Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 407
Filtrar
1.
Eur J Med Chem ; 275: 116603, 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-38936150

RESUMEN

Metal ions carry out a wide variety of functions, including acid-base/redox catalysis, structural functions, signaling, and electron transport. Understanding the interactions of transition metal complexes with biomacromolecules is essential for biology, medicinal chemistry, and the production of synthetic metalloenzymes. After the coincidental discovery of cisplatin, importance of the metal complexes in biochemistry became a top priority for inquiry. In this review, a decade update on various synthetic strategies to first row transition metal complex and their interaction with DNA through non-covalent binding are explored. Moreover, this effort provides an excellent analysis on the efficacy of theoretical and practical approaches to the systematic generation of new non-platinum based metallodrugs for anti-cancer therapeutics.


Asunto(s)
Antineoplásicos , Complejos de Coordinación , ADN , Elementos de Transición , Antineoplásicos/química , Antineoplásicos/farmacología , Antineoplásicos/síntesis química , Humanos , Elementos de Transición/química , Complejos de Coordinación/química , Complejos de Coordinación/farmacología , Complejos de Coordinación/síntesis química , ADN/química , ADN/metabolismo , Animales , Estructura Molecular , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Sitios de Unión/efectos de los fármacos
2.
Dalton Trans ; 53(23): 9612-9656, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38808485

RESUMEN

Carbon monoxide, the "silent killer" gas, is increasingly recognised as an important signalling molecule in human physiology, which has beneficial biological properties. A particular way of achieving controlled CO administration is based on the use of biocompatible molecules that only release CO when triggered by internal or external factors. These approaches include the development of pharmacologically effective prodrugs known as CO releasing molecules (CORMs), which can supply biological systems with CO in well-regulated doses. An overview of transition metal-based CORMs with cytotoxic properties is here reported. The mechanisms at the basis of the biological activities of these molecules and their potential therapeutical applications with respect to their stability and CO releasing properties have been discussed. The activation of metal-based CORMs is determined by the type of metal and by the nature and features of the auxiliary ligands, which affect the metal core electronic density and therefore the prodrug resistance towards oxidation and CO release ability. A major role in regulating the cytotoxic properties of these CORMs is played by CO and/or CO-depleted species. However, several mysteries concerning the cytotoxicity of CORMs remain as intriguing questions for scientists.


Asunto(s)
Monóxido de Carbono , Profármacos , Monóxido de Carbono/química , Monóxido de Carbono/farmacología , Humanos , Profármacos/química , Profármacos/farmacología , Animales , Complejos de Coordinación/química , Complejos de Coordinación/farmacología , Complejos de Coordinación/síntesis química , Antineoplásicos/farmacología , Antineoplásicos/química , Elementos de Transición/química
3.
Eur J Med Chem ; 274: 116528, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-38805938

RESUMEN

Herein, we present a comprehensive review focusing on synthetic strategies, detailed structural analysis, and anticancer activity investigations of complexes following the general formula [LnM(µ-diphosphine)M'Lm] where M = group 8 metal; M' = any transition metal; µ-diphosphine = bridging ligand; Ln and Lm = ligand spheres). Both homo- and heteromultimetallic complexes will be discussed in detail. We review in vitro, in vivo and in silico anticancer activity investigations, in an attempt to draw comparisons between the various complexes and derive structure-activity relationships (SAR). This review solely focuses on complexes falling under the general formula stated above that have been studied for their anticancer activities, other complexes falling into that scheme but which have not undergone anticancer testing are not included in this review. We compare the anticancer activities of these complexes to their mononuclear counterparts, and a positive control (cisplatin) when possible and present a summary of all existing data to date and attempt to draw some conclusions on the future development of these complexes.


