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1.
J Environ Sci (China) ; 149: 99-112, 2025 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-39181682

RESUMO

With the increasing demand for water in hydroponic systems and agricultural irrigation, viral diseases have seriously affected the yield and quality of crops. By removing plant viruses in water environments, virus transmission can be prevented and agricultural production and ecosystems can be protected. But so far, there have been few reports on the removal of plant viruses in water environments. Herein, in this study, easily recyclable biomass-based carbon nanotubes catalysts were synthesized with varying metal activities to activate peroxymonosulfate (PMS). Among them, the magnetic 0.125Fe@NCNTs-1/PMS system showed the best overall removal performance against pepper mild mottle virus, with a 5.9 log10 removal within 1 min. Notably, the key reactive species in the 0.125Fe@NCNTs-1/PMS system is 1O2, which can maintain good removal effect in real water matrices (river water and tap water). Through RNA fragment analyses and label free analysis, it was found that this system could effectively cleave virus particles, destroy viral proteins and expose their genome. The capsid protein of pepper mild mottle virus was effectively decomposed where serine may be the main attacking sites by 1O2. Long viral RNA fragments (3349 and 1642 nt) were cut into smaller fragments (∼160 nt) and caused their degradation. In summary, this study contributes to controlling the spread of plant viruses in real water environment, which will potentially help protect agricultural production and food safety, and improve the health and sustainability of ecosystems.


Assuntos
Biomassa , Nanotubos de Carbono , Nanotubos de Carbono/química , Vírus de Plantas/fisiologia , Purificação da Água/métodos , Tobamovirus , Peróxidos
2.
Carbohydr Polym ; 344: 122541, 2024 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-39218558

RESUMO

The burgeoning requirement for purified biomacromolecules in biopharmaceutical industry has amplified the exigency for advanced chromatographic separation techniques. Herein, macroporous cellulose microspheres (CCMs) with micron-sized pores are produced by a facile regulation via carbon nanotubes (CNTs). In this strategy, the incorporation of CNTs breaks the homogeneous regeneration of the cellulose, thus providing anisotropic phase force to produce macropores. The CCMs have manifested a faster mass transfer rate and more available adsorption sites owing to well-defined macropores (2.69 ± 0.57 µm) and high specific surface area (147.47 m2 g-1). Further, CCMs are functionalized by quaternary ammonium salts (GTAc-CCMs) and utilized as anion adsorbents to adsorb pancreatic kininogenase (PK). The prepared GTAc-CCMs show rapid adsorption kinetics for PK at pH 6.0, reaching 90 % equilibrium within 60 min. Also, GTAc-CCMs for PK exhibit high adsorptive capacity (632.50 mg g-1), excellent recyclability (> 80 % removal amount after 10 cycles) and selectivity especially at pH 6.0. Notably, the GTAc-CCMs have been successfully applied in a fixed-bed chromatography process, indicating their potential as an effective chromatographic medium for rapid separation of biomacromolecules.


Assuntos
Celulose , Microesferas , Nanotubos de Carbono , Nanotubos de Carbono/química , Adsorção , Celulose/química , Porosidade , Cinética , Compostos de Amônio Quaternário/química , Concentração de Íons de Hidrogênio , Separação de Fases
3.
Nanotechnology ; 35(46)2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39221963

RESUMO

The study utilized transition metal chalcogenide, molybdenum diselenide (MoSe2), for application in the field of bioelectrochemical sensing. The MoSe2was combined with carbon nanotubes (CNTs) by chemical vapor deposition to enhance the specific surface area and improve the detection sensitivity. To further increase the contact area between the electrolyte and the electrode, photolithography techniques were employed to fabricate hive-shaped CNTs, thereby enhancing the specific surface area. Next, cholesterol oxidase (ChOx) was coated onto the electrode material, creating a cholesterol biosensor. Cyclic voltammetry was utilized to detect the concentration of cholesterol. The experiment involved segmented testing for cholesterol concentrations ranging from 0µM to 10 mM. Excellent sensitivity, low detection limits, and high accuracy were achieved. In the cholesterol concentration range of 0µM-100µM, the experiment achieved the highest sensitivity of 4.44µAµM⋅cm-2. Consequently, all data indicated that ChOx/MoSe2/CNTs functioned as an excellent cholesterol sensor in the study.


