitosan and curcumin (CCINPs) was carried out using a simple, easy, chemical-free ultrasonication method and characteristics were confirmed by UV-visible (Vis) spectrophotometer (UV-Vis), Fourier-transform infrared spectroscopy, X-ray diffraction, scanning electron microscope, atomic force microscopy, and vibrating sample magnetometer. The biocompatibility of the particles was ensured by conducting hemolytic and cell viability assays. The nanoparticle was found to be nonhemolytic (<5%) up to 150 µg/mL for both INPs and CCINPs. The cell viability was stable (peripheral blood mononuclear cells-PBMCs) till 48 h at 150 µg/mL of INPs and CCINPs. Both the test results produced were found to be biocompatible and additionally, an in vitro MRI study of INPs and CCINPs demonstrated the efficiency of the nanoparticle as a negative contrast agent with enhanced contrast nature in CCINPs. Thus, overall results indicate that the green synthesized chemical-free novel CCINPs could be a potential candidate for a wide range of applications such as MRI, drug delivery, and in magnetic fluid hyperthermia.


Assuntos
Meios de Contraste , Química Verde , Imageamento por Ressonância Magnética , Meios de Contraste/química , Meios de Contraste/síntese química , Meios de Contraste/farmacologia , Humanos , Ferro/química , Curcumina/química , Curcumina/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Nanopartículas Metálicas/química , Extratos Vegetais/química , Quitosana/química
19.
Mikrochim Acta ; 191(9): 514, 2024 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-39105930

RESUMO

A cleanroom free optimized fabrication of a low-cost facile tungsten diselenide (WSe2) combined with chitosan-based hydrogel device is reported for multifunctional applications including tactile sensing, pulse rate monitoring, respiratory rate monitoring, human body movements detection, and human electrophysiological signal detection. Chitosan being a natural biodegradable, non-toxic compound serves as a substrate to the semiconducting WSe2 electrode which is synthesized using a single step hydrothermal technique. Elaborate characterization studies are performed to confirm the morphological, structural, and electrical properties of the fabricated chitosan/WSe2 device. Chitosan/WSe2 sensor with copper contacts on each side is put directly on skin to capture human body motions. The resistivity of the sample was calculated as 26 kΩ m-1. The device behaves as an ultrasensitive pressure sensor for tactile and arterial pulse sensing with response time of 0.9 s and sensitivity of around 0.02 kPa-1. It is also capable for strain sensing with a gauge factor of 54 which is significantly higher than similar other reported electrodes. The human body movements sensing can be attributed to the piezoresistive character of WSe2 that originates from its non-centrosymmetric structure. Further, the sensor is employed for monitoring respiratory rate which measures to 13 counts/min for healthy individual and electrophysiological signals like ECG and EOG which can be used later for detecting numerous pathological conditions in humans. Electrophysiological signal sensing is carried out using a bio-signal amplifier (Bio-Amp EXG Pill) connected to Arduino. The skin-friendly, low toxic WSe2/chitosan dry electrodes pave the way for replacing wet electrodes and find numerous applications in personalized healthcare.


Assuntos
Quitosana , Dispositivos Eletrônicos Vestíveis , Quitosana/química , Humanos , Taxa Respiratória , Selênio/química , Frequência Cardíaca/fisiologia , Movimento , Tungstênio/química , Eletrodos , Monitorização Fisiológica/instrumentação , Monitorização Fisiológica/métodos
20.
Bioprocess Biosyst Eng ; 47(8): 1377-1391, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38819452

RESUMO

The increasing incidence of breast cancer and bacterial biofilm in medical devices significantly heightens global mortality and morbidity, challenging synthetic drugs. Consequently, greener-synthesized nanomaterials have emerged as a versatile alternative for various biomedical applications, offering new therapeutic avenues. This study explores the synthesis of biocompatible zinc oxide (ZnONPs) nanoparticles using Gymnema sylvestre and its antibacterial, antibiofilm, and cytotoxic properties. Characterization of ZnONPs inferred that UV-Vis spectra exhibited a sharp peak at 370 nm. Fourier transform infrared spectroscopical analysis revealed the presence of active functional groups such as aldehyde, alkyne, cyclic alkene, sulfate, alkyl aryl ether, and Zn-O bonds. X-ray diffraction analysis results confirmed the crystalline nature of the nanoparticle. Scanning electron microscope analysis evidenced hexagonal morphology, and energy-dispersive X-ray analysis confirmed zinc content. High-resolution transmission electron microscope analysis showed hexagonal and rod-shaped ZnONPs with a size of 5 nm. Zeta potential results affirmed the stability of nanoparticles. The ZnONPs effectively inhibited gram-positive (18-20 mm) than gram-negative (12-18 mm) bacterial pathogens with lower bacteriostatic and higher bactericidal values. Biofilm inhibitory property inferred ZnONPs were more effective against gram-positive (38-94%) than gram-negative bacteria (27-86%). The concentration of ZnONPs to exert 50% biofilm-inhibitory is lower against gram-positive bacteria (179.26-203.95 µg/mL) than gram-negative bacteria (201.46-236.19 µg/mL). Microscopic visualization inferred that at 250 µg/mL, ZnONPs strongly disrupted biofilm formation, as evidenced by decreased biofilm density and altered architecture. The cytotoxicity of ZnONPs against breast cancer cells showed a dose-dependent reduction in cell viability with an IC50 value of 19.4 µg/mL. AO/EB staining indicated early and late apoptotic cell death of breast cancer cells under fluorescence microscopy. The results of hemolytic activity validated the biocompatibility of the ZnONPs. Thus, the unique properties of the green-synthesized ZnONPs suggest their potential as effective drug carriers for targeted delivery in cancer therapy and the treatment of biofilm-related infections.


Assuntos
Antibacterianos , Biofilmes , Neoplasias da Mama , Gymnema sylvestre , Óxido de Zinco , Humanos , Antibacterianos/farmacologia , Antibacterianos/química , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Óxido de Zinco/química , Óxido de Zinco/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Gymnema sylvestre/química , Feminino , Nanopartículas Metálicas/química , Testes de Sensibilidade Microbiana , Nanopartículas/química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia
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