Asunto(s)
Antineoplásicos , Complejos de Coordinación , Fosfinas , Elementos de Transición , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/síntesis química , Humanos , Ligandos , Fosfinas/química , Fosfinas/farmacología , Complejos de Coordinación/química , Complejos de Coordinación/farmacología , Complejos de Coordinación/síntesis química , Elementos de Transición/química , Elementos de Transición/farmacología , Relación Estructura-Actividad , Ensayos de Selección de Medicamentos Antitumorales , Estructura Molecular , Animales , Proliferación Celular/efectos de los fármacos
4.
ACS Nano ; 18(19): 12049-12095, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38693611

RESUMEN

Cancer, as one of the leading causes of death worldwide, drives the advancement of cutting-edge technologies for cancer treatment. Transition-metal-based nanozymes emerge as promising therapeutic nanodrugs that provide a reference for cancer therapy. In this review, we present recent breakthrough nanozymes for cancer treatment. First, we comprehensively outline the preparation strategies involved in creating transition-metal-based nanozymes, including hydrothermal method, solvothermal method, chemical reduction method, biomimetic mineralization method, and sol-gel method. Subsequently, we elucidate the catalytic mechanisms (catalase (CAT)-like activities), peroxidase (POD)-like activities), oxidase (OXD)-like activities) and superoxide dismutase (SOD)-like activities) of transition-metal-based nanozymes along with their activity regulation strategies such as morphology control, size manipulation, modulation, composition adjustment and surface modification under environmental stimulation. Furthermore, we elaborate on the diverse applications of transition-metal-based nanozymes in anticancer therapies encompassing radiotherapy (RT), chemodynamic therapy (CDT), photodynamic therapy (PDT), photothermal therapy (PTT), sonodynamic therapy (SDT), immunotherapy, and synergistic therapy. Finally, the challenges faced by transition-metal-based nanozymes are discussed alongside future research directions. The purpose of this review is to offer scientific guidance that will enhance the clinical applications of nanozymes based on transition metals.


Asunto(s)
Antineoplásicos , Neoplasias , Elementos de Transición , Humanos , Neoplasias/tratamiento farmacológico , Neoplasias/terapia , Neoplasias/patología , Elementos de Transición/química , Antineoplásicos/química , Antineoplásicos/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/uso terapéutico , Fotoquimioterapia , Nanoestructuras/química , Animales
5.
Luminescence ; 39(5): e4770, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38751216

RESUMEN

The ultimate goal of nanoparticle-based phototherapy is to suppress tumor growth. Photothermal therapy (PTT) and photothermal photodynamic therapy (PDT) are two types of physicochemical therapy that use light radiation with multiple wavelength ranges in the near-infrared to treat cancer. When a laser is pointed at tissue, photons are taken in the intercellular and intracellular regions, converting photon energy to heat. It has attracted much interest and research in recent years. The advent of transition materials dichalcogenides (TMDCs) is a revolutionary step in PDT/PTT-based cancer therapy. The TMDCs is a multilayer 2D nano-composite. TMDCs contain three atomic layers in which two chalcogens squash in the transition metal. The chalcogen atoms are highly reactive, and the surface characteristics of TMDCs help them to target deep cancer cells. They absorb Near Infrared (NIR), which kills deep cancer cells. In this review, we have discussed the history and mechanism of PDT/PTT and the use of TMDCs and nanoparticle-based systems, which have been practiced for theranostics purposes. We have also discussed PDT/PTT combined with immunotherapy, in which the cancer cell apoptosis is done by activating the immune cells, such as CD8+.


Asunto(s)
Neoplasias , Fotoquimioterapia , Terapia Fototérmica , Elementos de Transición , Humanos , Neoplasias/tratamiento farmacológico , Neoplasias/terapia , Neoplasias/patología , Elementos de Transición/química , Elementos de Transición/farmacología , Calcógenos/química , Calcógenos/farmacología , Fármacos Fotosensibilizantes/química , Fármacos Fotosensibilizantes/farmacología , Animales
6.
Luminescence ; 39(5): e4771, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38747206

