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1.
Cell Biol Toxicol ; 39(4): 1627-1639, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36029423

RESUMO

Carbon nanotubes (CNTs) have become promising advanced materials and a new tool to specifically interact with electroresponsive cells. Likewise, conductive polymers (CP) appear promising electroactive biomaterial for proliferation of cells. Herein, we have investigated CNT blends with two different conductive polymers, polypyrrole/CNT (PPy/CNT) and PEDOT/CNT to evaluate the growth, survival, and beating behavior of neonatal rat ventricular myocytes (NRVM). The combination of CP/CNT not only shows excellent biocompatibility on NRVM, after 2 weeks of culture, but also exerts functional effects on networks of cardiomyocytes. NRVMs cultured on CNT-based substrates exhibited improved cellular function, i.e., homogeneous, non-arrhythmogenic, and more frequent spontaneous beating; particularly PEDOT/CNT substrates, which yielded to higher beating amplitudes, thus suggesting a more mature cardiac phenotype. Furthermore, cells presented enhanced structure: aligned sarcomeres, organized and abundant Connexin 43 (Cx43). Finally, no signs of induced hypertrophy were observed. In conclusion, the combination of CNT with CP produces high viability and promotes cardiac functionality, suggesting great potential to generate scaffolding supports for cardiac tissue engineering.


Assuntos
Miócitos Cardíacos , Nanotubos de Carbono , Ratos , Animais , Polímeros , Alicerces Teciduais , Animais Recém-Nascidos , Pirróis
2.
Angew Chem Int Ed Engl ; 62(26): e202301489, 2023 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-37129146

RESUMO

Eutectogels are an emerging family of soft ionic materials alternative to ionic liquid gels and organogels, offering fresh perspectives for designing functional dynamic platforms in water-free environments. Herein, the first example of mixed ionic and electronic conducting supramolecular eutectogel composites is reported. A fluorescent glutamic acid-derived low-molecular-weight gelator (LMWG) was found to self-assemble into nanofibrillar networks in deep eutectic solvents (DES)/poly(3,4-ethylenedioxythiophene) (PEDOT): chondroitin sulfate dispersions. These dynamic materials displayed excellent injectability and self-healing properties, high ionic conductivity (up to 10-2  S cm-1 ), good biocompatibility, and fluorescence imaging ability. This set of features turns the mixed conducting supramolecular eutectogels into promising adaptive materials for bioimaging and electrostimulation applications.


Assuntos
Sulfatos de Condroitina , Corantes , Condutividade Elétrica , Eletrônica , Ácido Glutâmico
3.
Macromol Rapid Commun ; 42(12): e2100100, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33938086

RESUMO

Tailor-made polymers are needed to fully exploit the possibilities of additive manufacturing, constructing complex, and functional devices in areas such as bioelectronics. In this paper, the synthesis of a conducting and biocompatible graft copolymer which can be 3D printed using direct melting extrusion methods is shown. For this purpose, graft copolymers composed by conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT) and a biocompatible polymer polylactide (PLA) are designed. The PEDOT-g-PLA copolymers are synthesized by chemical oxidative polymerization between 3,4-ethylenedioxythiophene and PLA macromonomers. PEDOT-g-PLA copolymers with different compositions are obtained and fully characterized. The rheological characterization indicates that copolymers containing below 20 wt% of PEDOT show the right complex viscosity values suitable for direct ink writing (DIW). The 3D printing tests using the DIW methodology allows printing different parts with different shapes with high resolution (200 µm). The conductive and biocompatible printed patterns of PEDOT-g-PLA show excellent cell growth and maturation of neonatal cardiac myocytes cocultured with fibroblasts.


