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1.
Acc Chem Res ; 57(15): 2105-2116, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39056892

RESUMO

ConspectusMetal-organic frameworks (MOFs) are promising for various applications through the creation of innovative materials and assemblies. This potential stems from their modular nature, as diverse metal ions and organic linkers can be combined to produce MOFs with unique chemical properties and lattice structures. Following extensive research on the design and postsynthetic chemical modification of MOF lattices at the molecular level, increasing attention is now focused on the next hierarchical level: controlling the morphology of MOF crystals and their subsequent assembly and positioning to create functional composites.Beyond well-established methods to regulate crystal size and shape through nucleation and coordination modulation, physicochemical techniques leveraging wetting effects, interparticle interactions, and magnetic or electric fields offer attractive avenues for the hierarchical structuring and assembly of MOFs. These techniques facilitate crystal alignment and yield unique superstructures. While our research group primarily focuses on directing MOF crystal orientation and positioning using external stimuli such as magnetic and electric fields, we also explore hierarchical MOF synthesis and structuring using liquid interfaces and depletion force-assisted packing.This account highlights our journey and progress in developing methods to regulate the morphology, assembly, orientation, and positioning of MOF crystals, placed in the context of work by other groups. First, we examine commonly utilized structuring methods for MOF crystals that employ liquid-liquid and air-liquid interfaces to spatially confine reactions, allowing us to access unique morphologies such as mushroom-like crystals and Janus particles. We also discuss strategies for concentrating and packing MOF crystals into superstructures, utilizing fluid interfaces for spatial confinement of crystals, depletion forces, entropic effects, and crystal sedimentation.A particularly compelling challenge in expanding the applicability of MOF materials is how to manipulate free-standing MOF crystals. This issue is especially important because MOFs are typically produced as loose powders, and industrial material processing is generally more efficient when the material is fluidized. While extensive research has been conducted regarding MOF growth on substrates with both positional and orientational control, there is a clear need for similar precision with free-standing MOFs dispersed in a fluid matrix. Our group has thus focused on the relatively new, yet powerful approach of using electric and magnetic fields to manipulate MOF crystals, which offers unprecedented control over the orientation and positioning of dispersed MOF crystals, complementing the more well-established methods of MOF growth on substrates. In this Account, we provide foundational background and discussions on the interactions between these external fields and MOF crystals, including critical considerations for effective MOF manipulation using such techniques. We also discuss their unique advantages and applications, and briefly examine potential application areas, such as photonics, smart materials like soft robotics and absorbents, and sensing. This Account highlights the promising potential of well-organized and aligned MOF crystals over randomly oriented ones in various applications, owing to enhanced selectivity and performance. It underscores the importance of specialized assembly methods to advance materials science and engineering, encouraging the reader to explore such approaches.

2.
Chempluschem ; : e202400210, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38895895

RESUMO

The advancements in the capabilities of artificial sensory technologies, such as electronic/optical noses and tongues, have significantly enhanced their ability to identify complex mixtures of analytes. These improvements are rooted in the evolving manufacturing processes of cross-reactive sensor arrays (CRSAs) and the development of innovative computational methods. The potential applications in early diagnosis, food quality control, environmental monitoring, and more, position CRSAs as an exciting area of research for scientists from diverse backgrounds. Among these, plasmonic CRSAs are particularly noteworthy because they offer enhanced capabilities for remote, fast, and even real-time monitoring, in addition to better portability of instrumentation. Specifically, the synergy between the localized surface plasmon resonance (LSPR) of nanoparticles (NPs) and CRSAs introduces advanced techniques such as surface plasmon resonance (SPR), metal-enhanced fluorescence (MEF), surface-enhanced infrared absorption (SEIRA), surface-enhanced Raman scattering (SERS), and surface-enhanced resonance Raman scattering (SERRS) spectroscopies. This review delves into the importance and versatility of optical-CRSAs, especially those based on plasmonic materials, discussing recent applications and potential new research directions.