RESUMEN

The second-most common cause of death resulting from genetic mutations in DNA sequences is cancer. The difficulty in the field of anticancer research is the application of the traditional methods, which also affects normal cells. Mutations, genetic replication alterations, and chromosomal abnormalities have a direct impact on the effectiveness of anticancer drugs at different stages. Presently, therapeutic techniques utilize nanotechnology, transition metal dichalcogenides (TMDCs), and robotics. TMDCs are being increasingly employed in tumor therapy and biosensing applications due to their biocompatibility, adjustable bandgap, versatile functionality, exceptional photoelectric properties, and wide range of applications. This study reports the advancement of nanoplatforms based on TMDCs that are specifically engineered for responsive and intelligent cancer therapy. This article offers a thorough examination of the current challenges, future possibilities for theranostic applications using TMDCs, and recent progress in employing TMDCs for cancer therapy. Currently, there is significant interest in two-dimensional (2D) TMDCs nanomaterials as ultrathin unique physicochemical properties. These materials have attracted attention in various fields, including biomedicine. Due to their inherent ability to absorb near-infrared light and their exceptionally large surface area, significant efforts are being made to prepare multifunctional nanoplatforms based on 2D TMDCs.


Asunto(s)
Calcógenos , Neoplasias , Elementos de Transición , Humanos , Neoplasias/tratamiento farmacológico , Elementos de Transición/química , Calcógenos/química , Antineoplásicos/química , Antineoplásicos/farmacología , Animales
7.
Biomater Sci ; 12(12): 3154-3162, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38687170

RESUMEN

The effectiveness of photodynamic therapy (PDT) has been greatly restricted by the hypoxic tumor microenvironment and the susceptible resistance of monotherapy. Although nanodrugs based on transition metal complexes capable of integrating PDT with photoactivated chemotherapy (PACT) have garnered tremendous attention as promising candidates for overcoming the above limitations, the therapeutic efficacy of these nanodrugs is still hampered by inadequate loading of active pharmaceutical ingredients (APIs) and the inherent ability of cancer cells to repair damaged DNA. Herein, we developed a photoactivated full-API nanodrug, Ru-T FAND, by one-step self-assembly of RuDPB and TH287. By virtue of its 100 wt% API content and favorable stability in water, the Ru-T FAND exhibited improved cellular uptake behavior and intracellular 1O2 generation. Attractively, the Ru-T FAND with triple anti-cancer modalities can photogenerate 1O2, photo-release DPB ligand and inhibit the repair of DNA damage, ultimately enhancing its phototherapeutic effect on cancer cells. Importantly, the uncaged DPB ligand from RuDPB emits red fluorescence, enabling real-time monitoring of the drug's absorption, distribution and efficacy. Collectively, the presented photoactivated Ru-T FANDs with multiple anti-cancer mechanisms will expand new horizons for the development of safe, efficient and synergistic tumor phototherapy strategies.


Asunto(s)
Antineoplásicos , Complejos de Coordinación , Daño del ADN , Fotoquimioterapia , Humanos , Daño del ADN/efectos de los fármacos , Complejos de Coordinación/farmacología , Complejos de Coordinación/química , Antineoplásicos/farmacología , Antineoplásicos/química , Monoéster Fosfórico Hidrolasas/antagonistas & inhibidores , Monoéster Fosfórico Hidrolasas/metabolismo , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/química , Línea Celular Tumoral , Nanopartículas/química , Rutenio/química , Rutenio/farmacología , Elementos de Transición/química , Elementos de Transición/farmacología , Enzimas Reparadoras del ADN/antagonistas & inhibidores , Enzimas Reparadoras del ADN/metabolismo
8.
J Phys Chem Lett ; 15(14): 3900-3906, 2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38564363

RESUMEN

Nanopores with two-dimensional materials have various advantages in sensing, but the fast translocation of molecules hinders their scale-up applications. In this work, we investigate the influence of -F, -O, and -OH surface terminations on the translocation of peptides through MXene nanopores. We find that the longest dwell time always occurs when peptides pass through the Ti3C2O2 nanopores. This elongated dwell time is induced by the strongest interaction between peptides and the Ti3C2O2 membrane, in which the van der Waals interactions dominate. Compared to the other two MXene nanopores, the braking effect is indicated during the whole translocation process, which evidence the advantage of Ti3C2O2 in nanopore sensing. Our work demonstrates that membrane surface chemistry has a great influence on the translocation of peptides, which can be introduced in the design of nanopores for a better performance.


