Mechanical Properties Of Carbon Nanotubes Research Articles

Characterization and Evaluation of Mechanical Properties of Carbon Nanotube Filler Epoxy Composite

Characterization and Evaluation of Mechanical Properties of Carbon Nanotube Filler Epoxy Composite

Enhancing the Interaction of Carbon Nanotubes by Metal–Organic Decomposition with Improved Mechanical Strength and Ultra-Broadband EMI Shielding Performance

HighlightsA strategy based on metal-organic decomposition is proposed to enhance the tube-tube interactions of carbon nanotubes (CNTs).The robust tube-tube interactions of CNTs enhance both EMI shielding performance and mechanical properties of CNT film.This innovative approach provides an effective way to obtain high-performance CNT film.

Tailored twisted CNT bundle with improved inter-tube slipping performances

The exceptional mechanical properties of carbon nanotubes (CNTs) have encouraged the development of high-performance synthetic fibers in composite materials. To understand the effect of twisting on the mechanical and slipping performances of CNT bundles, molecular dynamics simulation is applied to investigate the tensile performances, failure modes, and pull-out responses of twisted CNT bundles. A molecular model comprising nineteen parallel aligned single-walled carbon nanotubes (SWCNTs) is twisted into bundles at angles of 0°, 10°, and 20°, and further tensile and pull-out simulations are performed. The tensile simulation indicates that compared with the non-twisted CNT bundle showing a tensile strength of about 82 GPa with obvious inter-tube slipping, the 10°-twisted bundle exhibits a tensile strength of approximately 70 GPa with SWCNTs fracture as the main failure mode, which indicates that twisting improves the inter-tube slipping performance without causing excessive strength reduction. Comparatively, when the twisting angle is 20°, no inter-tube slipping is observed and the tensile strength of the CNT bundle is measured to be 55 GPa, which decreases by approximately 32.9 %. The pull-out simulations further reveal that the pull-out forces increase as the twisting angle increases and the weakened bundle strength of twisted bundle is attributed to the repulsive van der Waals forces caused by the reduced distances between inter-tubes. Essentially, twisting is unfavorable for the overall mechanical strength while torsional densification mitigates the inter-tube slipping, which indicates that a trade-off need to be achieved. This paper provides insights into the tensile and slipping performances of twisted CNT bundles and forms a basis for enhancing the assembled CNTs bundle as the next-generation reinforcing phase in composite materials.

Dispersion mechanism of nanoparticles and its role on mechanical, thermal and electrical properties of epoxy nanocomposites - A Review

The combined effect of nano-reinforcements on the mechanical performance of nanocomposites, which are a novel class of epoxy matrix hybrid nanocomposites containing multiwall carbon nanotubes (MWCNT), graphene, and nanodiamonds (NDs), is drawing substantial attention from many research communities. The discussion concentrates on the dispersion techniques adopted for the preparation of epoxy composites containing different types of nanoparticles (3-D fillers, nanofibers, nanotubes, and plate-like fillers). This review paper covers the electrical, thermal, and mechanical properties of carbon nanotubes (CNTs), graphene, and nanodiamond-reinforced epoxy nanocomposites and correlates them with the topographical features, morphology, weight fraction, dispersion state, and surface functionalization of CNTs, graphene, and nanodiamond. This review paper also summarises recent developments in the dispersion method of different carbon nanoparticles in epoxy matrix.

Damage mechanism and mechanical properties of carbon nanotubes induced by He2+ ion irradiation: Molecular dynamics simulations and experiments