Assuntos
Técnicas Biossensoriais , Colesterol Oxidase , Colesterol , Técnicas Eletroquímicas , Molibdênio , Nanotubos de Carbono , Nanotubos de Carbono/química , Colesterol/análise , Colesterol/química , Técnicas Biossensoriais/métodos , Molibdênio/química , Técnicas Eletroquímicas/métodos , Colesterol Oxidase/química , Colesterol Oxidase/metabolismo , Limite de Detecção , Eletrodos , Enzimas Imobilizadas/química
4.
PLoS One ; 19(8): e0305555, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39121165

RESUMO

Two-dimensional material hexagonal boron nitride (h-BN), and its one-dimensional thin strips, boron nitride nanoribbons (BNNRs) are electrically insulating with high thermal stability, making them excellent thermal conductors suitable for high-temperature application. BNNRs are wide bandgap semiconductors with bandgaps ranging from 4 to 6 eV. This study investigates the electronic properties of BNNRs with single vacancy defects in armchair and zigzag configurations. The nearest-neighbour tight-binding model and numerical method were used to simulate the electronic properties of BNNRs with a single vacancy, including band structure and local density of states. The alpha and beta matrices were adjusted to account for missing boron or nitrogen atoms. Furthermore, a small perturbations were introduced to model the effects of impurities and edge imperfections. The simulation result from this work was compared with pristine BNNRs to examine the impact of a single vacancy on their electronic properties. The findings reveal that both armchair and zigzag BNNRs with single vacancy defects exhibit distorted band structures and local density of states due to the delocalization of pz orbitals. The valence bands show a higher concentration of nitrogen, while the conduction bands are richer in boron. These findings provide insights into how vacancy defects and edge perturbations can influence the electronic properties of BNNRs, which can guide the design and optimization of BNNR-based electronic devices in future research.


Assuntos
Compostos de Boro , Nanotubos de Carbono , Compostos de Boro/química , Nanotubos de Carbono/química , Elétrons , Semicondutores
5.
Sci Rep ; 14(1): 19055, 2024 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-39154029

RESUMO

Beta-tricalcium phosphate (ß-TCP) scaffolds manufactured through the foam replication method are widely employed in bone tissue regeneration. The mechanical strength of these scaffolds is a significant challenge, partly due to the rheological properties of the original suspension. Various strategies have been explored to enhance the mechanical properties. In this research, ß-TCP scaffolds containing varying concentrations (0.25-1.00 wt%) of multi-walled carbon nanotubes (MWCNT) were developed. The findings indicate that the addition of MWCNTs led to a concentration-dependent improvement in the viscosity of ß-TCP suspensions. All the prepared slurries exhibited viscoelastic behavior, with the storage modulus surpassing the loss modulus. The three time interval tests revealed that MWCNT-incorporated ß-TCP suspensions exhibited faster structural recovery compared to pure ß-TCP slurries. Introducing MWCNT modified compressive strength, and the optimal improvement was obtained using 0.75 wt% MWCNT. The in vitro degradation of ß-TCP was also reduced by incorporating MWCNT. While the inclusion of carbon nanotubes had a marginal negative impact on the viability and attachment of MC3T3-E1 cells, the number of viable cells remained above 70% of the control group. Additionally, the results demonstrated that the scaffold increased the expression level of osteocalcin, osteoponthin, and alkaline phosphatase genes of adiposed-derived stem cells; however, higher levels of gene expersion were obtained by using MWCNT. The suitability of MWCNT-modified ß-TCP suspensions for the foam replication method can be assessed by evaluating their rheological behavior, aiding in determining the critical additive concentration necessary for a successful coating process.


Assuntos
Fosfatos de Cálcio , Nanotubos de Carbono , Engenharia Tecidual , Alicerces Teciduais , Fosfatos de Cálcio/química , Nanotubos de Carbono/química , Alicerces Teciduais/química , Engenharia Tecidual/métodos , Animais , Camundongos , Linhagem Celular , Osso e Ossos/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Teste de Materiais , Regeneração Óssea/efeitos dos fármacos , Osteoblastos/metabolismo , Osteoblastos/efeitos dos fármacos , Osteoblastos/citologia , Viscosidade
6.
Environ Sci Technol ; 58(33): 14675-14686, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39102504

RESUMO

The escalating levels of plastic waste and energy crises underscore the urgent need for effective waste-to-energy strategies. This study focused on converting polypropylene wastes into high-value products employing various iron-based catalysts and microwave radiative thermal processing. The Al-Fe catalysts exhibited exceptional performance, achieving a hydrogen utilization efficiency of 97.65% and a yield of 44.07 mmol/g PP. The gas yields increased from 19.99 to 94.21 wt % compared to noncatalytic experiments. Furthermore, this catalytic system produced high-value bamboo-shaped carbon nanotubes that were absent in other catalysts. The mechanism analysis on catalytic properties and product yields highlighted the significance of oxygen vacancies in selecting high-value products through two adsorption pathways. Moreover, the investigation examined the variations in product distribution mechanisms between conventional and microwave pyrolysis, in which microwave conditions resulted in 4 times higher hydrogen yields. The technoeconomic assessment and Monte Carlo risk analysis further compared the disparity. The microwave technique had a remarkable internal rate of return (IRR) of 39%, leading to an income of $577/t of plastic with a short payback period of 2.5 years. This research offered sustainable solutions for the plastic crisis, validating the potential applicability of commercializing the research outcomes in real-world scenarios.