Asunto(s)
Nanoporos , Nitritos , Elementos de Transición , Péptidos
9.
ACS Appl Mater Interfaces ; 16(14): 17208-17218, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38530974

RESUMEN

Bone defects are common with increasing high-energy fractures, tumor bone invasion, and implantation revision surgery. Bone is an electroactive tissue that has electromechanical interaction with collogen, osteoblasts, and osteoclasts. Hydrogel provides morphological plasticity and extracellular matrix (ECM) 3D structures for cell survival, and is widely used as a bone engineering material. However, the hydrogels have poor mechanical intensity and lack of cell adhesion, slow gelation time, and limited conductivity. MXenes are novel nanomaterials with hydrophilic groups that sense cell electrophysiology and improve hydrogel electric conductivity. Herein, gelatin had multiple active groups (NH2, OH, and COOH) and an accelerated gelation time. Acrylamide has Schiff base bonds to cross-link with gelatin and absorb metal ions. Deacetylated chitosan improved cell adhesion and active groups to connect MXene and acrylamide. We constructed Mo2Ti2C3 MXene hydrogel with improved elastic modulus and viscosity, chemical cross-linking structure, electric conductivity, and good compatibility. Mo2Ti2C3 MXene hydrogel exhibits outstanding osteogenesis in vitro. Mo2Ti2C3 MXene hydrogel promotes osteogenesis via alkaline phosphatase (ALP) and alizarin red S (ARS) staining, improving osteogenic marker genes and protein expressions in vitro. Mo2Ti2C3 MXene hydrogel aids new bone formation in the in vivo calvarial bone defect model via micro-CT and histology. Mo2Ti2C3 MXene hydrogel facilitates neurogenesis factors nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) expression, and aids newly born neuron marker Tuj-1 and sensory neuron marker serotonin (5-HT) and osteogenesis pathway proteins, runt-related transcription factor 2 (Runx2), osteocalcin (OCN), SMAD family member 4 (SMAD4), and bone morphogenetic protein-2 (BMP2) in the bone defect repair process. Mo2Ti2C3 MXene hydrogel promotes osteogenesis and neurogenesis, which extends its biomedical application in bone defect reconstruction.


Asunto(s)
Hidrogeles , Nitritos , Titanio , Elementos de Transición , Hidrogeles/farmacología , Hidrogeles/química , Gelatina , Regeneración Ósea , Osteogénesis , Neurogénesis , Acrilamidas , Diferenciación Celular
10.
Int J Biol Macromol ; 265(Pt 2): 130957, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38499121

RESUMEN

Deterioration in mechanical performances and aging resistance due to the introduction of flame retardants is a major obstacle for bio-based fire-safety polypropylene (PP). Herein, we reported a kind of functionalized lignin nanoparticles assembled with MXene (MX@LNP), and applied it to construct the flame-retardant PP composites (PP-MA) with superior fire safety, excellent mechanical performance, electromagnetic shielding effects and aging resistance. Specifically, the PP-MA doped with only 18 wt% flame-retardant additives (PP-MA18) achieved the UL-94 V-0 rating. In comparison to pure PP, PP-MA18 presented a greatly decreased peak of heat release rate (pHRR), total heat rate (THR), and peak smoke production rate (pSPR) by 79.7 %, 69.0 % and 75.8 %, respectively, and satisfactory decrease in total flammable and toxic volatiles evolved. The formed fine solid microstructure of carbon residuals effectively promoted the compactness of char layers. More importantly, the nano-effect and the strong interface interaction between the complexed MX@LNP and PP enhanced the tensile strength (45.78 MPa) and elongation at break (725.95 %) of PP-MA. Additionally, the significant ultraviolet absorption and electromagnetic wave dissipation performance of MXene and lignin enabled excellent aging resistance and electromagnetic shielding effects of PP-MA compared with PP. This achieved MX@LNP afforded a novel approach for developing flame retardant materials with excellent application performance.