Assuntos
Tinta , Polímeros , Compostos Bicíclicos Heterocíclicos com Pontes , Humanos , Recém-Nascido , Poliésteres , Redação
4.
Biomacromolecules ; 20(1): 73-89, 2019 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-30543402

RESUMO

3D scaffolds appear to be a cost-effective ultimate answer for biomedical applications, facilitating rapid results while providing an environment similar to in vivo tissue. These biomaterials offer large surface areas for cell or biomaterial attachment, proliferation, biosensing and drug delivery applications. Among 3D scaffolds, the ones based on conjugated polymers (CPs) and natural nonconductive polymers arranged in a 3D architecture provide tridimensionality to cellular culture along with a high surface area for cell adherence and proliferation as well electrical conductivity for stimulation or sensing. However, the scaffolds must also obey other characteristics: homogeneous porosity, with pore sizes large enough to allow cell penetration and nutrient flow; elasticity and wettability similar to the tissue of implantation; and a suitable composition to enhance cell-matrix interactions. In this Review, we summarize the fabrication methods, characterization techniques and main applications of conductive 3D scaffolds based on conductive polymers. The main barrier in the development of these platforms has been the fabrication and subsequent maintenance of the third dimension due to challenges in the manipulation of conductive polymers. In the last decades, different approaches to overcome these barriers have been developed for the production of conductive 3D scaffolds, demonstrating a huge potential for biomedical purposes. Finally, we present an overview of the emerging strategies developed to manufacture 3D conductive scaffolds, the techniques used to fully characterize them, and the biomedical fields where they have been applied.


Assuntos
Condutividade Elétrica , Nanoconjugados/química , Polímeros/química , Engenharia Tecidual/métodos , Alicerces Teciduais/química
5.
Inorg Chem ; 54(15): 7562-70, 2015 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-26176335

RESUMO

C66 is one of the smallest fullerenes that is able to encapsulate more than one metal atom, as in Sc2@C66, as well as to get chlorinated at a low level, C66Cl10 or C66Cl6. We show here, with the help of computations at density functional theory level, that these two means of obtaining derivatives of non-isolated pentagon rule fullerenes are dictated by different factors. Chlorination takes place at temperatures lower than 2000 K, once the neutral fullerenes are formed. Encapsulation is, however, mainly governed by the charge transfer, although the Sc···Sc distance is also playing a role in the stability of Sc2@C66.

6.
ACS Appl Mater Interfaces ; 16(27): 34467-34479, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38936818

RESUMO

Myocardial cardiopathy is one of the highest disease burdens worldwide. The damaged myocardium has little intrinsic repair ability, and as a result, the distorted muscle loses strength for contraction, producing arrhythmias and fainting, and entails a high risk of sudden death. Permanent implantable conductive hydrogels that can restore contraction strength and conductivity appear to be promising candidates for myocardium functional recovery. In this work, we present a printable cardiac hydrogel that can exert functional effects on networks of cardiac myocytes. The hydrogel matrix was designed from poly(vinyl alcohol) (PVA) dynamically cross-linked with gallic acid (GA) and the conductive polymer poly(3,4-ethylenedioxythiophene) (PEDOT). The resulting patches exhibited excellent electrical conductivity, elasticity, and mechanical and contractile strengths, which are critical parameters for reinforcing weakened cardiac contraction and impulse propagation. Furthermore, the PVA-GA/PEDOT blend is suitable for direct ink writing via a melting extrusion. As a proof of concept, we have proven the efficiency of the patches in propagating the electrical signal in adult mouse cardiomyocytes through in vitro recordings of intracellular Ca2+ transients during cell stimulation. Finally, the patches were implanted in healthy mouse hearts to demonstrate their accommodation and biocompatibility. Magnetic resonance imaging revealed that the implants did not affect the essential functional parameters after 2 weeks, thus showing great potential for treating cardiomyopathies.