Assuntos
Hidrogênio , Micro-Ondas , Nanotubos de Carbono , Plásticos , Nanotubos de Carbono/química , Hidrogênio/química , Catálise
7.
Mikrochim Acta ; 191(9): 540, 2024 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-39150580

RESUMO

For the first time the sensitive determination of carbendatim (CRB) is reported utilizing a well-designed sensing architecture based on vanadium diselenide-multiwalled carbon nanotube (VSMC). FTIR, XRD, FESEM, EDS, and EIS were employed to evaluate the sensor's structural integrity, and the results demonstrated the successful integration of nanomaterials, resulting in a robust and sensitive electrochemical sensor. Cyclic voltammetry (CV) and chronoamperometric (CA) investigations showed that the sensor best performed at pH 8.0 (BRB) with an excellent detection limit of 9.80 nM with a wide linear range of 0.1 to 10.0 µM. A more thermodynamically viable oxidation of CRB was observed at the VSMC/GCE, with a shift of 200 mV in peak potential towards the less positive side compared with the unmodified GCE. In addition, the sensor demonstrated facile heterogeneous electron transfer, favorable anti-fouling traits in the presence of a wide range of interferents, good stability, and reproducible analytical performance. Finally, the developed sensor was validated for real-time quantification of CRB from spiked water, food, and bio-samples, which depicted acceptable recoveries (98.6 to 101.5%) with RSD values between 0.35 and 2.23%. Further, to derive the possible sensing mechanism, the valence orbitals projected density of states (PDOS) for C, H, and N atoms of an isolated CRB molecule, VSe2 + CNT and VSe2 + CNT + CRB were calculated using density functional theory (DFT) calculations. The dominant charge transfer from the valence 2p-orbitals of the C and N atoms of CRB to CNT is responsible for the electrochemical sensing of CRB molecules.


Assuntos
Benzimidazóis , Carbamatos , Técnicas Eletroquímicas , Limite de Detecção , Nanotubos de Carbono , Nanotubos de Carbono/química , Técnicas Eletroquímicas/métodos , Técnicas Eletroquímicas/instrumentação , Carbamatos/análise , Carbamatos/química , Benzimidazóis/química , Benzimidazóis/análise , Contaminação de Alimentos/análise , Eletrodos , Poluentes Químicos da Água/análise , Animais
8.
Biosens Bioelectron ; 264: 116686, 2024 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-39173339

RESUMO

Cannabinoids are involved in physiological and neuromodulatory processes through their interactions with the human cannabinoid receptor-based endocannabinoid system. Their association with neurodegenerative diseases and brain reward pathways underscores the importance of evaluating and modulating cannabinoid activity for both understanding physiological mechanisms and developing therapeutic drugs. The use of agonists and antagonists could be strategic approaches for modulation. In this study, we introduce a bioelectronic sensor designed to monitor cannabinoid binding to receptors and assess their agonistic and antagonistic properties. We produced human cannabinoid receptor 1 (hCB1R) via an Escherichia coli expression system and incorporated it into nanodiscs (NDs). These hCB1R-NDs were then immobilized on a single-walled carbon nanotube field-effect transistor (swCNT-FET) to construct a bioelectronic sensing platform. This novel system can sensitively detect the cannabinoid ligand anandamide (AEA) at concentrations as low as 1 fM, demonstrating high selectivity and real-time response. It also successfully identified the hCB1R agonist Δ9-tetrahydrocannabinol and observed that the hCB1R antagonist rimonabant diminished the sensor signal upon AEA binding, indicating the antagonism-based modulation of ligand interaction. Consequently, our bioelectronic sensing platform holds potential for ligand detection and analysis of agonism and antagonism.