Asunto(s)
Retardadores de Llama , Nanopartículas , Nitritos , Elementos de Transición , Lignina , Polipropilenos , Fenómenos Electromagnéticos
11.
Biomaterials ; 307: 122523, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38432004

RESUMEN

Anticancer nanomedicines used for ferroptosis therapy generally rely on the direct delivery of Fenton catalysts to drive lipid peroxidation in cancer cells. However, the therapeutic efficacy is limited by the ferroptosis resistance caused by the intracellular anti-ferroptotic signals. Herein, we report the intrinsic ATPase-mimicking activity of a vanadium carbide MXene nanozyme (PVCMs) to pharmacologically modulate the nuclear factor erythroid 2-related factor 2 (Nrf2) program, which is the master anti-ferroptotic mediator in the ironclad defense system in triple-negative breast cancer (TNBC) cells. The PVCMs perform high ATPase-like activity that can effectively and selectively catalyze the dephosphorylation of ATP to generate ADP. Through a cascade mechanism initiated by falling energy status, PVCMs can powerfully hinder the Nrf2 program to selectively drive ferroptosis in TNBC cells in response to PVCMs-induced glutathione depletion. This study provides a paradigm for the use of pharmacologically active nanozymes to moderate specific cellular signals and elicit desirable pharmacological activities for therapeutic applications.


Asunto(s)
Ferroptosis , Nitritos , Elementos de Transición , Neoplasias de la Mama Triple Negativas , Humanos , Adenosina Trifosfatasas , Factor 2 Relacionado con NF-E2 , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico
12.
J Colloid Interface Sci ; 665: 389-398, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38537587

RESUMEN

Photothermal therapy (PTT) has attracted much attention due to its less invasive, controllable and highly effective nature. However, PTT also suffers from intrinsic cancer resistance mediated by cell survival pathways. These survival pathways are regulated by a variety of proteins, among which heat shock protein (HSP) triggers thermotolerance and protects tumor cells from hyperthermia-induced apoptosis. Confronted by this challenge, we propose and validate here a novel MXene-based HSP-inhibited mild photothermal platform, which significantly enhances the sensitivity of tumor cells to heat-induced stress and thus improves the PPT efficacy. The Ti3C2@Qu nanocomposites are constructed by utilizing the high photothermal conversion ability of Ti3C2 nanosheets in combination with quercetin (Qu) as an inhibitor of HSP70. Qu molecules are loaded onto the nanoplatform in a pH-sensitive controlled release manner. The acidic environment of the tumor causes the burst-release of Qu molecules, which deplete the level of heat shock protein 70 (HSP70) in tumor cells and leave the tumor cells out from the protection of the heat-resistant survival pathway in advance, thus sensitizing the hyperthermia efficacy. The nanostructure, photothermal properties, pH-responsive controlled release, synergistic photothermal ablation of tumor cells in vitro and in vivo, and hyperthermia effect on subcellular structures of the Ti3C2@Qu nanocomposites were systematically investigated.


Asunto(s)
Hipertermia Inducida , Nanocompuestos , Nanopartículas , Neoplasias , Nitritos , Elementos de Transición , Humanos , Preparaciones de Acción Retardada , Titanio/farmacología , Fototerapia , Neoplasias/terapia , Línea Celular Tumoral , Nanopartículas/química
13.
J Nanobiotechnology ; 22(1): 111, 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38486273

