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1.
Chin Clin Oncol ; 13(Suppl 1): AB081, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39295399

RESUMO

BACKGROUND: Titanium has been the conventional implant material of choice for fixation in both primary and metastatic spine tumour surgeries (MSTS). However, these implants result in artefact generation during post-operative computed tomography (CT) or magnetic resonance imaging (MRI), resulting in poor planning of radiotherapy (RT) and suboptimal tumour surveillance. Carbon fibre-reinforced polyetheretherketone (CFR-PEEK) implants have gained momentum for instrumentation in MSTS due to their radiolucent properties. This in turn does not sacrifice the biomechanical strength of the implants. In this study, we compared the peri-operative outcomes, post operative imaging artefacts and dosimetricdata of CFR-PEEK implants to titanium implants to asses for potential benefits in post-operative RT planning in patients who underwent MSTS. METHODS: This is a retrospective study involving 42 patients operated for MSTS. Patient-related data including demographics, tumour pathology, intra-operative data, functional outcome, and RT-related data were collected for both groups. All patients were followed-up post-operatively for a minimum of 2 years or until demise, whichever was earlier. RESULTS: In our study, 20 (47.6%) patients had CFR-PEEK implants, while 22 (52.4%) of patients had titanium implants used for MSTS. Both groups of patients had similar clinical outcomes for pain and overall survival predictability pre-operatively (P>0.05). Mean number of levels instrumented by titanium screws were 6.8±2.93, while for the CFR-PEEK screws were 4.07±1.05. Mean volume of artefact generated during post operative CT was 75.1±43.4 mm3 in titanium group and 13.3±14.2 mm3 in CFR-PEEK group (P=0.005). The mean time taken to contour the artefacts was 17.3±5.84 minutes in the titanium group, while the CFR-PEEK group took 9.60±7.17 minutes (P=0.049). CONCLUSIONS: Our study suggests that carbon fibre reinforced PEEK screws significantly reduce artefact generation and the time taken to contour them during post-operative RT planning, while delivering equivalent clinical and functional outcomes as compared to standard titanium implants.


Assuntos
Benzofenonas , Fibra de Carbono , Cetonas , Polietilenoglicóis , Polímeros , Próteses e Implantes , Neoplasias da Coluna Vertebral , Humanos , Estudos Retrospectivos , Masculino , Feminino , Pessoa de Meia-Idade , Polietilenoglicóis/uso terapêutico , Neoplasias da Coluna Vertebral/cirurgia , Neoplasias da Coluna Vertebral/secundário , Adulto , Idoso , Metástase Neoplásica
2.
ACS Appl Mater Interfaces ; 16(39): 52104-52115, 2024 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-39288100

RESUMO

Partial or complete rupture of the tendon can damage the collagen structure, resulting in the disruption of the electrical signal pathway. It is a great challenge to reconstruct the original electrical signal pathway of the tendon and promote the regeneration and functional recovery of defective tendon. In this study, carbon fiber-mediated electrospinning scaffolds were fabricated by wrapping conductive, high-strength, loose single-bundle carbon fibers with nanofiber membranes. Due to the presence of nanofiber membranes, the maximum tensile force of the scaffolds was 2.4 times higher than that of carbon fibers, while providing excellent temporal and spatial prerequisites for tenocytes to adapt to electrical stimulation to accelerate proliferation and expression. The diameter of the carbon fiber monofilaments used in this study was 5.07 ± 1.20 µm, which matched the diameter of tendon collagen, allowing for quickly establishing the connection between the tendon tissue and the scaffold, and better promoting the recovery of the electrical signal pathway. In a rabbit Achilles tendon defect repair model, the carbon fiber-mediated electrospinning scaffold was almost filled with collagen fibers compared to a nonconductive polyethylene glycol terephthalate scaffold. Transcriptome sequencing revealed that fibromodulin and tenomodulin expression were upregulated, and their related proteoglycans and glycosaminoglycan binding proteins pathways were enhanced, which could regulate the TGF-ß signaling pathway and optimize the extracellular matrix assembly, thus promoting tendon repair. Therefore, the scaffold in this study makes up for the shortage of conductive scaffolds for repairing tendon defects, revealing the potential impact of conductivity on the signaling pathway of tendon repair and providing a new approach for future clinical studies.


Assuntos
Fibra de Carbono , Alicerces Teciduais , Animais , Alicerces Teciduais/química , Coelhos , Fibra de Carbono/química , Engenharia Tecidual , Nanofibras/química , Traumatismos dos Tendões/terapia , Traumatismos dos Tendões/patologia , Tendão do Calcâneo/patologia , Tendão do Calcâneo/química , Tendão do Calcâneo/lesões , Tenócitos/metabolismo , Tenócitos/efeitos dos fármacos , Tendões/patologia , Tendões/metabolismo , Colágeno/química , Eletricidade , Resistência à Tração
3.
Int J Biol Macromol ; 279(Pt 4): 135589, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39270909

RESUMO

Good dispersion of carbon fibers is important for the carbon paper production, which is usually achieved using low carbon fiber concentrations and disposable dispersants. In this study, we developed carbomer as a recyclable and high-efficiency dispersant for carbon fibers. When the carbon fiber concentration was 0.1 wt%, carbon fiber suspension showed improved dispersion performance as increasing the carbomer dosage. It exhibited low Turbiscan Stability Index (TSI) of 0.41 and small change of delta backscattering between -0.5 to 0.8 % when using 0.5 wt% carbomer. However, the good dispersibility fade away when increasing the concentration of carbon fibers. Subsequently, the pH of the carbon fiber suspension was adjusted to 7.0 to improve the dispersibility by increasing the viscosity, but causing a worse flowability. Then the pH was further adjusted to 13.0 to ensure good flowability in the wet-forming process and good dispersibility at carbon fiber concentration of 0.5 wt%. More importantly, the dispersant was successfully recycled and still exhibited excellent dispersion effects for carbon fibers after 5 cycles. Notably, the high-efficiency dispersion of carbon fibers and the recyclability of dispersant were achieved simultaneously for the first time, which is suitable for the eco-friendly and sustainable production of carbon paper.


Assuntos
Fibra de Carbono , Fibra de Carbono/química , Viscosidade , Reciclagem , Concentração de Íons de Hidrogênio , Resinas Acrílicas/química , Carbono/química
4.
Jt Dis Relat Surg ; 35(3): 483-490, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-39189556

RESUMO

OBJECTIVES: The aim of the present meta-analysis was to compare the efficacy and safety of the carbon fiber-reinforced polyetheretherketone (CFR-PEEK) and titanium plate for the treatment of proximal humeral fractures (PHFs) from clinical comparative trials. MATERIALS AND METHODS: A comprehensive search of English databases was carried out, such as PubMed, Web of Science, ScienceDirect, Springer and Cochrane Library databases. The RevMan version 5.1 software was applied for statistical analysis, and the mean difference (MD) and risk difference (RD) as the combined variables, and "95%" as the confidence interval (CIs). RESULTS: One randomized-controlled trial and five retrospective controlled studies including 282 PHFs were considered eligible and finally included. Meta-analysis demonstrated that there were significant differences in Constant score (CS) (MD=9.23; 95% CI: 5.02, 13.44; p<0.0001), anterior elevation (MD=18.83; 95% CI: 6.27, 31.38; p=0.003), lateral elevation (MD=18.42; 95% CI: 3.64, 33.19; p=0.01) and adduction (MD=3.53; 95% CI: 0.22, 6.84; p=0.04). No significant differences were observed regarding Constant score compared to the contralateral shoulder, Oxford Shoulder Score, internal rotation, external rotation, screw perforation and cutout, varus/valgus malalignment, humeral head collapse/necrosis, implant removal, and revision surgery between the two groups. CONCLUSION: Compared to titanium plate, CFR-PEEK plate showed better Constant score, anterior elevation, lateral elevation and adduction in treating PHFs. The complications are comparable to those achieved with conventional titanium plates.


Assuntos
Benzofenonas , Placas Ósseas , Fibra de Carbono , Fixação Interna de Fraturas , Polímeros , Fraturas do Ombro , Titânio , Humanos , Fixação Interna de Fraturas/métodos , Fixação Interna de Fraturas/instrumentação , Fraturas do Ombro/cirurgia , Resultado do Tratamento
5.
Analyst ; 149(19): 4915-4921, 2024 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-39143937

RESUMO

Baijiu, a traditional Chinese alcoholic beverage, carries China's rich historical and cultural heritage. Consumers experience varying levels of relaxation and pleasure after consuming different types of Baijiu, with the biological basis of delectation influenced by serotonin and dopamine. In this study, we prepared carbon fiber electrodes modified with surface decorated gold nanoparticles to directly measure the electrochemical response signals in the serum of mice before and after gavage with different types of Baijiu. It was observed that the serum signal change in mice after consuming Baijiu sample 1 (J1) was higher than that of the other two types of Baijiu. Consequently, trace flavor compounds in the Baijiu samples were detected using gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-mass spectrometry (LC-MS), revealing the highest content of L-lactic acid in J1. Mice were intraperitoneally injected with 200 mg kg-1 of L-lactic acid. The changes in dopamine and serotonin in the serum of the injected mice were monitored using a biosensor, and the results were compared with the results of high performance liquid chromatography-triple quadrupole mass spectrometry (HPLC-MS). The findings confirmed that L-lactic acid could indeed stimulate the secretion of both neurotransmitters in mice, suggesting that the trace components in J1 may even exhibit synergistic effects. This study contributes to a deeper understanding of the effects of Baijiu on the body and provides a scientific basis for the production and consumption of Baijiu.


Assuntos
Dopamina , Técnicas Eletroquímicas , Ácido Láctico , Serotonina , Animais , Dopamina/sangue , Dopamina/metabolismo , Serotonina/metabolismo , Serotonina/sangue , Camundongos , Técnicas Eletroquímicas/métodos , Ácido Láctico/sangue , Ácido Láctico/química , Ácido Láctico/análise , Ouro/química , Bebidas Alcoólicas/análise , Nanopartículas Metálicas/química , Masculino , Eletrodos , Técnicas Biossensoriais/métodos , Fibra de Carbono/química
6.
Analyst ; 149(18): 4643-4652, 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39136087

RESUMO

The sensitivity of zinc (Zn(II)) detection using fast-scan cyclic voltammetry (FSCV) with carbon fiber microelectrodes (CFMEs) is low compared to other neurochemicals. We have shown previously that Zn(II) plates to the surface of CFME's and we speculate that it is because of the abundance of oxide functionality on the surface. Plating reduces sensitivity over time and causes significant disruption to detection stability. This limited sensitivity and stability hinders Zn(II) detection, especially in complex matrices like the brain. To address this, we developed plasma-treated gold fiber microelectrodes (AuMEs) which enable sensitive and stable Zn(II) detection with FSCV. Typically, gold fibers are treated using corrosive acids to clean the surface and this step is important for preparing the surface for electrochemistry. Likewise, because FSCV is an adsorption-based technique, it is also important for Zn(II) to adsorb and desorb to prevent irreversible plating. Because of these requirements, careful optimization of the electrode surface was necessary to render the surface for Zn(II) adsorption yet strike a balance between attraction to the surface vs. irreversible interactions. In this study, we employed oxygen plasma treatment to activate the gold fiber surface without inducing significant morphological changes. This treatment effectively removes the organic layer while functionalizing the surface with oxygen, enabling Zn(II) detection that is not possible on untreated gold surfaces. Our results demonstrate significantly improved Zn(II) detection sensitivity and stability on AuME compared to CFME's. Overall, this work provides an advance in our understanding of Zn(II) electrochemistry and a new tool for improved metallotransmitter detection in the brain.


Assuntos
Técnicas Eletroquímicas , Ouro , Microeletrodos , Zinco , Zinco/química , Ouro/química , Técnicas Eletroquímicas/métodos , Técnicas Eletroquímicas/instrumentação , Fibra de Carbono/química , Gases em Plasma/química , Carbono/química , Adsorção , Oxigênio/química
7.
Anal Biochem ; 695: 115640, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39142532

RESUMO

The development of integrated analytical devices is crucial for advancing next-generation point-of-care platforms. Herein, we describe a facile synthesis of a strongly catalytic and durable Nitrogen-doped graphene oxide decorated platinum cobalt (NGO-PtCo) nanocomposite that is conjugated with target-specific DNA aptamer (i-e. MUC1) and grown on carbon fiber. Benefitting from the combined features of the high electrochemical surface area of N-doped GO, high capacitance and stabilization by Co, and high kinetic performance by Pt, a robust, multifunctional, and flexible nanotransducer surface was created. The designed platform was applied for the specific detection of a blood-based oncomarker, CA15-3. The electrochemical characterization proved that nanosurface provides a highly conductive and proficient immobilization support with a strong bio-affinity towards MUC1 aptamer. The specific interaction between CA15-3 and the aptamer alters the surface properties of the aptasensor and the electroactive signal probe generated a remarkable increase in signal intensity. The sensor exhibited a wide dynamic range of 5.0 × 10-2 -200 U mL-1, a low limit of detection (LOD) of 4.1 × 10-2 U mL-1, and good reproducibility. The analysis of spiked serum samples revealed outstanding recoveries of up to 100.03 %, by the proposed aptasensor. The aptasensor design opens new revelations in the reliable detection of tumor biomarkers for timely cancer diagnosis.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Fibra de Carbono , Cobalto , Técnicas Eletroquímicas , Grafite , Mucina-1 , Nanocompostos , Platina , Aptâmeros de Nucleotídeos/química , Técnicas Eletroquímicas/métodos , Grafite/química , Humanos , Mucina-1/sangue , Mucina-1/análise , Cobalto/química , Nanocompostos/química , Platina/química , Técnicas Biossensoriais/métodos , Fibra de Carbono/química , Limite de Detecção
8.
Chemosphere ; 364: 143051, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39127191

RESUMO

In this study, acid-modified activated carbon fibers (ACF-Ps) were synthesized by phosphorylation. Three different types of ACF-based adsorbents functionalized with PO43-, P2O74-, or P3O105- ions, namely, ACF-P1, ACF-P2, and ACF-P3, were prepared by phosphorylating ACF with trisodium phosphate (Na3PO4), sodium dihydrogen pyrophosphate (Na2H2P2O5), and sodium tripolyphosphate (Na5P3O10), respectively, and utilized as adsorbents to remove cesium ions (Cs+) from aqueous solutions. Among the tested adsorbents, ACF-P3 exhibited the highest Cs+ adsorption capacity of 37.59 mg g-1 at 25 °C and pH 7 which is higher than that of ACF (5.634 mg g-1), ACF-P1 (19.38 mg g-1), and ACF-P2 (30.12 mg g-1) under the same experimental conditions. More importantly, the Cs+ removal efficiencies of ACF-P3 (82.90%), ACF-P2 (66.2%), ACF-P1 (34.2%) were 29.3-, 23.4-, and 12.11-fold higher than that of un-treated ACF (2.83%). The results suggested that the phosphorylation with Na5P3O10 is highly suitable for Cs+ adsorption which effectively functionalizes ACF with a greater number of phosphate functional groups. Adsorption and kinetic data well-fitted the Langmuir isotherm and pseudo-second-order model, respectively, which indicated the monolayer adsorption of Cs+ onto ACF-P1, ACF-P2, and ACF-P3 which were largely controlled by chemisorption. Overall, phosphoric acids containing different phosphate-based polyanions (PO43-, P2O74-, or P3O105-) enriched -OH and/or -COOH surface functional groups of ACF in addition to P-containing surface groups (PO, C-P-O, C-O-P, and P-O) and facilitated the Cs+ adsorption through surface complexation and electrostatic interactions.


Assuntos
Césio , Ácidos Fosfóricos , Poluentes Químicos da Água , Ácidos Fosfóricos/química , Adsorção , Césio/química , Poluentes Químicos da Água/química , Fibra de Carbono/química , Carvão Vegetal/química , Cinética , Íons/química , Purificação da Água/métodos , Concentração de Íons de Hidrogênio
9.
Int J Biol Macromol ; 277(Pt 4): 134529, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39111485

RESUMO

Living organisms have developed a miraculous biomineralization strategy to form multistage organic-inorganic composites through the orderly assembly of hard/soft substances, achieving mechanical enhancement of materials from the nanoscale to the macroscale. Inspired by biominerals, this study used polydopamine (PDA) coating as a template to induce the growth of hydroxyapatite (HAP) on the surface of carbon fibers (CFs) for enhancing the interfacial properties of the CF/epoxy resin composites. This polydopamine-assisted hydroxyapatite formation (pHAF) biomimetic mineralization strategy constructs soft/hard ordered structure on the CF surface, which not only improves the chemical reaction activity of the CFs but also increases the fiber surface roughness. This, in turn, enhances the interaction and loading delivery among the fibers and the matrix. Compared to the untreated carbon fiber/epoxy resin (CF/EP) composites, the prepared composites showed a substantial enhancement in interlaminar shear strength (ILSS), flexural strength, and interfacial shear strength (IFSS), with improvements of 45.2 %, 46.9 %, and 60.5 %, respectively. This can be attributed to the HAP nanolayers increasing the adhesion and mechanical interlocking with the CFs to the matrix. This study provides an interface modification method of biomimetic mineralization for the preparation of high strength CF composites.


Assuntos
Fibra de Carbono , Durapatita , Indóis , Polímeros , Indóis/química , Durapatita/química , Polímeros/química , Fibra de Carbono/química , Materiais Biomiméticos/química , Biomimética/métodos , Fenômenos Mecânicos , Resistência ao Cisalhamento , Propriedades de Superfície , Resinas Epóxi/química
10.
Int J Mol Sci ; 25(15)2024 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-39126084

RESUMO

Nowadays, owing to the new technological and industrial requirements for equipment, such as flexibility or multifunctionally, the development of all-solid-state supercapacitors and Li-ion batteries has become a goal for researchers. For these purposes, the composite material approach has been widely proposed due to the promising features of woven carbon fiber as a substrate material for this type of material. Carbon fiber displays excellent mechanical properties, flexibility, and high electrical conductivity, allowing it to act as a substrate and a collector at the same time. However, carbon fiber's energy-storage capability is limited. Several coatings have been proposed for this, with nanostructured transition metal oxides being one of the most popular due to their high theoretical capacity and surface area. In this overview, the main techniques used to achieve these coatings-such as solvothermal synthesis, MOF-derived obtention, and electrochemical deposition-are summarized, as well as the main strategies for alleviating the low electrical conductivity of transition metal oxides, which is the main drawback of these materials.


Assuntos
Fibra de Carbono , Capacitância Elétrica , Fontes de Energia Elétrica , Eletrodos , Lítio , Nanoestruturas , Óxidos , Lítio/química , Fibra de Carbono/química , Óxidos/química , Nanoestruturas/química , Elementos de Transição/química , Condutividade Elétrica , Metais/química
11.
J Biomed Mater Res B Appl Biomater ; 112(8): e35463, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39115314

RESUMO

Secondary healing of fractured bones requires an application of an appropriate fixator. In general, steel or titanium devices are used mostly. However, in recent years, composite structures arise as an attractive alternative due to high strength to weight ratio and other advantages like, for example, radiolucency. According to Food and Drug Administration (FDA), the only unidirectionally reinforced composite allowed to be implanted in human bodies is carbon fiber (CF)-reinforced poly-ether-ether-ketone (PEEK). In this work, the healing process of long bone assembled with CF/PEEK plates with cross- and angle-ply lay-up configurations is studied in the framework of finite element method. The healing is simulated by making use of the mechanoregulation model basing on the Prendergast theory. Cells transformation is determined by the octahedral shear strain and interstitial fluid velocity. The process runs iteratively assuming single load cycle each day. The fracture is subjected to axial and transverse forces. In the computations, the Abaqus program is used. It is shown that the angle-ply lamination scheme of CF/PEEK composite seems to provide better conditions for the transformation of the soft callus into the bone tissue.


Assuntos
Benzofenonas , Placas Ósseas , Fibra de Carbono , Consolidação da Fratura , Cetonas , Polietilenoglicóis , Polímeros , Cetonas/química , Fibra de Carbono/química , Polietilenoglicóis/química , Polímeros/química , Humanos , Carbono/química , Fraturas Ósseas , Análise de Elementos Finitos
12.
J Biomed Mater Res B Appl Biomater ; 112(9): e35467, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39180195

RESUMO

The objective of the present study was to evaluate the carbon fiber obtained from textile PAN fiber, in its different forms, as a potential scaffolds synthetic bone. Thirty-four adult rats were used (Rattus norvegicus, albinus variation), two critical sized bone defects were made that were 5 mm in diameter. Twenty-four animals were randomly divided into four groups: control (C)-bone defect + blood clot, non-activated carbon fiber felt (NACFF)-bone defect + NACFF, activated carbon fiber felt (ACFF)-bone defect + ACFF, and silver activated carbon fiber felt (Ag-ACFF)-bone defect + Ag-ACFF, and was observed by 15 and 60 days for histomorphometric, three-dimensional computerized microtomography (microCT) and mineral apposition analysis. On histomorphometric and microCT analyses, NACFF were associated with higher proportion of neoformed bone and maintenance of bone structure. On fluorochrome bone label, there was no differences between the groups. NACFF has shown to be a promising synthetic material as a scaffold for bone regeneration.


Assuntos
Regeneração Óssea , Fibra de Carbono , Carbono , Alicerces Teciduais , Microtomografia por Raio-X , Animais , Ratos , Regeneração Óssea/efeitos dos fármacos , Alicerces Teciduais/química , Carbono/química , Fibra de Carbono/química , Masculino , Têxteis , Brasil , Teste de Materiais , Ratos Wistar
13.
Methods Mol Biol ; 2835: 307-315, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39105926

RESUMO

Cell therapy and engineered tissue creation based on the use of human stem cells involves cell isolation, expansion, and cell growth and differentiation on the scaffolds. Microbial infections dramatically can affect stem cell survival and increase the risk of implant failure. To prevent these events, it is necessary to develop new materials with antibacterial properties for coating scaffold surfaces as well as medical devices, and all other surfaces at high risk of contamination. This chapter describes strategies for obtaining antibacterial blends for coating inert surfaces (polymethylmethacrylate, polycarbonate, Carbon Fiber Reinforced Polymer (CFRP)). In particular, the procedures for preparing antibacterial blends by mixing polymer resins with two types of antibacterial additives and depositing these blends on inert surfaces are described.


Assuntos
Células-Tronco , Engenharia Tecidual , Humanos , Engenharia Tecidual/métodos , Células-Tronco/citologia , Propriedades de Superfície , Alicerces Teciduais/química , Antibacterianos/farmacologia , Cimento de Policarboxilato/química , Técnicas de Cultura de Células/métodos , Polimetil Metacrilato/química , Fibra de Carbono/química , Carbono/química , Anti-Infecciosos/farmacologia
14.
J Colloid Interface Sci ; 676: 217-226, 2024 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-39024822

RESUMO

Developing multifunctional materials which could simultaneously possess anti-bacterial ability and electromagnetic (EM) absorption ability during medical care is quite essential since the EM waves radiation and antibiotic-resistant bacteria are threatening people's health. In this work, the multifunctional carbon fiber/Ti3C2Tx MXene (CM) were synthesized through repeated dip-coating and following in-situ growth method. The as-fabricated CF/MXene displayed outstanding EM wave absorption and highly efficient photothermal converting ability. The minimum reflection loss (RL) of -57.07 dB and ultra-broad absorption of 7.74 GHz could be achieved for CM composites. By growth of CoNi-layered double hydroxides (LDHs) sheets onto MXene, the absorption bandwidth for carbon fiber/Ti3C2Tx MXene layered double hydroxides (CML) could be reach 5.44 GHz, which could cover the whole Ku band. The excellent photothermal effect endow the CM composites with excellent antibacterial performance. The antibacterials tests indicated that nearly 100 % bactericidal efficiency against E. acoil and S. aureus was obtained for the CM composite after exposure to near-infrared region (NIR) irradiation. This work provides a promising candidate to combat medical device-related infections and EM pollution.


Assuntos
Antibacterianos , Fibra de Carbono , Escherichia coli , Raios Infravermelhos , Staphylococcus aureus , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Staphylococcus aureus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Fibra de Carbono/química , Radiação Eletromagnética , Testes de Sensibilidade Microbiana , Titânio/química , Titânio/farmacologia , Lasers , Tamanho da Partícula , Propriedades de Superfície
15.
Biomed Mater Eng ; 35(4): 401-414, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38995767

RESUMO

BACKGROUND: The prosthetic foot is an essential component of the prosthetic limb used by people who suffer from amputation. The prosthetic foot or limb is expensive in developing countries and cannot be used by most people with special needs. OBJECTIVE: In this study, an uncomplicated prosthetic foot is designed that can be manufactured at low costs using 3D printer technology and can be provided to a wide range of amputees. The foot was designed using CAD software and analyzed using ANSES. METHODS: Carbon fiber material was chosen to be suitable for the manufacturing process using 3D printer technology. The selected material was tested in tensile and fatigue tests to determine its mechanical properties. The numerical analysis was carried out assuming the use of an artificial foot by a patient weighing 85 kg. RESULTS: The results showed that the material proposed for manufacturing has good mechanical properties for this application. The results of the engineering analysis also showed that the model has successfully passed the design process and is reliable for use by amputees. CONCLUSION: The success model designed in this study in the numerical analysis process gives reliability to the use of this design to manufacture the prosthetic foot.


Assuntos
Membros Artificiais , Simulação por Computador , , Impressão Tridimensional , Desenho de Prótese , Humanos , Resistência à Tração , Desenho Assistido por Computador , Amputados/reabilitação , Fibra de Carbono/química , Teste de Materiais , Análise de Elementos Finitos , Estresse Mecânico
16.
Int J Biol Macromol ; 275(Pt 1): 133568, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38969033

RESUMO

This paper initially examines the feasibility and effectiveness on interfacial adhesion of composites when grafting nanoparticle-structured polydopamine (PDA) and chitosan around carbon fiber periphery. The resulting interfacial shear strength was maximized as 92.3 MPa, delivering 50.1 % and 15.7-16.2 % gains over those of control fiber and only polydopamine nanospheres (PDANPs) or only chitosan modified fiber composites. Measuring surface morphology and thermal stability of fibers found that abundant PDANPs well adhered with the help of chitosan, highlighting nanoscale size effects and intrinsic adhesiveness of PDA. Under good wettability, rich and dense interfacial interactions (covalent and hydrogen bond, electrostatic interaction, and π conjugation) caused by PDANPs/chitosan coating provides impetus for effective stress transfer. Additionally, the stable "soft-rigid" combination of chitosan and PDANPs adds the efficiency of crack passivation. As such, it is hoped that this work could fully explore the possibility of PDA geometry in interphase engineering of fiber composites.


Assuntos
Fibra de Carbono , Quitosana , Indóis , Nanosferas , Polímeros , Quitosana/química , Indóis/química , Nanosferas/química , Polímeros/química , Fibra de Carbono/química , Molhabilidade
17.
Int J Biol Macromol ; 276(Pt 1): 133877, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39009255

RESUMO

The adhesive strength between the sizing agent and carbon fiber (CF) plays a crucial role in improving the interfacial properties of composites, while such a vital aspect has been consistently disregarded. In this study, a hyperbranched waterborne polyurethane (HWPU) sizing agent was synthesized from biogenetically raw materials including gallic acid, l-Lysine diisocyanate and amylopectin. Concurrently, hydrogen-bonded cross-linked network structures were established utilizing a botanical polyphenol tannin as coupling agent to effectively connect CF with HWPU. This meticulous process yielded CF/nylon 6 composites with improved properties and their mechanical characteristics were systematically investigated. The findings showcased a noteworthy boost in flexural strength and interlaminar shear strength (ILSS), showing enhancements of 54.6 % and 61.4 %, respectively, surpassing those of untreated CF. Furthermore, the interfacial shear strength (IFSS) test indicated a remarkable 70.3 % improvement. This approach presents a highly promising concept aimed at developing sustainable green waterborne polyurethane sizing agent and improving the interfacial performance of CF composite materials.


Assuntos
Amilopectina , Fibra de Carbono , Ligação de Hidrogênio , Polifenóis , Poliuretanos , Poliuretanos/química , Polifenóis/química , Fibra de Carbono/química , Amilopectina/química , Água/química , Resistência ao Cisalhamento
18.
Food Chem ; 459: 140378, 2024 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38991446

RESUMO

In this study, a hydrothermal process was utilized to grow mixed-valence CuFe2O4/Cu0 nanosheets on carbon fiber paper, forming a three-dimensional hierarchical electrode (CuFe2O4/Cu0@CFP). The ordered array structure, coupled with the porous bowl-like structure, enhances the exposure of more electrode active sites and facilitates analyte penetration, thus enhancing the electrode sensing performance. As a binder-free sensor, the CuFe2O4/Cu0@CFP sensor exhibited remarkable sensitivity in detecting Malachite Green (MG), Sunset Yellow (SY) and Tartrazine (TA) over wide concentration ranges: 0.1-300 µM for MG (R2 = 0.994), 0.005-200 µM for SY (R2 = 0.996), and 0.005-300 µM for TA (R2 = 0.995) with low detection limits of 0.033 µM for MG, 0.0016 µM for SY, and 0.0016 µM for TA (S/N = 3), respectively. Additionally, the 3D CuFe2O4/Cu0@CFP sensor detected MG, SY, and TA in a mixed solution with satisfactory results. It also performs well in beverage, fruit juice powder, and jelly samples, with results matching those from HPLC.


Assuntos
Compostos Azo , Cobre , Nanoestruturas , Corantes de Rosanilina , Tartrazina , Cobre/química , Cobre/análise , Tartrazina/análise , Tartrazina/química , Nanoestruturas/química , Corantes de Rosanilina/química , Corantes de Rosanilina/análise , Compostos Azo/química , Compostos Azo/análise , Fibra de Carbono/química , Contaminação de Alimentos/análise , Técnicas Eletroquímicas/instrumentação , Limite de Detecção , Corantes de Alimentos/análise , Corantes de Alimentos/química , Papel
19.
ACS Appl Bio Mater ; 7(8): 5397-5410, 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-39051842

RESUMO

Photocatalytic antimicrobials, as emerging advanced oxidative antimicrobial materials, have the advantages of low price and long-lasting antimicrobial properties. Nevertheless, with catalysts increasingly trending toward nanoscale dimensions, the environmental challenge of catalyst recycling becomes more pronounced. In this paper, we propose utilizing one-dimensional carbon fiber as a substrate, employing the nucleating agent method to induce Titanium dioxide (TiO2) growth on the fiber surface. Furthermore, the material's band gap underwent modification through hydrogen calcination, thus resulting in the attainment of hierarchical black TiO2/carbon fiber composites with visible light-driven capabilities. The characterization of the materials was conducted via scanning electron microscope (SEM), X-ray diffraction (XRD), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). The results revealed that when the black hydrogenated TiO2 was composited with carbon fiber, the Schottky heterojunction was formed, and thus effectively improved the photocatalytic effect of the composites. Notably, the degradation rate of methylene blue achieved 96.25% within 150 min when utilizing black TiO2/carbon fiber composites, while the inactivation rate of Escherichia coli (E. coli) reached 97.58% within 0.5 h and attained complete inactivation within 60 min.


Assuntos
Fibra de Carbono , Escherichia coli , Teste de Materiais , Tamanho da Partícula , Titânio , Titânio/química , Escherichia coli/efeitos dos fármacos , Catálise , Fibra de Carbono/química , Processos Fotoquímicos , Luz , Propriedades de Superfície , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Antibacterianos/síntese química , Carbono/química , Azul de Metileno/química
20.
Waste Manag ; 187: 134-144, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39032436

RESUMO

Here we report a novel chemical recycling of carbon fiber-reinforced plastic (CFRP) using meta-chloroperoxybenzoic acid (mCPBA) as the representative oxidizing agent. The optimal decomposition conditions for the epoxy (EP) resin in CFRP were investigated by varying mCPBA concentration and reaction time. The CFRP decomposed completely within 6 h using a 1.5 M mCPBA solution at 40 °C. Tensile strength of recovered CF (r-CF) measured 4.4 GPa, 93.6% of virgin CF (v-CF), and electrical conductivity reached 590 S/cm, 95% of v-CF. Furthermore, the interfacial shear strength (IFSS) of the recovered carbon fibers (r-CF) using EP resin and polyamide 6 (PA6) was analyzed. For EP resin, the IFSS of r-CF was 88 MPa, a 26 % increase compared to v-CF. In the case of PA6 resin, IFSS values were 80 MPa for r-CF, a 17% improvement over v-CF. The study highlights superior mechanical properties and favorable IFSS of r-CF, positioning them as promising for composite regeneration. Remarkably, this method operated at relatively low temperatures compared to existing technologies, with energy consumption recorded at 35 MJ/kg, establishing it as the most energy-efficient recycling method available.


Assuntos
Fibra de Carbono , Reciclagem , Resistência ao Cisalhamento , Fibra de Carbono/química , Reciclagem/métodos , Plásticos/química , Resinas Epóxi/química , Resistência à Tração , Carbono/química , Caprolactama/análogos & derivados , Polímeros
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