Assuntos
Técnicas Biossensoriais , Endocanabinoides , Nanotubos de Carbono , Receptor CB1 de Canabinoide , Humanos , Endocanabinoides/metabolismo , Nanotubos de Carbono/química , Receptor CB1 de Canabinoide/metabolismo , Receptor CB1 de Canabinoide/antagonistas & inibidores , Transistores Eletrônicos , Alcamidas Poli-Insaturadas/química , Alcamidas Poli-Insaturadas/farmacologia , Ácidos Araquidônicos/química , Ácidos Araquidônicos/farmacologia , Canabinoides/metabolismo , Canabinoides/farmacologia , Canabinoides/química , Agonistas de Receptores de Canabinoides/farmacologia , Agonistas de Receptores de Canabinoides/química , Dronabinol/farmacologia , Dronabinol/química , Escherichia coli/efeitos dos fármacos , Escherichia coli/metabolismo
9.
J Neurosci Methods ; 410: 110249, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39151657

RESUMO

BACKGROUND: Accurate real-time eye tracking is crucial in oculomotor system research. While the scleral search coil system is the gold standard, its implantation procedure and bulkiness pose challenges. Camera-based systems are affected by ambient lighting and require high computational and electric power. NEW METHOD: This study presents a novel eye tracker using proximity capacitive sensors made of carbon-nanotube-paper-composite (CPC). These sensors detect femtofarad-level capacitance changes caused by primate corneal movement during horizontal and vertical eye rotations. Data processing and machine learning algorithms are evaluated to enhance the accuracy of gaze angle prediction. RESULTS: The system performance is benchmarked against the scleral coil during smooth pursuits, saccades tracking, and fixations. The eye tracker demonstrates up to 0.97 correlation with the coil in eye tracking and is capable of estimating gaze angle with a median absolute error as low as 0.30°. COMPARISON: The capacitive eye tracker demonstrates good consistency and accuracy in comparison to the gold-standard scleral search coil method. CONCLUSIONS: This lightweight, non-invasive capacitive eye tracker offers potential as an alternative to traditional coil and camera-based systems in oculomotor research and vision science.


Assuntos
Tecnologia de Rastreamento Ocular , Aprendizado de Máquina , Nanotubos de Carbono , Animais , Tecnologia de Rastreamento Ocular/instrumentação , Movimentos Oculares/fisiologia , Macaca mulatta , Masculino , Algoritmos
10.
Nat Commun ; 15(1): 7482, 2024 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-39209826

RESUMO

Carbon nanotube field effect transistors (CNT-FET) hold great promise as next generation miniaturised biosensors. One bottleneck is modelling how proteins, with their distinctive electrostatic surfaces, interact with the CNT-FET to modulate conductance. Using advanced sampling molecular dynamics combined with non-canonical amino acid chemistry, we model protein electrostatic potential imparted on single walled CNTs (SWCNTs). We focus on using ß-lactamase binding protein (BLIP2) as the receptor as it binds the antibiotic degrading enzymes, ß-lactamases (BLs). BLIP2 is attached via the single selected residue to SWCNTs using genetically encoded phenyl azide photochemistry. Our devices detect two different BLs, TEM-1 and KPC-2, with each BL generating distinct conductance profiles due to their differing surface electrostatic profiles. Changes in conductance match the model electrostatic profile sampled by the SWCNTs on BL binding. Thus, our modelling approach combined with residue-specific receptor attachment could provide a general approach for systematic CNT-FET biosensor construction.


Assuntos
Técnicas Biossensoriais , Simulação de Dinâmica Molecular , Nanotubos de Carbono , Eletricidade Estática , beta-Lactamases , Técnicas Biossensoriais/métodos , beta-Lactamases/química , beta-Lactamases/metabolismo , beta-Lactamases/genética , Nanotubos de Carbono/química , Transistores Eletrônicos , Ligação Proteica
11.
J Hazard Mater ; 477: 135358, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39088958

RESUMO

To address the potential hazards of organophosphorus pesticides (OPs) residues in tea, an electrochemiluminescence (ECL) aptasensor based on functionalized nanomaterials was constructed in this work. Firstly, gold nanoparticles (AuNPs) were attached on the surface of multi-walled carbon nanotubes (MWCNTs) by the constant potential electrodeposition to form a compound, and it was utilized to provide excellent immobilization sites for complementary DNA (cDNA). Subsequently, composite nanomaterials were synthesized by a one-pot method with aminated Luminol/silver nanoparticles@silica nanospheres (NH2-Luminol/Ag@SiO2NSs). Finally, NH2-Luminol/Ag@SiO2NSs was combined with a malathion aptamer (Apt) to obtain signal probes (SPs) for the construction of an aptasensor. The aptasensor had a wide linear range (1×10-3-1×103 ng/mL) and a low limit of detection (LOD) (0.3×10-3 ng/mL). It had the virtues of high sensitivity, wonderful stability and excellent specificity, which could be used for the detection of malathion residue in tea. The work provides a proven way for the construction of a rapid and ultrasensitive aptasensor with low-cost.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Eletroquímicas , Ouro , Limite de Detecção , Medições Luminescentes , Luminol , Malation , Nanopartículas Metálicas , Dióxido de Silício , Prata , Chá , Malation/análise , Malation/química , Chá/química , Nanopartículas Metálicas/química , Luminol/química , Prata/química , Técnicas Eletroquímicas/métodos , Medições Luminescentes/métodos , Dióxido de Silício/química , Ouro/química , Aptâmeros de Nucleotídeos/química , Resíduos de Praguicidas/análise , Nanotubos de Carbono/química , Contaminação de Alimentos/análise , Técnicas Biossensoriais/métodos
12.
Biosens Bioelectron ; 263: 116609, 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-39094289