RESUMEN

Brain damage is a common tissue damage caused by trauma or diseases, which can be life-threatening. Stem cell implantation is an emerging strategy treating brain damage. The stem cell is commonly embedded in a matrix material for implantation, which protects stem cell and induces cell differentiation. Cell differentiation induction by this material is decisive in the effectiveness of this treatment strategy. In this work, we present an injectable fibroin/MXene conductive hydrogel as stem cell carrier, which further enables in-vivo electrical stimulation upon stem cells implanted into damaged brain tissue. Cell differentiation characterization of stem cell showed high effectiveness of electrical stimulation in this system, which is comparable to pure conductive membrane. Axon growth density of the newly differentiated neurons increased by 290% and axon length by 320%. In addition, unfavored astrocyte differentiation is minimized. The therapeutic effect of this system is proved through traumatic brain injury model on rats. Combined with in vivo electrical stimulation, cavities formation is reduced after traumatic brain injury, and rat motor function recovery is significantly promoted.


Asunto(s)
Bombyx , Lesiones Traumáticas del Encéfalo , Fibroínas , Células Madre Mesenquimatosas , Células-Madre Neurales , Nitritos , Elementos de Transición , Ratas , Animales , Fibroínas/metabolismo , Fibroínas/farmacología , Bombyx/metabolismo , Hidrogeles/farmacología , Neuronas/metabolismo , Encéfalo/metabolismo , Lesiones Traumáticas del Encéfalo/metabolismo
14.
J Am Chem Soc ; 146(7): 4351-4356, 2024 02 21.
Artículo en Inglés | MEDLINE | ID: mdl-38334376

RESUMEN

Artificial ion transporters have been explored both as tools for studying fundamental ion transport processes and as potential therapeutics for cancer and channelopathies. Here we demonstrate that synthetic transporters may also be used to regulate the transport of catalytic metal ions across lipid membranes and thus control chemical reactivity inside lipid-bound compartments. We show that acyclic lipophilic pyridyltriazoles enable Pd(II) cations to be transported from the external aqueous phase across the lipid bilayer and into the interior of large unilamellar vesicles. In situ reduction generates Pd(0) species, which catalyze the generation of a fluorescent product. Photocaging the Pd(II) transporter allows for photoactivation of the transport process and hence photocontrol over the internal catalysis process. This work demonstrates that artificial transporters enable control over catalysis inside artificial cell-like systems, which could form the basis of biocompatible nanoreactors for applications such as drug synthesis and delivery or to mediate phototargeted catalyst delivery into cells.


Asunto(s)
Membrana Dobles de Lípidos , Elementos de Transición , Transporte Iónico , Transporte Biológico , Cationes , Catálisis
15.
J Colloid Interface Sci ; 661: 793-801, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38325177

RESUMEN

Novel two-dimensional MXene with unique optical and electrical properties has become a new focus in the field of sensing. In particular, their metallic conductivity, good biocompatibility and high anchoring ability to biomaterials make them attractive candidates. Despite such remarkable properties, there are certain limitations, such as low oxidative stability. MXene-Metal interactions are an effective strategy to maintain the long-term stability of MXene, while also improving the electrochemical activity and optical properties. Herein, a series of MXene/Ag nanocomposites including Ti3C2/Ag, Nb2C/Ag and V2C/Ag were designed based on the surface chemistry characteristics of MXene, where MXene served as the substrate for in-situ growth of silver nanoparticles via self-reduction of Ag(NH3)2+. The results showed that V2C MXene has the strongest self-reducing ability due to its multiple variable valence states, larger interlayer space and more reactive groups. Moreover, V2C/Ag exhibited unexpected oxygen reduction reaction catalytic activity and photothermal performance. In view of which, an electrochemiluminescence-photothermal (ECL-photothermal) immunosensor was developed using V2C/Ag as ECL anchor and photothermal reagent for ultrasensitive detection of Lipolysis stimulated lipoprotein receptor. This work not only provides a simple and effective synthesis method of MXene supported metal nanocomposites, but also provides more inspirations for exploring the efficient biosensing strategies.