Carbon nanotubes (CNTs) are expected to play a pivotal role in future space device applications owing to their exceptional material properties. To ensure the reliability and safety of CNTs in such applications, meticulous assessment and understanding of their structural integrity under ions irradiation is imperative. In this study, the mechanisms of damage to 1–5 wall CNTs caused by the irradiation of He2+ ions in the 1–100 keV energy range were investigated by conducting molecular dynamics (MD) simulations. The mechanisms of damage induced by He2+ ion irradiation exhibited notable distinctions between single-walled carbon nanotubes (SWCNTs) and multi-walled carbon nanotubes (MWCNTs). SWCNTs easily conducted the kinetic energy of the He2+ irradiation out of the CNTs with cascade collisions, thereby reducing the damage they incurred, whereas the interlayer structure of the MWCNTs resulted in the irradiation energy being confined inside the tubes, leading to an increase in defects. The MD simulations revealed the irradiation swelling phenomenon of the MWCNTs in relation to the kinetic energy of irradiation and the cumulative fluence and indicated that swelling occurred simultaneously inward and outward along the radial direction of the CNTs. Irradiation-induced swelling was observed in experiments involving vertical array carbon nanotubes (VACNTs) irradiated with 540 keV He2+ ions. The results from scanning electron microscopy (SEM) and transmission electron microscopy (TEM) characterization, along with the Raman analysis, indicate that the damage observed in CNTs due to He2+ ion irradiation closely resembles the findings obtained through MD simulations. Both experimental and MD simulation studies demonstrated that increasing the dosage of He2+ ion irradiation increased the CNT defects, causing a transition from the ordered graphite structure to amorphous C. Additionally, the compressive mechanical properties and surface adhesion mechanics of the irradiated VACNTs were examined by performing nanoindentation experiments. The tensile mechanical properties of the irradiated CNTs were evaluated using MD simulations. The combined results indicated that high-energy, high-fluence ion irradiation degraded the mechanical properties of the CNTs. This study comprehensively investigated the mechanisms of damage to CNTs under He2+ ion irradiation and the subsequent impacts on the mechanical properties of the CNTs. The findings of this research provide essential insights for comprehending the irradiation responses of CNTs and for designing composite CNT materials with enhanced radiation resistance.

The base versus tip growth mode of carbon nanotubes by catalytic hydrocarbon cracking: Review, challenges and opportunities

Hydrogen gas production using catalytic hydrocarbon cracking on metal nanoparticles has become a vital bridge technology, as this process, unlike the traditional methane-based reforming process, does not co-produce carbon gasses (e.g., CO, CO2). The major benefit of direct catalytic methane cracking using a nanostructured catalyst is the formation of solid carbon in high-value products, such as carbon nanotubes (CNTs) or filaments. This solid carbon can then be removed physically and valorized. However, it is challenging to design a catalyst capable of sustaining its activity after solid carbon has started to deposit and grow, meanwhile preventing the formation of coke. For CNTs, in particular, the base growth mode of CNTs is the desired pathway, as the catalyst can then be regenerated and re-used. If the CNTs are formed under the tip-growth mode, the catalyst particle will be lifted off the support of the regeneration and reusability is lost. Therefore, the study of CNTs growth modes is a vital topic, both experimentally and theoretically, of designing appropriate catalysts. To date, enormous efforts have been made to investigate conditions where the CNTs base growth mode can be maintained during the carbon deposition process. Several possible correlations and mechanisms regarding the base growth mode have been explored and established. Theoretical calculations and numerical simulations across length scales were conducted to investigate the nucleation mechanism and growth of CNTs. Density functional theory (DFT), classical and quantum-based molecular dynamics (MD) and Monte Carlo (MC) simulations were also carried out to study the initial CNT cap formation and its encapsulation during the catalytic hydrocarbon cracking process. A thermodynamics-based nucleation formula of CNTs for both the base and tip growth modes was also established. However, there is still no consensus on what determines the CNT growth modes and what the roles are of the various influencing factors such as the nanoparticle size, the oxidation state of the catalyst, the mechanical properties of CNT, and the catalyst-support interaction. This paper reviews the current status of CNT's growth mechanism development. The benefits and limitations of theory and modeling approaches concerning CNT growth modes are discussed.

Superior crack propagation inhibitory effectiveness of MWCNT reinforced SBS toward improving oil/gas well cement integrity

The brittleness and low cracking resistance of oil- and gas-well cement threaten its integrity, specially under the high stress concentrations at bottom-hole conditions. Fortunately, the excellent mechanical properties of carbon nanotubes and elastomers motivate researchers to utilize them as versatile candidates that can positively modify the breakage behaviors of cement-based materials. Herein, we investigated the hybridization effects of multi-walled carbon nanotubes (MWCNTs) and styrene–butadiene–styrene (SBS) on the mechanical properties and breakage behaviors of oil- and gas-well cements. MWCNTs and SBS were synthesized and then, characterized with a wide range of techniques, signifying successful syntheses of these two materials. Afterward, SBS was dry mixed with cement powder and then added to the aqueous suspension of MWCNT prepared via sonication method. The mechanical testing (e.g., uniaxial, triaxial, and Brazilian tests), numerical simulation, and imaging analysis showed that incorporation of the SBS into the cement matrix promoted the ductility and macro-scale cracking resistance. The introduction of MWCNTs improved the cohesion, micro-scale cracking resistance, and strength properties of the cement matrix. Thereupon, the hybridization of 0.075 wt% of MWCNT and 9 wt% of SBS endowed great mechanical behavior and cracking resistance to the conventional oil-well cement in both micro and macro structures. These specifications can maintain cement’s durability under the critical thermal and mechanical stress concentrations at various bottom hole conditions. This improvement contains the increasing of strain energy, tensile strength, cohesion, and Poisson’s ratio by 219.27%, 141.17%, 750% and 100%, respectively and reducing the elastic modulus by 41.67%. Fourier Transform Infrared Spectroscopy (FTIR) analysis exhibited that these enhancements can be attributed to favorable interactions between MWCNT and SBS in the cement matrix.

Carbon Nanotube Based Broadband Solar Thermal Absorber Coatings

Radiant energy conversion and storage eliminate the mass transfer process induced power output limitation, and open a new vista for energy utilization. An effective system for harvesting radiant energy from both solar and thermal radiation will be beneficial for further radiant energy utilization. On the other hand, space observatory missions require low-reflectivity surfaces/coatings for space-borne instruments, such as seeker telescopes, optical sensors, etc., to minimize stray and reflected light on targeted telescope and baffle materials and construction. The excellent optical, thermal, and mechanical properties of carbon nanotubes (CNTs) make them as ideal coating materials for absorbing the broadband spectrum across UV-Vis-IR regions.In this presentation, Faraday Technology will discuss an innovative electrophoretic deposition (EPD) manufacturing process, based on the use of pulsed electric fields, for controlled, reproducible, scalable deposition of a wide variety of carbon nanotube based coatings across a broad range of substrates, geometries and sizes (Figure 1 a). The effects of waveforms, electrolytes, substrates, etc. on the formation of robust and uniform coating will be discussed in this talk. The optical properties, and environmental survivability of carbon nanotube coatings will be demonstrated via a variety of testing or characterizations. The CNT coatings show the total hemispherical reflection of 0.5% - 1% across UV-Vis to near infrared (NIR) wavebands, which is much lower than the reflectance of the typically used Z306 black paint (Figure 1 b). These CNT coatings also withstood simulated launch conditions vibrational tests, and demonstrated no weight loss and optical degradation. Furthermore, the CNT coatings were evaluated for atomic oxygen erosion resistance in a simulated low earth orbit (LEO) environment, and showed enhanced resilience when compared to Kapton and HOPG. Faraday will also introduce their applications in low-reflective coatings and solar thermal absorbers for radiant energy harvesting and conversion.In summary, a scalable EPD manufacturing process for fabricating carbon nanotube based coatings have been developed at Faraday for the applications in the field of low-reflective coatings and broadband solar thermal absorbers.Acknowledgements: The financial support from NASA SBIR program through contracts No. 80NNSC18P2062 & 80NSSC19C0177, DARPA SBIR program through grant No. W31P4Q-22-C-0014, DOD MDA STTR program through grant No. HQ0147-19-C-7065, and DOD Air Force SBIR program through grant No. FA9550-22-P-0015 are acknowledged. Figure 1

Optimization of electrical and mechanical properties of a single-walled carbon nanotube composite using a three-roll milling method

In this study, the electrical and mechanical properties of carbon nanotube (CNT)/polydimethylsiloxane (PDMS) composites were optimized using a three-roll milling dispersion method. Depending on the number of CNT walls, such as single-walled carbon nanotubes (SWCNTs) and multi-walled carbon nanotubes (MWCNTs), the three-roll milling conditions required to optimize the electrical conductivity of CNT/PDMS composites are quite different. In addition, the mechanical properties of the CNT/PDMS composites depend on the dispersion time. These properties were improved under an appropriate three-roll milling time but gradually deteriorated after excessive processing time. To demonstrate and optimize this phenomenon, various mechanical, electrical, and thermal properties of the CNT/PDMS composites were measured with respect to the type of CNT, milling time, and filler weight fraction. Morphological and structural analyses were also conducted on the CNT fillers and composites after milling.

Effect of induced vacancy defects on the mechanical behavior of wavy single-walled carbon nanotubes

This study utilized molecular dynamics simulations to assess the influence of structural alterations, such as waviness and vacancy defects, on the mechanical properties of carbon nanotubes. This work utilizes the LAMMPS simulation environment to compare models of carbon nanotubes, thus enabling the observation of fracture properties at an atomistic level. A comparative analysis was conducted on pristine straight carbon nanotubes and their wavy and defective counterparts. The study was divided into two stages: the initial stage revealed that straight carbon nanotubes exhibited superior mechanical strength when subjected to tensile loading. However, introducing waviness along the axis of the carbon nanotubes resulted in a significant reduction in strength. Subsequently, in the second stage, vacancy defects were introduced to the carbon nanotube structure, which were quantified by defect densities and plotted against the tensile strength of the carbon nanotubes. This analysis allowed for a deeper understanding of the correlation between the defect density and tensile strength of carbon nanotube structure. Finally, a relationship between the strain energy and temperature variation in carbon nanotubes was established, emphasizing the importance of temperature control in the applications and manufacturing processes of carbon nanotubes. Overall, this study provides valuable insights into the factors that can affect the mechanical properties of carbon nanotubes.

Enhancing the Electrochemical Properties and Processing Techniques of Carbon Nanotubes for Bio pharmacological Applications: A Research Perspective

Compared with other biopharmaceutical technologies, carbon nanotubes not only have unique structure, but also have strong electrochemical properties, which occupy an important position in the fields of chemistry, physics, biopharmaceutics and materials science, and have played an active role in promoting the development of biopharmaceutics and chemical industry in China. Carbon nanotubes (CNTs) are mainly used in the field of biopharmacology for the determination of small biological molecules and drug molecules, the determination of dopamine and thrombin, the determination of high concentrations of ascorbic acid, and the detection of drug formulations. Although carbon nanotubes (CNTs) have many advantages in the field of biopharmaceutics, there are certain limitations that limit the scope of application of carbon tubes, which are mainly the following: one is the high cost of the carbon nanotube material itself and the high technical difficulty of its preparation; the other is that the smooth surface of the material is not conducive to the loading of other particles; finally, although the carbon nanotubes are modified with different groups after treatment, the structure of the material itself is damaged. Finally, although carbon nanotubes are modified with different groups after treatment, their own material structure is destroyed, which reduces their conduction performance. Although the above defects can affect the performance of carbon nanotubes, they can be solved by optimizing the structure of carbon nanotubes, enhancing the plastic mechanical properties of carbon nanotubes and corrosion resistance, in order to give full play to the role of carbon nanotubes in the field of biopharmaceuticals. In this regard, the author briefly analyzes the electrochemical properties of carbon nanotubes in biopharmacology and the application of treatment methods based on relevant literature and work experience, hoping to provide reference value for related scholars and researchers.

Characterization and application of flexible, highly conductive freestanding films of SWCNT and PMMA nanocomposite prepared by facile solution method

The aim of this work was to prepare single-walled carbon nanotube (SWCNT)-embedded polymethyl methacrylate (PMMA) freestanding polymer films and investigate their mechanical and electrical properties. PMMA is widely used in various applications; however, its poor mechanical and electrical properties limit its use. The electrical and mechanical performance of PMMA can be effectively improved by producing nanoparticle-reinforced PMMA composites. Carbon nanotubes (CNTs) are highly attractive nanoparticles used to develop polymer nanocomposite films with novel properties useful for diverse technological applications. The superior electrical and mechanical properties of CNTs can enhance the corresponding properties of the CNT/PMMA nanocomposite. The SWCNT/PMMA nanocomposite films were prepared with a simple sonication technique by employing ethanol and water as solvents. The prepared films were characterized by X-ray diffraction, photoluminescence, Fourier transform infrared spectroscopy, ultraviolet–visible spectroscopy, and scanning electron microscopy analysis to examine the structural, morphological, and optical properties as well as chemical composition of the films. In addition, nanoindentation and current vs. voltage studies were also conducted. Further, the hydrogen evaluation reaction effect of the prepared electrode was evaluated to investigate the catalytic activity of the films. This technologically attractive SWCNT/PMMA nanocomposite freestanding film prepared first time via a simple low-cost technique showed good conductivity, photosensitivity and flexibility with catalytic property.

Carbon nanotube‐based polymer nanocomposites: Evaluation of barrier, hydrophobic, and mechanical properties for aerospace applications

AbstractThe anticorrosive and mechanical properties of carbon nanotubes (CNTs) in epoxy resin (EP) coatings have been improved by the integration of molybdenum disulfide (MoS2) and 3‐aminopropyltrimethoxysilane (APTMS) for surface modification based on CNTs. SEM/EDX, TEM, TGA/XRD, XPS, and XRD techniques were used to characterize the composites for the various formulations, including APTMS/CNTs, CNTs/MoS2, and APTMS/CNTs‐MoS2. By including APTMS/CNTs‐MoS2 composite, the EP coating exhibits improved anticorrosive and mechanical performance, as demonstrated by electrochemical methods and mechanical testing. Superior hydrophobic property of EP‐APTMS/CNTs‐MoS2 is confirmed by its WCA of 167°. Additionally, it was discovered that the EP‐APTMS/CNTs‐MoS2 had a resistance that was significantly larger (17,421 kΩ.cm2) than the plain epoxy (102 kΩ.cm2), and its hardness (1695 MPa), adhesion (19.7 MPa), and tensile (237 MPa) properties all are improved significantly. Therefore, the newly developed EP‐APTMS/CNTs‐MoS2 could act as the vital material for coating AA7475 aluminum alloy used in aerospace applications.

Effects of functionalized CNTs in improving the dielectric, corrosion protection, and mechanical properties of epoxy nanocomposites for automotive/aircraft components

ABSTRACT Excellent mechanical, thermal, electrical, electrochemical, and optical properties can be found in carbon nanotubes (CNTs). The anticorrosive and mechanical properties of CNTs in epoxy resin (EP) coatings have been improved by the integration of zirconium disulfide (ZrS2) and 2-amino−5-(4-methoxyphenyl)−1, 3, 4-thiadiazole (AMPT) for surface modification based on CNTs. The structural, morphological, and dielectric behaviors of the films were characterized for the different formulations of coatings such as EP, EP/CNTs, EP-AMPT/CNTs, EP-CNTs/ZrS2, and EP-AMPT/CNTs-ZrS2 by means of SEM/EDX, TEM, TGA/XRD, XPS, XRD, and contact angle (CA) measurement. As a result, with the addition of only 0.3% AMPT/CNTs-ZrS2, the dielectric constant of EP was increased by 87-fold at 1 Hz. The electrochemical techniques and mechanical testing confirmed that AMPT/CNTs-ZrS2 composite exhibit enhanced anticorrosive and mechanical performance of the EP coating. Superior hydrophobic property of EP-AMPT/CNTs-ZrS2 is confirmed by its WCA of 161º. Furthermore, the resistance of the EP-AMPT/CNTs-ZrS2 was found to be much higher (20.870 MΩ.cm2)] than that of the pure EP (0.112 MΩ.cm2) and the microhardness and tensile strength of EP-AMPT/CNTs-ZrS2 were increased sharply. Therefore, the newly developed EP-AMPT/CNTs-ZrS2 nanocomposite could act as the vital material for coating AA8014 aluminum alloy used in aerospace applications.

An investigation on the effect of Al4C3 on microstructure and mechanical properties of carbon nanotube reinforced aluminum composite

In carbon nanotube (CNT) reinforced metal-matrix composites, a strong interface between CNTs and the matrix is essential for an effective load transfer. Otherwise, the excellent qualities of CNTs would virtually remain unexploited. The aim of this study is to investigate the effect of Al4C3 formation on the mechanical properties of CNT/Al composites. Composite powders were produced through a three-stage process; First, CNTs were sufficiently crushed via high-energy milling of 20 h. Then, the crushed CNTs were ultrasonically mixed with raw CNTs (in an ethanol medium) followed by a wet milling process. Finally, different amounts of the obtained reinforcing agent (0.5, 1, 1.5, 2, and 3 wt.%) were milled with aluminum powders. Composite powders were subsequently consolidated using spark plasma sintering (SPS) process at two different temperatures (500 and 550 °C) For each sample, the amount of carbide was calculated in a semi-quantitative manner using Raman spectroscopy. The results of phase analysis and mechanical-behavior evaluations showed that Al4C3 formation, due to the consumption of highly-activated crushed CNTs, could improve the interface bonding state while maintaining CNTs structural integrity. Moreover, mechanical and wear tests revealed that the optimum properties were obtained for the composite reinforced by 1wt.% processed carbon nanotubes (PCNTs) and SPSed at 550 °C for 10 min. These findings can open up a window toward the realm of design and processing of CNT/Al composites.

Carbon Nanotubes as an Alternative to Copper Wires in Electrical Machines: A Review

The surge in electric vehicles (EVs) and their electrical appliances requires highly efficient, lightweight electrical machines with better performance. However, conventional wire used for electrical machine windings have certain limits to the current requirements. Copper is a commonly used material in electrical windings, and due to its ohmic resistance, it causes 75% of total losses in electrical machines (copper losses). The high mass of the copper results in a bulky system size, and the winding temperature of copper is always maintained at less than 150 °C to preserve the thermal insulation of the electric machine of the windings. On the other hand, carbon nanotubes and carbon nanotube materials have superior electrical conductivity properties and mechanical properties. Carbon nanotubes ensure 100 MS/m of electrical conductivity, which is higher than the copper electrical conductivity of 59.6 MS/m. In the literature, various carbon nanotubes have been studied based on electrical conductivity, temperature co-efficient with resistivity, material thickness and strength, insulation, and efficiency of the materials. Here, we review the electrical and mechanical properties of carbon nanotubes, and carbon nanotube composite materials are reviewed with copper windings for electrical wires.

Molecular dynamics simulation of mechanical properties of carbon nanotube reinforced cellulose.

Cellulose, hemicellulose, and lignin are the major chemical components in wood paper. Various types of wet and dry strength additives are used to enhance the optical and mechanical properties of recycled paper. One of the possible materials is the carbon nanotube. In order to explore the probability of the use of carbon nanotubes as reinforcing materials and to understand how carbon nanotubes affect the mechanical properties of paper, a single-walled carbon nanotube is inserted into a [Formula: see text] cellulose nanocrystal, and its mechanical properties are studied by using energy minimization and molecular dynamics (MD) simulations. During simulations, the crystals are stretched in the axial direction at a constant speed, and stress and strain are computed and recorded at the atomic level. Our results indicate that carbon nanotube can significantly enhance the mechanical properties of paper.

Effects of solid-state interfacial reaction on the mechanical properties of carbon nanotubes reinforced aluminum matrix composites with heterogeneous structure

To overcome strength-ductility trade-off in carbon nanotubes (CNTs) reinforced Al matrix composites, we developed a novel and controllable strategy via a combination of different length of CNTs and fine/coarse-grained matrices. Microstructure analysis showed that Al4C3 nanorods about 100 nm were distributed in the fine grain zone (FGZ), while CNTs of micron length were distributed in the coarse grain zone (CGZ). Different sizes of reinforcements play different strengthening roles, and the bimodal grains can effectively coordinate deformation, thereby achieving a good combination of strength and ductility. Heat treatment does not affect the microstructure of the FGZ, but significantly affect the CNT/Al interface bonding in the CGZ. Heat treatment at an appropriate temperature can further improve the strength of the composite by improving the interface bonding. When the heat treatment temperature is too high, the coarsening of Al4C3 in CGZ will deteriorate the mechanical properties of the composite.

Ensemble Machine Learning approach for evaluating the material characterization of carbon nanotube-reinforced cementitious composites

Time and cost-efficient techniques are essential to avoid extra conventional experimental studies with large data-set for material characterization of composite materials. This study is aimed at providing a correlation between the structural performance and mechanical properties of carbon nano-tubes reinforced cementitious composites through efficient predictive Machine Learning (ML) models. The Flexural (FS) and Compressive (CS) Strength of Carbon Nanotube (CNT)-reinforced composites were predicted based on the data-rich framework provided in the literature. Two different ensembled ML methods including Random Forest (RF) and Gradient Boosting Machine (GBM) were implemented on those data for predicting the CNT-reinforced cement-based composites. Data-set were utilized for training the proposed models through employing SciKit-Learn library in Python, followed by hyper-parameter tuning and k-fold cross-validation method for obtaining an optimum model to predict the target values. It was shown that the CS values predicted by the proposed models were more accurate than the FS counterparts and the developed model of GBM has less sensitivity to the alteration of test data than the proposed RF model. Finally, sensitivity analysis was conducted through Sobol algorithm and the parameters with highest contribution were identified.

(Invited) Cerebrospinal Fluid Leakage Detection with Carbon Nanotube-Based Field-Effect Transistors

Cerebrospinal fluid (CSF) leakage is a life-threatening medical condition that could result in significant morbidity and mortality if left untreated. However, the gold-standard test for confirming CSF leakage by detecting beta2-transferrin (β2-Tf) proteins using gel electrophoresis and Western blot is labor intensive and requires 3–6 hours. Carbon nanotube-based field-effect transistors (NTFET) are promising candidates for point-of-care diagnostic devices, owing to the outstanding electronic and mechanical properties of carbon nanotubes. The use of enriched semiconducting (sc) single-walled carbon nanotubes (SWCNT) significantly improves the performance of NTFET devices and enables label-free protein detection. To demonstrate that sensitive and specific detection of β2-Tf in biological fluids can be achieved by using NTFET biosensor platform, we have developed a three-step strategy for β2-Tf detection using NTFET devices. The three-step strategy for β2-Tf detection includes two steps of affinity chromatography to isolate β2-Tf and a rapid β2-Tf sensing step utilizing a high-purity sc-SWCNT FET device. Three different sensing configurations for the sc-SWCNT FET sensor were investigated for obtaining the optimal β2-Tf sensing results. Compared to current methods for CSF leak diagnosis, such as electrophoresis and imaging methods, our three-step strategy can offer high quality CSF leak detection with a short turnaround time (around 1 hour), easy instrument access and simple operations, which could potentially benefit medical treatment of traumatic brain injury (TBI) patients and other people in need. The versatility of our sensing platform could also open opportunities for point-of-care applications for other disease-related protein detection, as we have recently demonstrated by rapid detection of SARS-CoV-2 antigens for COVID-19 testing.