RESUMO

Developing non-passivating and fully integrated electrode arrays for point-of-care testing of carcinoembryonic antigen (CEA) is crucial, as the serum level of CEA is closely associated with colorectal cancer. Herein, we propose a simple, low-cost, and eco-friendly template-assisted filtration method for the scalable preparation of carbon nanotube-bridged Ti3C2Tx MXene (MX@CNT) electrode arrays with a conductive network. Furthermore, we fabricate a homogeneous electrochemical (HEC) sensor for CEA detection by integrating a magnetic-bead-based alkaline phosphatase-linked immunoassay (MB-aElisa), which enables the in-situ generation of the electroactive substance 1-naphthol (1-NP). Benefiting from the unique electrochemical characteristics of a MX@CNT electrode array, such as ultra-low background signal and superior electrocatalytic activity towards the hydrolyzed 1-NP, the MB-aElisa-based HEC sensor specifically measures CEA within a detection range spanning from 0.005 to 1.0 ng mL-1, achieving a detection limit of 1.6 pg mL-1. Subsequently, this biosensing prototype is successfully utilized for the detection of CEA in serum specimens obtained from colorectal cancer patients. More importantly, the integration of MB-aElisa with a MX@CNT electrode array not only marks a significant advancement but also enables the creation of a one-step homogeneous electrochemical immunosensing platform, serving as a paradigm for the highly sensitive and selective measurement of trace tumor markers in complex biological samples.


Assuntos
Biomarcadores Tumorais , Técnicas Biossensoriais , Antígeno Carcinoembrionário , Técnicas Eletroquímicas , Limite de Detecção , Nanotubos de Carbono , Nanotubos de Carbono/química , Humanos , Técnicas Biossensoriais/instrumentação , Antígeno Carcinoembrionário/sangue , Técnicas Eletroquímicas/métodos , Biomarcadores Tumorais/sangue , Imunoensaio/métodos , Imunoensaio/instrumentação , Anticorpos Imobilizados/química , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/sangue , Eletrodos
13.
ACS Appl Mater Interfaces ; 16(33): 43661-43669, 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39106182

RESUMO

This study reports the development of a textile-based colaminar flow hybrid microbial-enzymatic biofuel cell. Shewanella MR-1 was used as a biocatalyst on the anode, and bienzymatic system catalysts based on glucose oxidase and horseradish peroxidase were applied on an air-breathing cathode to address the overpotential loss in a body-friendly way. A single-layer Y-shaped channel configuration with a double-inlet was adopted. Microchannels of biofuel cells were patterned by silk screen printing with Ecoflex to maintain the flexibility of textile substrates without harm to the human body. The electrodes were fabricated with poly(3,4-ethylenedioxythiophene):polystyrene sulfonate and a mixture of multiwalled carbon nanotubes and single-walled carbon nanotubes by screen printing. The effects of electrode materials, catalyst type, catalyst concentration, and glucose concentration in the catholyte were investigated to optimize the fuel cell performance. The peak power density (44.9 µW cm-2) and maximum current density (388.9 µA cm-2) of the optimized hybrid biofuel cell were better than those of previously reported textile- or paper-substrate microscale single microbial fuel cells. The developed biofuel cell will be a useful platform as a microscale power source that is harmless to the environment and living organisms.