3.
Polymers (Basel) ; 16(4)2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38399911

RESUMO

In bone tissue engineering, scaffold attributes such as pore dimensions and mechanical strength are crucial. This study synthesized polycaprolactone dimethacrylate (PCLDMA) from polycaprolactone (PCL), incorporating epichlorohydrin (Epi-PCL) and methacryloyl chloride (Meth-Cl). PCLDMA was blended with polylactic acid (p-PLA) to 3D-print bone scaffolds using stereolithography (SLA). Analytical techniques included nuclear magnetic resonance (NMR), Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and compression testing. Degradation kinetics and cell viability were investigated using human osteoblast (HOB) cells. Findings revealed PCLDMA/p-PLA composite scaffold superiority over the original polymers. Notably, PCLDMA-60 (60% PCLDMA, 40% p-PLA) displayed optimal properties. Compressive strength varied from 0.019 to 16.185 MPa, porosity from 2% to 50%, and degradation rates from 0% to 0.4% over three days. Cell viability assays affirmed biocompatibility across various PCLDMA ratios. In conclusion, PCLDMA/p-PLA composite scaffolds, particularly PCLDMA-60, show great potential in bone tissue engineering.

4.
Curr Top Med Chem ; 24(11): 930-951, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38243934

RESUMO

The field of nanotechnology has witnessed remarkable progress in recent years, particularly in its application to medical diagnosis and therapy. Metallic nanostructures-assisted biosensors have emerged as a powerful and versatile platform, offering unprecedented opportunities for sensitive, specific, and minimally invasive diagnostic techniques, as well as innovative therapeutic interventions. These biosensors exploit the molecular interactions occurring between biomolecules, such as antibodies, enzymes, aptamers, or nucleic acids, and metallic surfaces to induce observable alterations in multiple physical attributes, encompassing electrical, optical, colorimetric, and electrochemical signals. These interactions yield measurable data concerning the existence and concentration of particular biomolecules. The inherent characteristics of metal nanostructures, such as conductivity, plasmon resonance, and catalytic activity, serve to amplify both sensitivity and specificity in these biosensors. This review provides an in-depth exploration of the latest advancements in metallic nanostructures-assisted biosensors, highlighting their transformative impact on medical science and envisioning their potential in shaping the future of personalized healthcare.


Assuntos
Técnicas Biossensoriais , Nanoestruturas , Humanos , Nanoestruturas/química , Metais/química , Nanopartículas Metálicas/química
5.
Chemistry ; 30(24): e202303987, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38294096

RESUMO

Surface-enhanced Raman scattering (SERS) spectroscopy, a highly sensitive technique for detecting trace-level analytes, relies on plasmonic substrates. The choice of substrate, its morphology, and the excitation wavelength are crucial in SERS applications. To address advanced SERS requirements, the design and use of efficient nanocomposite substrates have become increasingly important. Notably, magnetic-plasmonic (MP) nanocomposites, which combine magnetic and plasmonic properties within a single particle system, stand out as promising nanoarchitectures with versatile applications in nanomedicine and SERS spectroscopy. In this review, we present an overview of MP nanocomposite fabrication methods, explore surface functionalization strategies, and evaluate their use in SERS. Our focus is on how different nanocomposite designs, magnetic and plasmonic properties, and surface modifications can significantly influence their SERS-related characteristics, thereby affecting their performance in specific applications such as separation, environmental monitoring, and biological applications. Reviewing recent studies highlights the multifaceted nature of these materials, which have great potential to transform SERS applications across a range of fields, from medical diagnostics to environmental monitoring. Finally, we discuss the prospects of MP nanocomposites, anticipating favorable developments that will make substantial contributions to various scientific and technological areas.

6.
ACS Nanosci Au ; 3(3): 222-229, 2023 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-37360844

RESUMO

Herein, we designed and synthesized a hybrid material comprising polystyrene submicrobeads coated with silver nanospheres. This material provides a dense collection of electromagnetic hot spots upon illumination with visible light. The subsequent coating with a metal-framework and the adsorption of bathocuproine on it yield an optical sensor for SERS that can specifically detect Cu(II) in a variety of aqueous samples at the ultratrace level. Detection limits with this method are superior to those of induced coupled plasma or atomic absorption and comparable with those obtained with induced coupled plasma coupled with a mass detector.

7.
Angew Chem Int Ed Engl ; 62(26): e202305299, 2023 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-37186430

RESUMO

Hybrid composites between nanoparticles and metal organic frameworks (MOFs) have been described as optimal materials for a wide range of applications in optical sensing, drug delivery, pollutant removal or catalysis. These materials are usually core-shell single- or multi-nanoparticles, restricting the inorganic surface available for reaction. Here, we develop a method for the preparation of yolk-shells consisting in a plasmonic gold nanostar coated with MOF. This configuration shows more colloidal stability, can sieve different molecules based on their size or charge, seems to show some interesting synergy with gold for their application in photocatalysis and present strong optical activity to be used as SERS sensors.