Asunto(s)
Técnicas Biosensibles , Nanopartículas del Metal , Nitritos , Neoplasias Ováricas , Elementos de Transición , Femenino , Humanos , Biomarcadores de Tumor , Nanopartículas del Metal/química , Técnicas Biosensibles/métodos , Plata/química , Inmunoensayo
16.
Chemistry ; 30(23): e202400516, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38348814

RESUMEN

The field of bioorthogonal chemistry is rapidly growing, presenting successful applications of organic and transition metal-catalysed reactions in cells and living systems (in vivo). The development of such reactions typically proceeds through many iterative steps focused on biocompatibility and fast reaction kinetics to ensure product formation. However, obtaining kinetic data, even under simulated biological (biomimetic) conditions, remains a challenge due to substantial concentrations of salts and biomolecules hampering the use of typically employed solution-phase analytical techniques. In this study, we explored the suitability of gas evolution as a probe to study kinetics under biomimetic conditions. As proof of concept, we show that the progress of two transition metal-catalysed bioorthogonal chemical reactions can be accurately monitored, regardless of the complexity of the medium. As such, we introduce a protocol to gain more insight into the performance of a catalytic system under biomimetic conditions to further progress iterative catalyst development for in vivo applications.


Asunto(s)
Biomimética , Catálisis , Cinética , Biomimética/métodos , Gases/química , Elementos de Transición/química , Materiales Biomiméticos/química
17.
Int J Biol Macromol ; 263(Pt 2): 130439, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38423420

RESUMEN

Conductive hydrogels become increasing attractive for flexible electronic devices and biosensors. However, challenges still remain in fabrication of flexible hydrogels with high electrical conductivity, self-healing capability and adhesion property. Herein, a conductive hydrogel (PSDM) was prepared by solution-gel method using MXene and dopamine modified polypyrrole as conductive enhanced materials, polyvinyl alcohol and silk fibroin as gel networks, and borax as cross-linking agent. Notably, the PSDM hydrogels not only showed high permeability (13.82 mg∙cm-2∙h-1), excellent stretch ability (1235 %), high electrical conductivity (11.3 S/m) and long-term stability, but also exhibited high adhesion performance and self-healing properties. PSDM hydrogels displayed outstanding sensing performance and durability for monitoring human activities including writing, finger bending and wrist bending. The PSDM hydrogel was made into wearable flexible electrodes and realized accurate, sensitive and reliable detection of human electromyographic and electrocardiographic signals. The sensor was also applied in human-computer interaction by collecting electromyography signals of different gestures for machine learning and gesture recognition. According to 480 groups of data collected, the recognition accuracy of gestures by the electrodes was close to 100 %, indicating that the PSDM hydrogel electrodes possessed excellent sensing performance for high precision data acquisition and human-computer interaction interface.


Asunto(s)
Fibroínas , Nitritos , Prunella , Elementos de Transición , Dispositivos Electrónicos Vestibles , Humanos , Polímeros , Alcohol Polivinílico , Pirroles , Conductividad Eléctrica , Hidrogeles
18.
ACS Sens ; 9(3): 1465-1474, 2024 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-38411899

RESUMEN

In the realm of NH3 gas-sensing applications, the electrically conductive nature of Ti3C2Tx MXene, adorned with surface terminations such as -O and -OH groups, renders it a compelling material. However, the inherent challenges of atmospheric instability and selectivity in the presence of gas mixtures have prompted the exploration of innovative solutions. This work introduces a strategic solution through the deposition of a mixed-matrix membrane (MMM) composed of poly(vinylidene fluoride) (PVDF) as the matrix and zeolitic imidazolate framework-67 (ZIF-67) as the filler. This composite membrane acts as a selective filter, permitting the passage of a specific gas, namely NH3. Leveraging the hydrophobic and chemically inert nature of PVDF, the MMM enhances the atmospheric stability of Ti3C2Tx by impeding water molecules from interacting with the MXene. Furthermore, ZIF-67 is selective to NH3 gas via acid-base interactions within the zeolite group and selective pore size. The Ti3C2Tx sensor embedded in the MMM filter exhibits a modest 1.3% change in the sensing response to 25 ppm of NH3 gas compared to the response without the filter. This result underscores the filter's effectiveness in conferring selectivity and diffusivity, particularly at 35% relative humidity (RH) and 25 °C. Crucially, the hydrophobic attributes of PVDF impart heightened stability to the Ti3C2Tx sensor even amidst varying RH conditions. These results not only demonstrate effective NH3 detection but also highlight the sensor's adaptability to diverse environmental conditions, offering promising prospects for practical applications.