Assuntos
Fontes de Energia Bioelétrica , Eletrodos , Glucose Oxidase , Nanotubos de Carbono , Shewanella , Têxteis , Glucose Oxidase/química , Glucose Oxidase/metabolismo , Nanotubos de Carbono/química , Shewanella/enzimologia , Shewanella/metabolismo , Glucose/química , Glucose/metabolismo , Peroxidase do Rábano Silvestre/química , Peroxidase do Rábano Silvestre/metabolismo
14.
Mikrochim Acta ; 191(9): 558, 2024 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-39177820

RESUMO

An innovative supramolecular architecture is reported for bienzymatic glucose biosensing based on the use of a nanohybrid made of multi-walled carbon nanotubes (MWCNTs) non-covalently functionalized with a Schiff base modified with two phenylboronic acid residues (SB-dBA) as platform for the site-specific immobilization of the glycoproteins glucose oxidase (GOx) and horseradish peroxidase (HRP). The analytical signal was obtained from amperometric experiments at - 0.050 V in the presence of 5.0 × 10-4 M hydroquinone as redox mediator. The concentration of GOx and HRP and the interaction time between the enzymes and the nanohybrid MWCNT-SB-dBA deposited at glassy carbon electrodes (GCEs) were optimized through a central composite design (CCD)/response surface methodology (RSM). The optimal concentrations of GOx and HRP were 3.0 mg mL-1 and 1.50 mg mL-1, respectively, while the optimum interaction time was 3.0 min. The bienzymatic biosensor presented a sensitivity of (24 ± 2) × 102 µA dL mg-1 ((44 ± 4) × 102 µA M-1), a linear range between 0.06 mg dL-1 and 21.6 mg dL-1 (3.1 µM-1.2 mM) (R2 = 0.9991), and detection and quantification limits of 0.02 mg dL-1 (1.0 µM) and 0.06 mg dL-1 (3.1 µM), respectively. The reproducibility for five sensors prepared with the same MWCNT-SB-dBA nanohybrid was 6.3%, while the reproducibility for sensors prepared with five different nanohybrids and five electrodes each was 7.9%. The GCE/MWCNT-SB-dBA/GOx-HRP was successfully used for the quantification of glucose in artificial human urine and commercial human serum samples.


Assuntos
Técnicas Biossensoriais , Ácidos Borônicos , Enzimas Imobilizadas , Glucose Oxidase , Peroxidase do Rábano Silvestre , Nanotubos de Carbono , Bases de Schiff , Nanotubos de Carbono/química , Bases de Schiff/química , Técnicas Biossensoriais/métodos , Ácidos Borônicos/química , Glucose Oxidase/química , Glucose Oxidase/metabolismo , Peroxidase do Rábano Silvestre/química , Peroxidase do Rábano Silvestre/metabolismo , Humanos , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Glucose/análise , Eletrodos , Limite de Detecção , Técnicas Eletroquímicas/métodos , Glicemia/análise
15.
ACS Nano ; 18(34): 22874-22887, 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39148286

RESUMO

Spectral fingerprinting has emerged as a powerful tool that is adept at identifying chemical compounds and deciphering complex interactions within cells and engineered nanomaterials. Using near-infrared (NIR) fluorescence spectral fingerprinting coupled with machine learning techniques, we uncover complex interactions between DNA-functionalized single-walled carbon nanotubes (DNA-SWCNTs) and live macrophage cells, enabling in situ phenotype discrimination. Utilizing Raman microscopy, we showcase statistically higher DNA-SWCNT uptake and a significantly lower defect ratio in M1 macrophages compared to M2 and naive phenotypes. NIR fluorescence data also indicate that distinctive intraendosomal environments of these cell types give rise to significant differences in many optical features, such as emission peak intensities, center wavelengths, and peak intensity ratios. Such features serve as distinctive markers for identifying different macrophage phenotypes. We further use a support vector machine (SVM) model trained on SWCNT fluorescence data to identify M1 and M2 macrophages, achieving an impressive accuracy of >95%. Finally, we observe that the stability of DNA-SWCNT complexes, influenced by DNA sequence length, is a crucial consideration for applications, such as cell phenotyping or mapping intraendosomal microenvironments using AI techniques. Our findings suggest that shorter DNA-sequences like GT6 give rise to more improved model accuracy (>87%) due to increased active interactions of SWCNTs with biomolecules in the endosomal microenvironment. Implications of this research extend to the development of nanomaterial-based platforms for cellular identification, holding promise for potential applications in real time monitoring of in vivo cellular differentiation.