Assuntos
Estruturas Metalorgânicas , Nanopartículas , Ouro , Sistemas de Liberação de Medicamentos , Catálise
8.
J Chem Phys ; 158(17)2023 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-37125707

RESUMO

In recent years, metal-organic frameworks, in general, and zeolitic imidazolate frameworks, in special, had become popular due to their large surface area, pore homogeneity, and easy preparation and integration with plasmonic nanoparticles to produce optical sensors. Herein, we summarize the late advances in the use of these hybrid composites in the field of surface-enhanced Raman scattering and their future perspectives.

9.
Daru ; 28(1): 139-157, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31942695

RESUMO

BACKGROUND: Arginine-vasopressin (AVP) is a neuropeptide and provides learning and memory modulation. The AVP (4-5) dipeptide corresponds to the N-terminal fragment of the major vasopressin metabolite AVP (4-9), has a neuroprotective effect and used in the treatment of Alzheimer's and Parkinson's disease. METHODS: The main objective of the present study is to evaluate the molecular mechanism of AVP (4-5) dipeptide and to develop and synthesize chitosan nanoparticle formulation using modified version of ionic gelation method, to increase drug effectiveness. For peptide loaded chitosan nanoparticles, the synthesized experiment medium was simulated for the first time by molecular dynamics method and used to determine the stability of the peptide, and the binding mechanism to protein (HSP70) was also investigated by molecular docking calculations. A potential pharmacologically features of the peptide was also characterized by ADME (Absorption, Distribution, Metabolism and Excretion) analysis. The characterization, in vitro release study, encapsulation efficiency and loading capacity of the peptide loaded chitosan nanoparticles (CS NPs) were performed by Dynamic Light Scattering (DLS), UV-vis absorption (UV), Scanning Electron Microscopy (SEM), Fourier transform infrared (FT-IR) spectroscopy techniques. Additionally, in vitro cytotoxicity of the peptide on human neuroblastoma cells (SH-SY5Y) was examined with XTT assay and the statistical analysis was evaluated. RESULTS: The results showed that; hydrodynamic size, zeta potential and polydispersity index (PdI) of the peptide-loaded CS NPs were 167.6 nm, +13.2 mV, and 0.211, respectively. In vitro release study of the peptide-loaded CS NPs showed that 17.23% of the AVP (4-5)-NH2 peptide was released in the first day, while 61.13% of AVP (4-5)-NH2 peptide was released in the end of the 10th day. The encapsulation efficiency and loading capacity were 99% and 10%, respectively. According to the obtained results from XTT assay, toxicity on SHSY-5Y cells in the concentration from 0.01 µg/µL to 30 µg/µL were evaluated and no toxicity was observed. Also, neuroprotective effect was showed against H2O2 treatment. CONCLUSION: The experimental medium of peptide-loaded chitosan nanoparticles was created for the first time with in silico system and the stability of the peptide in this medium was carried out by molecular dynamics studies. The binding sites of the peptide with the HSP70 protein were determined by molecular docking analysis. The size and morphology of the prepared NPs capable of crossing the blood-brain barrier (BBB) were monitored using DLS and SEM analyses, and the encapsulation efficiency and loading capacity were successfully performed with UV Analysis. In vitro release studies and in vitro cytotoxicity analysis on SHSY-5Y cell lines of the peptide were conducted for the first time. Grapical abstract.


Assuntos
Arginina Vasopressina , Quitosana , Nanopartículas , Fármacos Neuroprotetores , Peptídeos , Arginina Vasopressina/administração & dosagem , Arginina Vasopressina/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Quitosana/administração & dosagem , Quitosana/química , Desenho de Fármacos , Humanos , Peróxido de Hidrogênio/toxicidade , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Nanopartículas/administração & dosagem , Nanopartículas/química , Fármacos Neuroprotetores/administração & dosagem , Fármacos Neuroprotetores/química , Peptídeos/administração & dosagem , Peptídeos/química
10.
Curr Comput Aided Drug Des ; 16(2): 104-121, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31244443