Assuntos
Compostos Bicíclicos Heterocíclicos com Pontes , Condutividade Elétrica , Hidrogéis , Miócitos Cardíacos , Polímeros , Animais , Camundongos , Compostos Bicíclicos Heterocíclicos com Pontes/química , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Polímeros/química , Polímeros/farmacologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/citologia , Hidrogéis/química , Hidrogéis/farmacologia , Álcool de Polivinil/química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Ácido Gálico/química , Ácido Gálico/farmacologia
7.
Chemistry ; 19(16): 5061-9, 2013 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-23423986

RESUMO

An extensive theoretical study of the Bingel-Hirsch addition of bromomalonate on scandium nitride endohedral fullerenes has been carried out. The prototypical and highly symmetrical Sc3N@I(h)-C80, with a structure that satisfies the isolated pentagon rule (IPR), and the non-IPR Sc3N@D3(6140)-C68 fullerene show analogous reaction paths despite the distinct topology of the carbon networks and different rotation freedom of the internal nitride cluster. For the two metallofullerenes, our results predict that the reaction takes place under kinetic control yielding open-cage fulleroids on [6,6] bonds, which is in good agreement with experimental data. The theoretical studies also show that predicting the reactivity of endohedral metallofullerenes is not straightforward and often an accurate analysis of the potential energy surface is required.

8.
J Org Chem ; 78(19): 9986-90, 2013 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-24004274

RESUMO

Bingel-Hirsch reactions on fullerenes take place under kinetic control. We here predict, by means of DFT methodology, the products of the Bingel-Hirsch addition on non-isolated-pentagon-rule (non-IPR) metallofullerenes Gd3N@C2n (2n = 82, 84), as modeled by closed-shell Y3N@C2n systems. Adducts on [6,6] B-type bonds placed near the pentalene unit are predicted for the two cages, as found for other non-IPR endohedral fullerenes such as Sc3N@C68.


Assuntos
Complexos de Coordenação/química , Fulerenos/química , Gadolínio/química , Isomerismo , Cinética , Estrutura Molecular
9.
Angew Chem Int Ed Engl ; 52(49): 12928-31, 2013 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-24132934

RESUMO

Similar yet different: A one-step regio- and diastereoselective synthesis of three new bis(pyrrolidine)[60]fullerenes, one cis-1 and two unprecedented cis-2 diastereoisomers, is reported. The compounds are easily purified using simple chromatographic techniques, and were fully characterized by spectroscopic techniques and X-ray crystallography. A mechanism for the isomeric conversion observed is proposed.

10.
Macromol Biosci ; 23(11): e2300173, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37392465

RESUMO

Carbon nanotubes (CNT) have proven to be excellent substrates for neuronal cultures, showing high affinity and greatly boosting their synaptic functionality. Therefore, growing cells on CNT offers an opportunity to perform a large variety of neuropathology studies in vitro. To date, the interactions between neurons and chemical functional groups have not been studied extensively. To this end, multiwalled CNT (f-CNT) is functionalized with various functional groups, including sulfonic (-SO3 H), nitro (-NO2 ), amino (-NH2 ), and oxidized moieties. f-CNTs are spray-coated onto untreated glass substrates and are used as substrates for the incubation of neuroblastoma cells (SH-SY5Y). After 7 d, its effect is evaluated in terms of cell attachment, survival, growth, and spontaneous differentiation. Cell viability assays show quite increased proliferation on various f-CNT substrates (CNTs-NO2 > ox-CNTs ≈ CNTs-SO3 H > CNTs ≈ CNTs-NH2 ). Additionally, SH-SY5Y cells show selectively better differentiation and maturation with -SO3 H substrates, where an increased expression of ß-III tubulin is seen. In all cases, intricate cell-CNT networks are observed and the morphology of the cells adopts longer and thinner cellular processes, suggesting that the type of functionalization may have an effect of the length and thickness. Finally, a possible correlation is determined between conductivity of f-CNTs and cell-processes lengths.


Assuntos
Nanotubos de Carbono , Células-Tronco Neurais , Neuroblastoma , Humanos , Dióxido de Nitrogênio , Neurônios
11.
Cir Esp (Engl Ed) ; 101(9): 617-623, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37085134

RESUMO

INTRODUCTION: To describe the design and implementation of a Crisis Resource Management (CRM) training program for the initial assessment of polytrauma patients. METHODS: Prospectively implemented CRM training program in acute-care tertiary hospital by hospital personnel involved in the care of polytraumatisms. The program has a blended format and 23-h duration, including 11 h of online theoretical training followed by 12-h simulation modules and practical cases devoted to the roles of members of the trauma team, functioning of the polytrauma room, and key aspects of teamwork. The Human Factors Attitude Survey (HFAS) was used to assess attitudes related to non-technical skills, and the End-of-Course Critique (ECC) survey to evaluate satisfaction with training. We evaluated changes in the pre- and post-training assessments. RESULTS: Eighty staff personnel (26% specialists, 16% residents, 29% nurses, 14% nursing assistant, 15% stretcher bearer) participated in three editions of the program. Theoretical knowledge improved from a mean (SD) of 5.95 (1.7) to 8.27 (2.1) (P < .0001). In the HFAS, statistically significant differences in 18 of 23 attitudinal markers were observed, with improvements in all items of "leadership" and "roles", in 4 of 5 items of "situational awareness", and in 4 of 8 items of "communication". Mean values obtained in the ECC questionnaire were also very high. CONCLUSIONS: A CRM training model developed for the initial care of polytrauma patients improved theoretical knowledge and participants perceptions and attitudes regarding leadership, communication, roles, and situational awareness of members of the trauma team.


Assuntos
Traumatismo Múltiplo , Humanos , Traumatismo Múltiplo/terapia , Currículo , Conscientização , Liderança , Competência Clínica
12.
J Surg Educ ; 80(5): 706-713, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36882339

RESUMO

OBJECTIVE: To assess acquisition of nontechnical skills (NTS) through clinical simulation cases by healthcare personnel who participated in a Crisis Resource Management (CRM) training program for the initial care of polytraumatisms. DESIGN: Pre-and postintervention study. SETTING: Acute-care teaching hospital in Sabadell, Barcelona (Spain). PARTICIPANTS: Healthcare personnel that composed teamworks providing initial care to polytraumatized patients attended 12-hour simulation training using a SimMan 3G manikin and performed exercises corresponding to 3 clinical scenarios. All simulations lasted 15 to 25 min and were video recorded. The CATS Assessment tool was used for analysis of teamwork NTS, which included 21 behaviors clustered into the categories of coordination, situational awareness, cooperation, communication, and crisis situation. RESULTS: Three editions of the CRM training course were carried out with 12 trauma team groups composed by team leader, anesthesiologist, general surgeon, traumatologist, registered nurses, nursing assistant, and stretcher bearer. There were statistically significant (p <0.001) improvements in the speed of key times of total duration of case resolution, transfusion of hemoderivatives, Focused Assessment Sonography for Trauma, and chest and pelvic X-rays. The percentage of cases correctly resolved improved from 75% to 91.7% but differences were not statistically significant (p = 0.625). Precourse and postcourse results of CATS scores showed a statistically significant increase in the weighted total score as well as in all behavioral categories of coordination, situational awareness, cooperation, communication, and crisis situation. CONCLUSIONS: Simulation-based training of NTS was associated with significant improvements in teamwork behaviors in the setting of the initial care of patients with polytraumatisms.


Assuntos
Traumatismo Múltiplo , Treinamento por Simulação , Cirurgiões , Humanos , Competência Clínica , Treinamento por Simulação/métodos , Traumatismo Múltiplo/terapia , Comunicação , Equipe de Assistência ao Paciente
13.
ACS Macro Lett ; 11(3): 303-309, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35575369

RESUMO

A new photoinitiator system (PIS) based on riboflavin (Rf), triethanolamine, and multiwalled carbon nanobutes (MWCNTs) is presented for visible-light-induced photopolymerization of acrylic monomers. Using this PIS, photopolymerization of acrylamide and other acrylic monomers was quantitative in seconds. The intervention mechanism of CNTs in the PIS was studied deeply, proposing a surface interaction of MWCNTs with Rf which favors the radical generation and the initiation step. As a result, polyacrylamide/MWCNT hydrogel nanocomposites could be obtained with varying amounts of CNTs showing excellent mechanical, thermal, and electrical properties. The presence of the MWCNTs negatively influences the swelling properties of the hydrogel but significantly improves its mechanical properties (Young modulus values) and electric conductivity. The new PIS was tested for 3D printing in a LCD 3D printer. Due to the fast polymerizations, 3D-printed objects based on the conductive polyacrylamide/CNT nanocomposites could be manufactured in minutes.


Assuntos
Nanocompostos , Nanotubos de Carbono , Condutividade Elétrica , Hidrogéis , Impressão Tridimensional
14.
Adv Drug Deliv Rev ; 186: 114315, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35513130

RESUMO

Nano-bionics have the potential of revolutionizing modern medicine. Among nano-bionic devices, body sensors allow to monitor in real-time the health of patients, to achieve personalized medicine, and even to restore or enhance human functions. The advent of two-dimensional (2D) materials is facilitating the manufacturing of miniaturized and ultrathin bioelectronics, that can be easily integrated in the human body. Their unique electronic properties allow to efficiently transduce physical and chemical stimuli into electric current. Their flexibility and nanometric thickness facilitate the adaption and adhesion to human body. The low opacity permits to obtain transparent devices. The good cellular adhesion and reduced cytotoxicity are advantageous for the integration of the devices in vivo. Herein we review the latest and more significant examples of 2D material-based sensors for health monitoring, describing their architectures, sensing mechanisms, advantages and, as well, the challenges and drawbacks that hampers their translation into commercial clinical devices.


Assuntos
Dispositivos Eletrônicos Vestíveis , Humanos , Próteses e Implantes
15.
ACS Appl Polym Mater ; 4(9): 6749-6759, 2022 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-36119408

RESUMO

3D conductive materials such as polymers and hydrogels that interface between biology and electronics are actively being researched for the fabrication of bioelectronic devices. In this work, short-time (5 s) photopolymerizable conductive inks based on poly(3,4-ethylenedioxythiophene) (PEDOT):polystyrene sulfonate (PSS) dispersed in an aqueous matrix formed by a vinyl resin, poly(ethylene glycol) diacrylate (PEGDA) with different molecular weights (M n = 250, 575, and 700 Da), ethylene glycol (EG), and a photoinitiator have been optimized. These inks can be processed by Digital Light 3D Printing (DLP) leading to flexible and shape-defined conductive hydrogels and dry conductive PEDOTs, whose printability resolution increases with PEGDA molecular weight. Besides, the printed conductive PEDOT-based hydrogels are able to swell in water, exhibiting soft mechanical properties (Young's modulus of ∼3 MPa) similar to those of skin tissues and good conductivity values (10-2 S cm-1) for biosensing. Finally, the printed conductive hydrogels were tested as bioelectrodes for human electrocardiography (ECG) and electromyography (EMG) recordings, showing a long-term activity, up to 2 weeks, and enhanced detection signals compared to commercial Ag/AgCl medical electrodes for health monitoring.

16.
Polymers (Basel) ; 13(5)2021 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-33673680

RESUMO

Carbon nanomaterials are at the forefront of the newest technologies of the third millennium, and together with conductive polymers, represent a vast area of indispensable knowledge for developing the devices of tomorrow. This review focusses on the most recent advances in the field of conductive nanotechnology, which combines the properties of carbon nanomaterials with conjugated polymers. Hybrid materials resulting from the embedding of carbon nanotubes, carbon dots and graphene derivatives are taken into consideration and fully explored, with discussion of the most recent literature. An introduction into the three most widely used conductive polymers and a final section about the most recent biological results obtained using carbon nanotube hybrids will complete this overview of these innovative and beyond belief materials.

17.
Polymers (Basel) ; 13(12)2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34208624

RESUMO

Certainly, the success of polythiophenes is due in the first place to their outstanding electronic properties and superior processability. Nevertheless, there are additional reasons that contribute to arouse the scientific interest around these materials. Among these, the large variety of chemical modifications that is possible to perform on the thiophene ring is a precious aspect. In particular, a turning point was marked by the diffusion of synthetic strategies for the preparation of terthiophenes: the vast richness of approaches today available for the easy customization of these structures allows the finetuning of their chemical, physical, and optical properties. Therefore, terthiophene derivatives have become an extremely versatile class of compounds both for direct application or for the preparation of electronic functional polymers. Moreover, their biocompatibility and ease of functionalization make them appealing for biology and medical research, as it testifies to the blossoming of studies in these fields in which they are involved. It is thus with the willingness to guide the reader through all the possibilities offered by these structures that this review elucidates the synthetic methods and describes the full chemical variety of terthiophenes and their derivatives. In the final part, an in-depth presentation of their numerous bioapplications intends to provide a complete picture of the state of the art.

18.
ACS Appl Polym Mater ; 3(6): 2865-2883, 2021 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-35673585

RESUMO

Conducting polymers (CPs) have been attracting great attention in the development of (bio)electronic devices. Most of the current devices are rigid two-dimensional systems and possess uncontrollable geometries and architectures that lead to poor mechanical properties presenting ion/electronic diffusion limitations. The goal of the article is to provide an overview about the additive manufacturing (AM) of conducting polymers, which is of paramount importance for the design of future wearable three-dimensional (3D) (bio)electronic devices. Among different 3D printing AM techniques, inkjet, extrusion, electrohydrodynamic, and light-based printing have been mainly used. This review article collects examples of 3D printing of conducting polymers such as poly(3,4-ethylene-dioxythiophene), polypyrrole, and polyaniline. It also shows examples of AM of these polymers combined with other polymers and/or conducting fillers such as carbon nanotubes, graphene, and silver nanowires. Afterward, the foremost applications of CPs processed by 3D printing techniques in the biomedical and energy fields, that is, wearable electronics, sensors, soft robotics for human motion, or health monitoring devices, among others, will be discussed.

19.
Polymers (Basel) ; 13(3)2021 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-33573011

RESUMO

Carbon nanomaterials (CNMs) and conjugated polymers (CPs) are actively investigated in applications such as optics, catalysis, solar cells, and tissue engineering. Generally, CNMs are implemented in devices where the relationship between the active elements and the micro and nanostructure has a crucial role. However, they present some limitations related to solubility, processibility and release or degradability that affect their manufacturing. CPs, such as poly(3,4-ethylenedioxythiophene) (PEDOT) or derivatives can hide this limitation by electrodeposition onto an electrode. In this work we have explored two different CNMs immobilization methods in 2D and 3D structures. First, CNM/CP hybrid 2D films with enhanced electrochemical properties have been developed using bis-malonyl PEDOT and fullerene C60. The resulting 2D films nanoparticulate present novel electrochromic properties. Secondly, 3D porous self-standing scaffolds were prepared, containing carbon nanotubes and PEDOT by using the same bis-EDOT co-monomer, which show porosity and topography dependence on the composition. This article shows the validity of electropolymerization to obtain 2D and 3D materials including different carbon nanomaterials and conductive polymers.

20.
J Org Chem ; 75(23): 8299-302, 2010 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-21058722

RESUMO

The Bingel-Hirsch reactions on non-isolated pentagon rule (non-IPR) Gd(3)N@C(2n) (2n = 82, 84) are studied. Computational results show that the two metallofullerenes display similar reactivity according to their related topologies. Long C-C bonds with large pyramidalization angles lead to the most stable adducts, the [5,6] bonds in the adjacent pentagon pair being especially favored. The lesser regioselectivity observed for Gd(3)N@C(82) is probably due to the activation of some C-C bonds by means of the metal cluster.

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