Assuntos
DNA , Aprendizado de Máquina , Macrófagos , Nanotubos de Carbono , Fenótipo , Macrófagos/metabolismo , Macrófagos/citologia , Nanotubos de Carbono/química , Camundongos , Animais , DNA/química , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Células RAW 264.7
16.
Nano Lett ; 24(34): 10510-10518, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39145617

RESUMO

Low-dimensional semiconductor-based field-effect transistor (FET) biosensors are promising for label-free detection of biotargets while facing challenges in mass fabrication of devices and reliable reading of small signals. Here, we construct a reliable technology for mass production of semiconducting carbon nanotube (CNT) film and FET biosensors. High-uniformity randomly oriented CNT films were prepared through an improved immersion coating technique, and then, CNT FETs were fabricated with coefficient of performance variations within 6% on 4-in. wafers (within 9% interwafer) based on an industrial standard-level process. The CNT FET-based ion sensors demonstrated threshold voltage standard deviations within 5.1 mV at each ion concentration, enabling direct reading of the concentration information based on the drain current. By integrating bioprobes, we achieved detection of biosignals as low as 100 aM through a plug-and-play portable detection system. The reliable technology will contribute to commercial applications of CNT FET biosensors, especially in point-of-care tests.


Assuntos
Técnicas Biossensoriais , Nanotubos de Carbono , Transistores Eletrônicos , Nanotubos de Carbono/química , Técnicas Biossensoriais/instrumentação , Sistemas Automatizados de Assistência Junto ao Leito , Testes Imediatos , Nanotecnologia/instrumentação , Desenho de Equipamento
17.
Sensors (Basel) ; 24(15)2024 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-39123940

RESUMO

Physical therapy is often essential for complete recovery after injury. However, a significant population of patients fail to adhere to prescribed exercise regimens. Lack of motivation and inconsistent in-person visits to physical therapy are major contributing factors to suboptimal exercise adherence, slowing the recovery process. With the advancement of virtual reality (VR), researchers have developed remote virtual rehabilitation systems with sensors such as inertial measurement units. A functional garment with an integrated wearable sensor can also be used for real-time sensory feedback in VR-based therapeutic exercise and offers affordable remote rehabilitation to patients. Sensors integrated into wearable garments offer the potential for a quantitative range of motion measurements during VR rehabilitation. In this research, we developed and validated a carbon nanocomposite-coated knit fabric-based sensor worn on a compression sleeve that can be integrated with upper-extremity virtual rehabilitation systems. The sensor was created by coating a commercially available weft knitted fabric consisting of polyester, nylon, and elastane fibers. A thin carbon nanotube composite coating applied to the fibers makes the fabric electrically conductive and functions as a piezoresistive sensor. The nanocomposite sensor, which is soft to the touch and breathable, demonstrated high sensitivity to stretching deformations, with an average gauge factor of ~35 in the warp direction of the fabric sensor. Multiple tests are performed with a Kinarm end point robot to validate the sensor for repeatable response with a change in elbow joint angle. A task was also created in a VR environment and replicated by the Kinarm. The wearable sensor can measure the change in elbow angle with more than 90% accuracy while performing these tasks, and the sensor shows a proportional resistance change with varying joint angles while performing different exercises. The potential use of wearable sensors in at-home virtual therapy/exercise was demonstrated using a Meta Quest 2 VR system with a virtual exercise program to show the potential for at-home measurements.


Assuntos
Articulação do Cotovelo , Nanocompostos , Realidade Virtual , Dispositivos Eletrônicos Vestíveis , Humanos , Nanocompostos/química , Articulação do Cotovelo/fisiologia , Robótica/instrumentação , Nanotubos de Carbono/química , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Amplitude de Movimento Articular/fisiologia , Carbono/química
18.
J Chem Inf Model ; 64(16): 6610-6622, 2024 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-39150098

RESUMO

Protein conformations in cells are not solely determined by amino acid sequences; they also depend on cellular environments. For instance, the ribosome tunnel induces its specific α-helix formation during cotranslational folding. Owing to the link between these temporally α-helix and biological functions, the mechanism of α-helix formation inside the ribosome tunnel has been previously explored. Consequently, the conformational restrictions of the tunnel were considered one of the driving forces of α-helix formation. Conversely, the ribosomal tunnel environment, including its chemical properties, appears to influence the α-helix formation. However, a comprehensive analysis of the ribosome tunnel environment's impact on the α-helix formation has not been conducted yet due to challenges in experimentally controlling it. Therefore, as a new computational approach, we proposed a ribosome environment-mimicking model (REMM) based on the radius and components of the experimentally determined ribosome tunnel structures. Using REMM, we assessed the impact of the ribosome tunnel environment on α-helix formation. Herein, we employed carbon nanotubes (CNT) as a reference model alongside REMM because CNT reproduce conformational restrictions rather than the ribosome tunnel environment. Quantitatively, the ability to reproduce the α-helix of nascent peptides in the experimental structure was compared between the CNT and REMM using enhanced all-atom molecular dynamics simulations. Consequently, the REMM more accurately reproduced the α-helix of the nascent peptides than the CNT, highlighting the significance of the ribosome tunnel environment in α-helix formation. Additionally, we analyzed the properties of the peptide inside each model to reveal the mechanism of ribosome tunnel-specific α-helix formation. Consequently, we revealed that the chemical diversities of the tunnel are essential for the formation of backbone-to-backbone hydrogen bonds in the peptides. In conclusion, the ribosome tunnel environment, with the diverse chemical properties, drives its specific α-helix formation. By proposing REMM, we newly provide the technical basis for investigating the protein conformations in various cellular environments.


Assuntos
Biossíntese de Proteínas , Conformação Proteica em alfa-Hélice , Dobramento de Proteína , Ribossomos , Ribossomos/metabolismo , Ribossomos/química , Nanotubos de Carbono/química , Simulação de Dinâmica Molecular , Modelos Moleculares
19.
PLoS One ; 19(8): e0308207, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39110684

RESUMO

Neurofibromatosis Type 1 (NF1) is a complex genetic disorder characterized by the development of benign neurofibromas, which can cause significant morbidity in affected individuals. While the molecular mechanisms underlying NF1 pathogenesis have been extensively studied, the development of effective therapeutic strategies remains a challenge. This paper presents the development and validation of a novel biomaterial testing model to enhance our understanding of NF1 pathophysiology, disease mechanisms and evaluate potential therapeutic interventions. Our long-term goal is to develop an invitro model of NF1 to evaluate drug targets. We have developed an in vitro system to test the cellular behavior of NF1 patient derived cells on electroconductive aligned nanofibrous biomaterials with electrical stimulatory cues. We hypothesized that cells cultured on electroconductive biomaterial will undergo morphological changes and variations in cell proliferation that could be further enhanced with the combination of exogenous electrical stimulation (ES). In this study, we developed electrospun Hyaluronic Acid-Carbon Nanotube (HA-CNT) nanofiber scaffolds to mimic the axon's topographical and bioelectrical cues that influence neurofibroma growth and development. The cellular behavior was qualitatively and quantitively analyzed through immunofluorescent stains, Alamar blue assays and ELISA assays. Schwann cells from NF1 patients appear to have lost their ability to respond to electrical stimulation in the development and regeneration range, which was seen through changes in morphology, proliferation and NGF release. Without stimulation, the conductive material enhances NF1 SC behavior. Wild-type SC respond to electrical stimulation with increased cell proliferation and NGF release. Using this system, we can better understand the interaction between axons and SC that lead to tumor formation, homeostasis and regeneration.


Assuntos
Proliferação de Células , Estimulação Elétrica , Ácido Hialurônico , Nanotubos de Carbono , Células de Schwann , Células de Schwann/metabolismo , Nanotubos de Carbono/química , Humanos , Ácido Hialurônico/química , Nanofibras/química , Neurofibromatose 1/patologia , Neurofibromatose 1/metabolismo , Alicerces Teciduais/química , Células Cultivadas , Materiais Biocompatíveis/química
20.
Int J Biol Macromol ; 276(Pt 1): 133927, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39025191

RESUMO

As is well known, cellulose, as a natural polymer material with abundant reserves, plays an irreplaceable role as the major raw material in energy and chemical-related fields. With the continuous advancement of technology, native single-component cellulose is often unsatisfactory for practical applications, constructing composites is an effective means of expanding the applications. When compounded with other ingredients to prepare composites, cellulose usually needs to be dissolved and regenerated to obtain good dispersion. Current studies have revealed that cellulose is insoluble in conventional solvents, and the limited types of solvent systems that can dissolve cellulose tend to degrade the cellulose during the dissolution process, altering the cellulose properties. Ionic liquids (ILs) are a class of solvents that are capable of dissolving cellulose without adversely affecting the cellulose during the dissolution process, such as degradation. Graphene and carbon nanotubes (CNTs) are poorly dispersed and easily agglomerated by π-π stacking in general solvents, whereas ILs can effectively shield them from π-π stacking, resulting in a favorable and steady dispersion. Thus, the cellulose composites of graphene/CNTs can be prepared with the assistance of ILs. In this paper, the solubilization of cellulose by ILs and the solubilization mechanism to the preparation of cellulose composites with graphene/CNTs are reviewed, the interactions between graphene, CNTs and cellulose in the composites are elucidated, and the preparation of cellulose composites with graphene/CNTs is introduced in terms of their structure, properties and application potential.


Assuntos
Celulose , Grafite , Líquidos Iônicos , Nanotubos de Carbono , Líquidos Iônicos/química , Celulose/química , Nanotubos de Carbono/química , Grafite/química , Solventes/química , Nanocompostos/química , Solubilidade
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