RESUMO

BACKGROUND: Sulpiride, which has selective dopaminergic blocking activity, is a substituted benzamide antipsychotic drug playing a prominent role in the treatment of schizophrenia, which more selective and primarily blocks dopamine D2 and D3 receptor. OBJECTIVE: This study has two main objectives, firstly; the molecular modeling studies (MD and Docking, ADME) were conducted to define the molecular profile of sulpiride and sulpiridereceptor interactions, another to synthesize polymeric nanoparticles with chitosan, having the advantage of slow/controlled drug release, to improve drug solubility and stability, to enhance utility and reduce toxicity. METHODS: Molecular dynamic simulation was carried out to determine the conformational change and stability (in water) of the drug and the binding profile of D3 dopamine receptor was determined by molecular docking calculations. The pharmacological properties of the drug were revealed by ADME analysis. The ionic gelation method was used to prepare sulpiride loaded chitosan nanoparticles (CS NPs). The Dynamic Light Scattering (DLS), UV-vis absorption (UV), Scanning Electron Microscopy (SEM), Fourier transform infrared (FT-IR) spectroscopy techniques were carried out to characterize the nanoparticles. In vitro cell cytotoxicity experiments examined with MTT assay on mouse fibroblast (L929), human neuroblastoma (SH-SY5Y) and glioblastoma cells (U-87). The statistical evaluations were produced by ANOVA. RESULTS: The residues (ASP-119, PHE-417) of D3 receptor provided a stable docking with the drug, and the important pharmacological values (blood brain barrier, Caco-2 permeability and human oral absorption) were also determined. The average particle size, PdI and zeta potential value of sulpiride- loaded chitosan NPs having a spherical morphology were calculated as 96.93 nm, 0.202 and +7.91 mV. The NPs with 92.8% encapsulation and 28% loading efficiency were found as a slow release profile with 38.49% at the end of the 10th day. Due to the formation of encapsulation, the prominent shifted wave numbers for C-O, S-O, S-N stretching, S-N-H bending of Sulpiride were also identified. Mitochondrial activity of U87, SHSY-5Y and L929 cell line were assayed and evaluated using the SPSS program. CONCLUSION: To provide more efficient use of Sulpiride having a low bioavailability of the gastrointestinal tract, the nanoparticle formulation with high solubility and bioavailability was designed and synthesized for the first time in this study for the treatment of schizophrenia. In addition to all pharmacological properties of drug, the dopamine blocking activity was also revealed. The toxic effect on different cell lines have also been interpreted.


Assuntos
Simulação de Acoplamento Molecular , Nanopartículas/química , Sulpirida/química , Sulpirida/síntese química , Animais , Disponibilidade Biológica , Células CACO-2 , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Quitosana , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Humanos , Camundongos , Tamanho da Partícula , Esquizofrenia , Solubilidade , Sulpirida/administração & dosagem
11.
J Fluoresc ; 28(5): 1127-1142, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30097974

RESUMO

Papain is a protease enzyme with therapeutic properties that are very valuable for medical applications. Poly(ε-caprolactone) (PCL) is an ideal polymeric carrier for controlled drug delivery systems due to its low biodegradability and its high biocompatibility. In this study, the three-dimensional structure and action mechanism of papain were investigated by in vitro and in silico experiments using molecular dynamics (MD) and molecular docking methods to elucidate biological functions. The results showed that the size of papain-loaded PCL nanoparticles (NPs) and the polydispersity index (PDI) of the NPs were 242.9 nm and 0.074, respectively. The encapsulation efficiency and loading efficiency were 80.4 and 27.2%, respectively. Human embryonic kidney cells (HEK-293) were used for determining the cytotoxicity of papain-loaded PCL and PCL nanoparticles. The in vitro cell culture showed that nanoparticles are not toxic at low concentrations, while toxicity slightly increases at high concentrations. In silico studies, which were carried out with MD simulations and ADME analysis showed that the strong hydrogen bonds between the ligand and the papain provide stability and indicate the regions in which the interactions occur.


Assuntos
Simulação por Computador , Portadores de Fármacos/química , Nanopartículas , Papaína/química , Poliésteres/química , Transporte Biológico , Sobrevivência Celular/efeitos dos fármacos , Portadores de Fármacos/metabolismo , Portadores de Fármacos/toxicidade , Liberação Controlada de Fármacos , Células HEK293 , Humanos , Teste de Materiais , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Papaína/metabolismo , Poliésteres/metabolismo , Poliésteres/toxicidade , Conformação Proteica
13.
Environ Toxicol ; 28(11): 644-51, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21913301

RESUMO

Esbiothrin, synthetic pyrethroid with quick activity against insects, is widely used against household pests and in public health. Despite widespread use, data on ecotoxicity and genotoxic effects are extremely scarce. The aim of the present study is to evaluate the genotoxic potential of esbiothrin on a model fish species Cyprinus carpio L., 1758 (Pisces: Cyprinidae, koi) using the micronucleus test and comet assay in peripheral blood erythrocytes. Effects of two sublethal exposure concentrations on plasma total antioxidant status (TAS mmol/L), and Hct values were examined. On the basis of the 96 h LC50 data from U.S. EPA ecotox database (32 µg/L) two sublethal exposure concentrations (5 and 10 µg/L) were used together with ethyl methanesulfonate (EMS) (5 mg/L) as positive control. Five fish were used for each dose/duration group (24, 48, and 72 h) under controlled laboratory conditions. The fish showed behavioral changes at the higher dose. Plasma TAS (mmol/L) levels decreased in 24 h; an increase was observed slightly for 48 and obviously for 72 h in both exposure doses. Similarly, hematocrit (Hct) values differed between exposure duration but no significant differences in mean values were found between groups of the same exposure time. The general trend was a rise after 48 h, which decreased afterwards. Our results revealed significant increases in the frequencies of micronuclei and levels of DNA strand breaks and thus demonstrated the genotoxic potential of this pesticide on fish, a nontarget organism of the aquatic ecosystem. To our knowledge this is the first study to report observable genotoxic effects of esbiothrin on fish.


Assuntos
Aletrinas/análogos & derivados , Antioxidantes/metabolismo , Carpas/metabolismo , Inseticidas/toxicidade , Aletrinas/toxicidade , Animais , Carpas/genética , Ensaio Cometa , Dano ao DNA/efeitos dos fármacos , Eritrócitos/efeitos dos fármacos , Testes para Micronúcleos
14.
Food Chem Toxicol ; 53: 359-63, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23266271

RESUMO

The present study was designed to determine the radioprotective effect of two phytochemicals, namely, quinic acid and chlorogenic acid, against X-ray irradiation-induced genomic instability in non-tumorigenic human blood lymphocytes. The protective ability of two phenolic acids against radiation-induced DNA damage was assessed using the alkaline comet assay in human blood lymphocytes isolated from two healthy human donors. A Siemens Mevatron MD2 (Siemens AG, USA, 1994) linear accelerator was used for irradiation. The results of the alkaline comet assay revealed that quinic acid and chlorogenic acid decreased the DNA damage induced by X-ray irradiation and provided a significant radioprotective effect. Quinic acid decreased the presence of irradiation-induced DNA damage by 5.99-53.57% and chlorogenic acid by 4.49-48.15%, as determined by the alkaline comet assay. The results show that quinic acid and chlorogenic acid may act as radioprotective compounds. Future studies should focus on determining the mechanism by which these phenolic acids provide radioprotection.


Assuntos
Ácido Clorogênico/farmacologia , Dano ao DNA/efeitos dos fármacos , Ácido Quínico/farmacologia , Protetores contra Radiação/farmacologia , Raios X/efeitos adversos , Adulto , Ensaio Cometa , Relação Dose-Resposta a Droga , Relação Dose-Resposta à Radiação , Feminino , Humanos , Linfócitos/efeitos dos fármacos , Linfócitos/efeitos da radiação , Masculino , Adulto Jovem
15.
Food Chem Toxicol ; 48(8-9): 2443-7, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20538035

RESUMO

In the present study, the in vivo micronucleus (MN) test in fish erythrocytes was used to evaluate the genotoxic potentials of water samples collected from four different sites along the Nilufer Stream which empties into the Marmara Sea on the north-west of Turkey. Nilufer Stream receives discharges of industrial and domestic wastes resulting from industrialization and urbanization activities in Bursa city. Nile tilapias (Oreochromis niloticus) were exposed to collected water samples under laboratory conditions for 3 and 6 days. Micronuclei analyses were carried out in peripheral blood erythrocytes. In addition to micronuclei, other nuclear abnormalities (NAs) such as bi-nucleated cells and binuclei with nucleoplasmic bridge and cells with blebbed, notched and lobbed nuclei, were assessed in the erythrocytes. Chemical analyses were also carried out in the water samples to assess the presence of major pollutants. MN and NA frequencies were significantly elevated in fishes exposed to water from polluted areas compared to those exposed to clean water sample. The results of this study indicate that Nilufer Stream is contaminated with potential genotoxic chemicals and the genotoxicity is possibly related with the industrial, agricultural and domestic activities.


Assuntos
Ciclídeos/genética , Mutagênicos/toxicidade , Abastecimento de Água/análise , Animais , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/ultraestrutura , Monitoramento Ambiental , Eritrócitos/efeitos dos fármacos , Eritrócitos/ultraestrutura , Concentração de Íons de Hidrogênio , Metais Pesados/análise , Metais Pesados/toxicidade , Testes para Micronúcleos , Oxigênio/análise , Turquia , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
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