Asunto(s)
Polímeros de Fluorocarbono , Nitritos , Polivinilos , Titanio , Elementos de Transición , Zeolitas , Temperatura
19.
ACS Sens ; 9(3): 1447-1457, 2024 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-38412069

RESUMEN

Developing high-performance chemiresistive gas sensors with mechanical compliance for environmental or health-related biomarker monitoring has recently drawn increasing research attention. Among them, two-dimensional MXene materials hold great potential for room-temperature hazardous gas (e.g., NH3) monitoring regardless of the complicated fabrication process, insufficient 2D/3D flexibilities, and poor environmental sustainability. Herein, a Ti3C2Tx MXene/gelatin ink was developed for patterning electrodes through a facile spray coating. Particularly, the patterned Ti3C2Tx-based coating exhibited good adhesion on the paper substrate against repeated peeling-off and excellent mechanical flexibility against 1000 cyclic stretching. The porous morphology of the coating facilitated the NH3 sensing ability. As a result, the 2D kirigami-shaped NH3 sensor exhibited a good response of 7% to 50 ppm of NH3 with detectable concentrations ranging from 5-500 ppm, decent selectivity over interferences, etc., which could be well-maintained even at 50% stretched state. In addition, with the help of mechanically guided compressive buckling, 3D mesostructured MXene origamis could be obtained, holding promise for detecting the coming direction and height distribution of hazardous gas, e.g., the NH3. More importantly, the as-fabricated MXene/gelatin origami paper could be fully degraded in PBS/H2O2/cellulase solution within 19 days, demonstrating its potential as a high-performance, shape morphable, and environmentally friendly wearable gas sensor.


Asunto(s)
Amoníaco , Celulasa , Nitritos , Elementos de Transición , Gelatina , Peróxido de Hidrógeno
20.
eNeuro ; 11(2)2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38388423

RESUMEN

Electroencephalography (EEG) is an indispensable tool in epilepsy, sleep, and behavioral research. In rodents, EEG recordings are typically performed with metal electrodes that traverse the skull into the epidural space. In addition to requiring major surgery, intracranial EEG is difficult to perform for more than a few electrodes, is time-intensive, and confounds experiments studying traumatic brain injury. Here, we describe an open-source cost-effective refinement of this technique for chronic mouse EEG recording. Our alternative two-channel (EEG2) and sixteen-channel high-density EEG (HdEEG) arrays use electrodes made of the novel, flexible 2D nanomaterial titanium carbide (Ti3C2T x ) MXene. The MXene electrodes are placed on the surface of the intact skull and establish an electrical connection without conductive gel or paste. Fabrication and implantation times of MXene EEG electrodes are significantly shorter than the standard approach, and recorded resting baseline and epileptiform EEG waveforms are similar to those obtained with traditional epidural electrodes. Applying HdEEG to a mild traumatic brain injury (mTBI) model in mice of both sexes revealed that mTBI significantly increased spike-wave discharge (SWD) preictal network connectivity with frequencies of interest in the ß-spectral band (12-30 Hz). These findings indicate that the fabrication of MXene electrode arrays is a cost-effective, efficient technology for multichannel EEG recording in mice that obviates the need for skull-penetrating surgery. Moreover, increased preictal ß-frequency network connectivity may contribute to the development of early post-mTBI SWDs.


Asunto(s)
Conmoción Encefálica , Encéfalo , Nitritos , Elementos de Transición , Masculino , Femenino , Ratones , Animales , Electroencefalografía/métodos , Electrodos , Cráneo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA