Aptamer functionalized cell membrane for brain and nerve cell sensing with high sensitivity and stability.

Accurate dopamine (DA) monitoring with high stability is essential for investigating the chemical basis of brain function and pathology. Electrochemical-based tissue-implantable carbon fiber electrodes (CFEs) show great potential in sensing the dynamics of neurochemicals at a sub-second timescale. However, their anti-fouling property, selectivity, and stability pose challenges. Here, we presented a novel strategy to enhance electrode biocompatibility and stability by modifying CFE with a chitosan (CS) film, brain cell membrane (M), and aptamer cholesterol amphiphiles (DNA-cho). We found that CFE was uniformly covered by a cicada-like membrane after being modified. Electrochemical characterizations indicated that DNA-cho-M-CS-CFE exhibited a wide linear range of DA concentration and showed high sensitivity, specificity, and stability. The electrode also presented excellent fouling resistance and biocompatibility. Moreover, the biosensor was used to detect DA in K+-induced brain slices and PC12 cells with a satisfactory stability and sensitivity and to prove that LPS treatment leads to the delayed and decreased release of DA. DNA-cho-M-CS-CFE showed excellent electrochemical performance and unique advantages for long-term in vivo sensing of living cells, thus providing a new feasible scheme for studying neurochemical kinetics and brain diseases.

Solvothermal In-Situ Synthesis of MIL-53(Fe)@Carbon Felt Photocatalytic Membrane for Rhodamine B Degradation.

In this study, MIL-53(Fe) was innovatively incorporated into carbon felt (CF) by growing in-situ using the solvothermal method. MIL-53(Fe)@carbon felt (MIL-53(Fe)@CF) was prepared and used for the degradation of rhodamine B (RhB). As a new photocatalytic membrane, MIL-53(Fe)@CF photocatalytic membrane has the characteristics of high degradation efficiency and recyclability. Influence of various parameters including MIL-53(Fe)@CF loading, light, electron trapper type, and starting pH on RhB degradation were investigated. The morphology, structure, and degradation properties of MIL-53(Fe)@CF photocatalytic membrane were characterized. Corresponding reaction mechanisms were explored. The results indicated that pH at 4.5 and 1 mmol/L H2O2, 150 mg MIL-53(Fe)@CF could photocatalytically degrade 1 mg/L RhB by 98.8% within 120 min, and the reaction rate constant (k) could reach 0.03635 min-1. The clearance rate of RhB decreased by only 2.8% after three operations. MIL-53(Fe)@CF photocatalytic membrane was found to be stable.

Photo-Fenton self-cleaning carbon fibers membrane supported with Zr-MOF@Fe2O3 for effective phosphate removal from algae-rich water.

Adsorbents featuring abundant binding sites and high affinity to phosphate have been used to resolve water eutrophication. However, most of the developed adsorbents were focused on improving the adsorption ability of phosphate but ignored the effect of biofouling on the adsorption process especially used in the eutrophic water body. Herein, a novel MOF-supported carbon fibers (CFs) membrane with high regeneration and antifouling capability, was prepared by in-situ synthesis of well-dispersed MOF on CFs membrane, to remove phosphate from algae-rich water. The hybrid UiO-66-(OH)2@Fe2O3@CFs membrane exhibits a maximum adsorption capacity of 333.3 mg g-1 (pH 7.0) and excellent selectivity for phosphate sorption over coexisting ions. Moreover, the Fe2O3 nanoparticles anchored on the surface of UiO-66-(OH)2 through 'phenol-Fe(III)' reaction can endow the membrane with the robust photo-Fenton catalytic activity, which improves long-term reusability even under algae-rich condition. After 4 times photo-Fenton regenerations, the regeneration efficiency of the membrane could remain 92.2%, higher than that of hydraulic cleaning (52.6%). Moreover, the growth of C. pyrenoidosa was significantly reduced by 45.8% within 20 days via metabolism inhibition due to membrane-induced P-deficient conditions. Hence, the developed UiO-66-(OH)2@Fe2O3@CFs membrane holds significant prospects for large-scale application in phosphate sequestration of eutrophic water bodies.

Acute Effects of Carbon Fiber Insole on Three Aspects of Sports Performance, Lower Extremity Muscle Activity, and Subjective Comfort.

Carbon fiber insole (CFI), which is lightweight and stiff to reduce energy loss and help wearers perform better in sports, has recently been introduced. However, reports are scarce on the effects of CFI on sports performance, muscle activation, and wearing comfort. This study investigated the acute effects of CFI on sports performance, lower extremity muscle activity, and subjective comfort. Thirty young healthy males with shoe sizes between 260 and 270 mm performed various sports tasks (power generation, agility, and speed) and treadmill runs with wearable sensors under two experimental insole conditions (benchmark insole as a baseline, CFI). The results showed that, compared to the benchmark insole, CFI significantly improved sports performance in terms of power generation (~1.5%) and agility (~1%). However, it activated more of the Tibialis Anterior (~0.7%) and Gastrocnemius Medialis (~0.8%) muscles, and was perceived to be stiffer and less comfortable. These findings suggested that CFI could improve sports performance, but could cause more lower extremity muscle activation and subjective discomfort.

Phosphasilazanes as Inhibitors for Respirable Fiber Fragments Formed during Burning of Carbon-Fiber-Reinforced Epoxy Resins.

Carbon-fiber-reinforced polymer composites (CFRPs) exhibit additional hazards during and after burning due to respirable fragments of thermo-oxidatively decomposed carbon fibers. In this study, various phosphasilazanes are incorporated into the RTM 6 epoxy matrix of a CFRP to investigate their flame-retarding and fiber-protective properties via cone calorimetry. Residual carbon fibers are analyzed using SEM and EDX regarding their diameter and elemental composition of deposits. The decomposition process of phosphasilazanes is characterized by DIP-MS and infrared spectroscopy of char. Flame-retardant efficiency and mode of action are correlated with the chemical structure of the individual phosphasilazane and compared for neat resin and composite samples. Phosphasilazanes mainly acting in the condensed phase show beneficial fiber-protective and flame-retardant properties. Those with additional gas phase activity are less efficient. The phosphasilazanes degrade thermally via scission of the Si-N bond. The distribution and agglomeration of deposited particles, formed during the fire, influence the residual fiber diameters. Continuous layers show the best combination of flame retardancy and fiber protection, as observed for N-dimethylvinylsilyl-amidophosphorus diphenylester.

Adsorption of ionic and neutral pharmaceuticals and endocrine-disrupting chemicals on activated carbon fiber: batch isotherm and modeling studies.

Activated carbon fiber (ACF) has received increasing attention as an adsorbent due to its excellent surface properties. However, the adsorption mechanism of ACF for micropollutants, especially those in ionic forms, has not been sufficiently characterized to date. Therefore, the adsorption property of ACF was characterized using isotherm experiments and linear free energy relationship (LFER). For the experiments, adsorption affinities of thirty-five chemicals, i.e., pharmaceuticals and endocrine-disrupting chemicals, on ACF were estimated. Afterward, the adsorption affinities were used as dependent variables to build the LFER modeling. Finally, three isolated models for each chemical species, i.e., cations, anions, and neutrals, and a comprehensive model for the whole dataset were developed. The LFER results revealed that the models for anionic and neutral compounds have high predictabilities in R2 of 0.97 and 0.96, respectively, while that for cations has a slightly lower R2 of 0.72. In the comprehensive model including cationic, anionic, and neutral compounds, the accuracy of it is 0.81. From the developed LFER model based on the whole dataset, the adsorption mechanisms of ACF for the selected substances could be interpreted, in which the terms of hydrophobic interaction, hydrogen bonding basicity, and anionic Coulombic force of the compounds were identified as the predominant interactions with ACF.

Interfacial Design and Construction of Carbon Fiber Composites by Strongly Bound Hydroxyapatite Nanobelt-Carbon Nanotubes for Biological Applications.

Carbon fiber composites are promising candidates for orthopedic implant applications, which calls for a combination of high mechanical strength and outstanding biotribological properties. In this work, hydroxyapatite nanobelts-carbon nanotubes (HN) were designed and constructed into carbon fiber-anhydrous dicalcium phosphate (DCPA)-epoxy composites (CDE) for simultaneously optimizing the mechanical and biotribological properties via the combined methods of pulse electrochemical deposition and injected chemical vapor deposition. HN provides more nucleation sites for the growth of DCPA and favors the infiltration of epoxy. In addition, HN optimizes the fiber/matrix interface by generating strong interfacial mechanical interlocking. Owing to the synergism of a strongly bound HN, the mechanical and biotribological properties of CDE have demonstrated significant improvement. The tensile strength and elastic modulus of HN-modified CDE (HN-CDE) increase by 52 and 170% compared with CDE, respectively. The wear rate and average friction coefficient of HN-CDE are decreased by 42% and increased by 45% compared with those of CDE, respectively. HN-CDE, with superior mechanical strength and biotribological properties, has high potential as a bone substitute and orthopedic implant.

Comparing the Toxicological Responses of Pulmonary Air-Liquid Interface Models upon Exposure to Differentially Treated Carbon Fibers.

In recent years, the use of carbon fibers (CFs) in various sectors of industry has been increasing. Despite the similarity of CF degradation products to other toxicologically relevant materials such as asbestos fibers and carbon nanotubes, a detailed toxicological evaluation of this class of material has yet to be performed. In this work, we exposed advanced air-liquid interface cell culture models of the human lung to CF. To simulate different stresses applied to CF throughout their life cycle, they were either mechanically (mCF) or thermo-mechanically pre-treated (tmCF). Different aspects of inhalation toxicity as well as their possible time-dependency were monitored. mCFs were found to induce a moderate inflammatory response, whereas tmCF elicited stronger inflammatory as well as apoptotic effects. Furthermore, thermal treatment changed the surface properties of the CF resulting in a presumed adhesion of the cells to the fiber fragments and subsequent cell loss. Triple-cultures encompassing epithelial, macrophage, and fibroblast cells stood out with an exceptionally high inflammatory response. Only a weak genotoxic effect was detected in the form of DNA strand breaks in mono- and co-cultures, with triple-cultures presenting a possible secondary genotoxicity. This work establishes CF fragments as a potentially harmful material and emphasizes the necessity of further toxicological assessment of existing and upcoming advanced CF-containing materials.

Post-explant profiling of subcellular-scale carbon fiber intracortical electrodes and surrounding neurons enables modeling of recorded electrophysiology.

Objective.Characterizing the relationship between neuron spiking and the signals that electrodes record is vital to defining the neural circuits driving brain function and informing clinical brain-machine interface design. However, high electrode biocompatibility and precisely localizing neurons around the electrodes are critical to defining this relationship.Approach.Here, we demonstrate consistent localization of the recording site tips of subcellular-scale (6.8µm diameter) carbon fiber electrodes and the positions of surrounding neurons. We implanted male rats with carbon fiber electrode arrays for 6 or 12+ weeks targeting layer V motor cortex. After explanting the arrays, we immunostained the implant site and localized putative recording site tips with subcellular-cellular resolution. We then 3D segmented neuron somata within a 50µm radius from implanted tips to measure neuron positions and health and compare to healthy cortex with symmetric stereotaxic coordinates.Main results.Immunostaining of astrocyte, microglia, and neuron markers confirmed that overall tissue health was indicative of high biocompatibility near the tips. While neurons near implanted carbon fibers were stretched, their number and distribution were similar to hypothetical fibers placed in healthy contralateral brain. Such similar neuron distributions suggest that these minimally invasive electrodes demonstrate the potential to sample naturalistic neural populations. This motivated the prediction of spikes produced by nearby neurons using a simple point source model fit using recorded electrophysiology and the mean positions of the nearest neurons observed in histology. Comparing spike amplitudes suggests that the radius at which single units can be distinguished from others is near the fourth closest neuron (30.7 ± 4.6µm,X-± S) in layer V motor cortex.Significance.Collectively, these data and simulations provide the first direct evidence that neuron placement in the immediate vicinity of the recording site influences how many spike clusters can be reliably identified by spike sorting.

A portable electrochemical sensing platform for serotonin detection based on surface-modified carbon fiber microelectrodes.

Serotonin (5-HT) is one of the key neurotransmitters in the human body, regulating numerous physiological functions. A disruption in 5-HT homeostasis could result in serious health problems, including neurodegenerative disorders, depression, and 5-HT syndrome. Detection of 5-HT concentrations in biological fluids, such as urine, is a potential solution for early diagnosis of these diseases. In this study, we developed a novel, simple, and low-cost electrochemical sensing platform consisting of a portable workstation with customized electrodes for 5-HT detection in artificial biological fluids. Nafion/carbon nanotubes (CNTs) and electrochemically modified carbon fiber microelectrodes (Nafion-CNT/EC CFMEs) displayed improved 5-HT sensitivity and selectivity. Together with a customized Ag/AgCl reference electrode and Pt counter electrode, the portable 5-HT sensing platform had a sensitivity of 0.074 µA µM-1 and a limit of detection (LOD) of 140 nM. This system was also assessed to measure 5-HT spiked in artificial urine samples, showing nearly full recovery rates. These satisfactory results demonstrated that the portable system exhibits outstanding performance and confirmed the feasibility of 5-HT detection, which can be used to provide point-of-care analysis in actual biological samples.

Hydrogel-Coated Microelectrode Resists Protein Passivation of In Vivo Amperometric Sensors.

Passivation of electrodes caused by nonspecific adsorption of protein can dramatically reduce sensing sensitivity and accuracy, which is a great challenge for in vivo neurochemical monitoring. However, most antipassivation strategies are not suitable to carbon fiber microelectrodes (CFMEs) for in vivo measurement, and these methods also do not work on electrochemical biosensors that fix biometric elements. In this study, we demonstrate that chitosan hydrogel-coated microelectrodes can avoid the current passivation caused by protein adsorption on the surface of carbon fiber because the chitosan hydrogel prepared by local pH gradient caused by hydrogen evolution reaction has three-dimensional networks containing large amounts of water. The highly hydrophilic three-dimensional structure of hydrogel not only forms a biocompatible interface to confine enzymes but also keeps the fast mass transfer of analytes, such as dopamine, ascorbic acid, and glucose. The consistency of the precalibration and postcalibration of the prepared sensor enables in vivo amperometric detection of both electroactive species based on their redox property and electroinactive species based on the enzyme. This study provides a simple and versatile strategy to constitute an amperometric sensor interface to resist passivation of protein adsorption in a complex biological environment such as the brain.

Fe, N, S co-doped cellulose paper carbon fibers as an air-cathode catalyst for microbial fuel cells.

The heteroatoms and transition metal co-doped carbon-based catalysts are an important way to improve the catalytic activity of oxygen reduction reaction (ORR). Herein, we reported a facile method to obtain iron, nitrogen, and sulfur co-doped cellulose paper carbon fibers as catalysts (Fe-N-S/CFs) for ORR in microbial fuel cells (MFCs) with the adsorption recovery of Congo red molecules from dye wastewater. The thermal treatment promoted the etching of carbon surface by ferric ions, resulting in increased surface roughness for forming the defective carbon structure. The rich active species and defective carbon formed on the etched surface to enhance the electroactive surface area and effective sites. Fe-N-S/CFs catalysts achieved high half-wave potential due to the synergy effect between chemical components and defect structures. The assembled single-chamber air cathode MFC gained a high maximum power density of 1773 ± 40 mW m-2 versus Pt/C MFC of 1325 ± 94 mW m-2. This work provides a strategy for recovering dye molecules from wastewater to prepare non-precious metal catalysts for enhancing ORR activity.

Novel 3D carbon fibers derived from Luffa wastes for oil/water separation.

In this study, the 3D structure of carbon fibers (CFs) was prepared from Luffa sponge wastes by H3PO4 impregnation with various ratios and a low-temperature carbonization process at 500 °C in a nitrogen atmosphere. The H3PO4-treated Luffa sponge had higher thermal stability and carbonic yield (∼60-70%) than neat-Luffa (∼21%). Characterization analyses exposed that the synthesized CFs derived from H3PO4-treated Luffa exhibited oleophilic and hydrophobic carbonic nature with 3D sponge skeletal, reflecting an ideal structure for oil sorption. The engine oil sorption properties on the CFs were studied by varying the contact time. The engine oil sorption equilibrium data for 3D CFs samples was explained by the pseudo-second-order and intraparticle diffusion models. The equilibrium oil sorption capacities of 3D CFs were as large as 23.1 ± 0.4 g/g for engine oil, 23.7 ± 1.0 g/g for gasoline, 28.1 ± 1.0 g/g for almond oil, and 29.2 ± 0.8 g/g for pomegranate seed oil in 20 min. Moreover, the optimized 3D CFs can be selectively for oil/water separation applications, such as high capacities for various oils, fast kinetic sorption, and reusability (>6 cycles). This research presented a facile and cost-effective process for the 3D CFs through recycling Luffa sponge wastes for rapid oil sorption.

Applications of Carbon Fiber Instrumentation in Spinal Oncology: Recent Innovations in Spinal Instrumentation and 2-Dimensional Illustrative Operative Video.

BACKGROUND: The management of spinal oncology necessitates a multimodal approach, with surgical intervention, radiation-based therapy, and postoperative advanced imaging. These systems must work well together to provide optimal patient outcomes. Traditional metallic spinal implants produce image artifacts and lead to radiation dose attenuation, which inhibit both disease monitoring and disease treatment, respectively. OBJECTIVE: To demonstrate the feasibility of an improved biomaterial implant that provides structural stability, while also allowing for disease monitoring and treatment in spinal oncology patients. METHODS: From February 2021 to September 2021, 3 patients with spinal oncologic deformity requiring resection and posterior spinal stabilization underwent fixation with polyether ether ketone-carbon fiber implants at a single academic institution. RESULTS: Patient ages ranged from 23 to 74 years (mean: 44.7 years). All patients underwent posterior spinal fixation using standard approaches. They each received polyether ether ketone-carbon fiber pedicle screw and rod implants, placed in standard fashion. There were no dural tears, postoperative wound infections, or other complications related to their treatment. Postoperative surveillance revealed gross total resection of the targeted tumor on postoperative radiographic imaging. CONCLUSION: Polyether ether ketone-carbon fiber implants are a safe and effective option for the treatment of thoracolumbar posterior spinal pathology. The utilization of this novel type of instrumentation in posterior spinal approaches may provide benefit to patients with spinal tumors over existing forms of posterior spinal instrumentation.

Atomic layer deposition (ALD)-constructed TaS2nanoflakes for cancer-related nucleolin detection.

Sensitive detection of nucleolin (NCL) is of great significance for the early diagnosis of cancer. In this work, as a new type of two-dimensional (2D) transition metal dichalcogenides (TMDCs), TaS2nanoflakes (NFs) were precisely constructed by atomic layer deposition (ALD) on carbon fiber paper (CFP) with high specific surface area.In situobservation showed that the nucleation and growth of TaS2nanoflakes were precisely controlled by the number of ALD cycles, thereby regulating their electrochemical properties. The electrochemical performance of TaS2NFs was observed in depth, and compared with that of traditional 2D TMDCs. Due to the high surface area and conductivity, anodic/cathodic current of ∼1570µA of TaS2NFs/CFP can be obtained. Subsequently, an electrochemical biosensor based on ALD-constructed TaS2NFs/CFP for cancer-related NCL detection was fabricated. Due to the excellent electrochemical performance of TaS2NFs/CFP, ultrasensitive detection of NCL in the linear range of 0.1 pM-10 nM with a detection limit of 0.034 pM was achieved.

Optimized porous carbon-fibre microelectrode for multiplexed, highly reproducible and repeatable detection of heavy metals in real water samples.

This work demonstrates the simultaneous identification of four hazardous heavy metals in water samples, namely copper, lead, cadmium, and mercury. A simple yet selective electrode with the simplest fabrication procedure was used. The modified porous carbon threads coated with gold nanoparticles (AuNPs) was employed as a working electrode. The surface chemistry and morphology of the AuNPs deposited porous carbon thread surface were examined. The electrocatalytic activity of the metals on the Au-modified thread surface was observed using the differential pulse voltammetry (DPV) technique. Furthermore, all four metal ions were detected simultaneously, and no interference was observed. Individual and simultaneous experiments to test the impact of concentration revealed that the limit of detection (LoD) was observed to be 1.126 µM, 1.419 µM, 0.966 µM, 0.736 µM for the Cd2+, Pb2+, Cu2+, and Hg2+ metal ions respectively in a linear concentration range of 10-110 µM of each. Subsequently, the study of pH, interference with coexisting metal ions, repeatability study, and stability analysis was also performed. A real sample analysis utilising three different lake water samples is also carried out to further understand the application of the proposed sensor. A good recovery rate is achieved, and the results are reported. This work paves way for the on-field applicability of the present heavy metal detection platform.

SO3H-functionalized carbon fibers for the catalytic transformation of glycerol to glycerol tert-butyl ethers.

Carbon fibers (CFs) of high quality were produced from hydrocarbons such as isobutane or ethylene using the catalytic chemical vapor deposition method (CCVD) and Ni catalyst. The as-prepared samples were functionalized with acidic groups using concentrated sulfuric acid or 4-benzenediazonium sulfonate (BDS) generated in situ from sulfanilic acid and sodium nitrite. The morphological features of the materials were confirmed by transmission electron microscopy, whereas their physicochemical properties were characterized by means of elemental and textural analyses, thermogravimetric (TG) method, Raman spectroscopy, potentiometric back titration, and X-ray diffraction analysis. The obtained CFs were used as catalysts in glycerol etherification with tert-butyl alcohol at 110 °C under autogenous pressure. The BDS-modified CFs were particularly effective in the reaction, showing high glycerol conversions (of about 45-55% after 6 h) and substantial yields of mono- and di-glycerol ethers. It was found that the chemistry of the sample surface was crucial for the process. The high concentration of -SO3H groups decorating CFs boosted the formation of di- and tri-tert-butyl glycerol ethers. Surface oxygen functionalities also had a positive effect on the reaction, however, their impact on the catalytic performances of CFs was significantly weaker compared to that shown by -SO3H groups and it was probably due to the adsorption of reagents on the catalyst surface.

Mechanical adaptations in walking using carbon fiber ankle foot orthoses for patients with peripheral artery disease.

BACKGROUND: The effectiveness of community-based walking programs for patients with peripheral artery disease (PAD) can be limited by calf claudication during exercise. Recent evidence finds adding carbon fiber ankle foot orthoses (AFO) to a walking program can result in improvements in patient mobility and delay claudication onset when walking. RESEARCH QUESTION: How may carbon fiber AFO alter ankle walking mechanics and corresponding triceps surae muscle recruitment in a manner that could improve patient mobility? METHODS: In this repeated measures cohort study, fifteen patients with PAD were fit with bilateral AFO before completing self-paced gait analysis including electromyography. Patients were then given standard advice to walk at home using the devices for 12 weeks. Twelve patients completed follow-up testing. RESULTS: There were no significant interactions between main effects for any variable of interest (p ≥ 0.189). Further, there were no within-subjects main effects for testing time for self-selected gait speed or any of the kinetic or kinematic variables (p ≥ 0.435). There were significant main effects for AFO use with reductions in dorsi flexion (p < 0.001), plantar flexion at toe off (p < 0.001), ankle plantar flexor moment (p = 0.037), and ankle plantar flexor power (p < 0.001). Triceps surae recruitment did not change between AFO conditions (p > 0.05). SIGNIFICANCE: Adding carbon fiber AFO limits peak ankle motion and joint power during self-paced walking for people with PAD while maintaining their walking speed. These gait adaptions were maintained over our 12 weeks of walking practice time. A resulting decrease in plantar flexor power while maintaining gait speed may provide the mechanism by which AFO can delay claudication onset which are major barrier to PAD walking programs. Calf muscle recruitment was maintained when adding the AFO which suggests sufficient muscle exertion could exist to maintain muscle integrity with sustained AFO use.

Synergistic effect of sulfonation followed by precipitation of amorphous calcium phosphate on the bone-bonding strength of carbon fiber reinforced polyetheretherketone.

Sulfonation and applications of amorphous calcium phosphate are known to make polyetheretherketone (PEEK) bioactive. Sulfonation followed by precipitation of amorphous calcium phosphate (AN-treatment) may provide PEEK with further bone-bonding strength. Herein, we prepared a carbon-fiber-reinforced PEEK (CPEEK) with similar tensile strength to cortical bone and a CPEEK subjected to AN-treatment (CPEEK-AN). The effect of AN-treatment on the bone-bonding strength generated at the interface between the rabbit's tibia and a base material was investigated using a detaching test at two time-points (4 and 8 weeks). At 4 weeks, the strength of CPEEK-AN was significantly higher than that of CPEEK due to the direct bonding between the interfaces. Between 4 and 8 weeks, the different bone forming processes showed that, with CPEEK-AN, bone consolidation was achieved, thus improving bone-bonding strength. In contrast, with CPEEK, a new bone was absorbed mainly on the interface, leading to poor strength. These observations were supported by an in vitro study, which showed that pre-osteoblast on CPEEK-AN caused earlier maturation and mineralization of the extracellular matrix than on CPEEK. Consequently, AN-treatment, comprising a combination of two efficient treatments, generated a synergetic effect on the bonding strength of CPEEK.

Flow-through heterogeneous electro-Fenton system using a bifunctional FeOCl/carbon cloth/activated carbon fiber cathode for efficient degradation of trimethoprim at neutral pH.

The synthesis of multifunctional cathode with high-efficiency and stable catalytic activity for simultaneously producing and activating H2O2 is an effective way for promoting the performance of heterogeneous electro-Fenton process (HEF). In addition, accelerating mass transfer by adopting a flow-through reactor is also great importance because of its better utilization of catalysts and adequate contact of the contaminant with the oxidants generated on the electrode surface. Herein, a novel flow-through HEF (FHEF) system was designed for the degradation of trimethoprim (TMP) using bifunctional cathode with a sandwich structure FeOCl nanosheets loaded onto carbon cloth (CC) and activated carbon fiber (ACF) (FeOCl/CC/ACF). The cathode exhibited excellent performance in activating H2O2 for the in-situ generation of hydroxyl radicals (•OH). The electron spin resonance (ESR) measurements and radical quenching tests proved that the high production of •OH in the FHEF process was favorable to the high catalytic efficiency. 25 mg L-1 TMP was entirely degraded after 60 min, with the TOC removal of 62.6% (180 min) at pH 6.8, 9.0 mA cm-2, and flux rate 210 mL min-1. Moreover, the degradation rate still could reach 83% (60 min) after 10 cycles without obvious valence and crystal phase changes. Simultaneously, the current utilization rate has also been greatly enhanced, with an average current efficiency of 69.9% and a low energy consumption of 0.28 kWh kg-1. The reasonable degradation pathways for TMP were proposed based on the UPLC-QTOF-MS/MS results. Finally, the results of toxicological simulation showed a declining trend in the toxicity of the samples during TMP degradation. These results claim that the FeOCl/CC/ACF-FHEF system is an efficient and economical technology for the treatment of organic contaminants in effluents.