Acetate Nanofibers Research Articles

Innovative upcycling cigarette filters into high-performance cellulose nanofiber-epoxy composites

This research introduces a novel upcycling method for transforming cigarette filters—an abundant and persistent environmental waste—into high-performance epoxy composites reinforced with cellulose nanofibers. The innovation lies in extracting cellulose acetate nanofibers from used cigarette butts via a multi-step purification and electrospinning process, followed by their conversion into regenerated cellulose nanofibers through alkaline hydrolysis. This dual-fiber approach allows us to fabricate four distinct epoxy composites, each reinforced by different nanofiber types: recycled cellulose acetate nanofibers, regenerated cellulose nanofibers from recycled cigarette filters, and their commercial counterparts. Notably, this is the first time regenerated nanofibers derived from waste cigarette filters have been utilized for epoxy composite reinforcement, demonstrating a sustainable, high-value use for a major pollutant. Comprehensive characterizations, including FTIR, XRD, SEM, and contact angle measurements, confirmed the successful regeneration of cellulose nanofibers, showing improved hydrophilicity, reduced crystallinity, and uniform nanofiber morphology with diameters between 200 and 300 nm. The innovation further extends to the mechanical performance of these composites: tensile tests revealed that those reinforced with regenerated cellulose nanofibers exhibited superior tensile strength (49.5–53.8 MPa), significantly outperforming both cellulose acetate nanofiber composites (40.1–42.6 MPa) and neat epoxy resin (31.4 MPa). This marked improvement is attributed to enhanced nanofiber dispersion and interfacial adhesion within the epoxy matrix, an essential advancement over traditional composites. In addition, thermal analysis showed that all composites maintained thermal stability in the 300–400 °C range, comparable to commercial alternatives. The regenerated nanofiber-reinforced composites also displayed enhanced optical transparency due to reduced light scattering, making them ideal candidates for applications requiring both mechanical strength and optical clarity. By pioneering the use of cigarette filter waste for fabricating advanced cellulose nanofiber composites, this study presents an eco-friendly approach to addressing environmental pollution while creating sustainable materials with superior mechanical, thermal, and optical properties.

Enhancing mechanical properties of cellulose acetate/carbon black nanofibers for oil spill cleanup

Oil contamination caused by various oil-related industries and domestic usage is one of the major global challenges that threaten the environment. Therefore, employing efficient and environmentally friendly methods for oil removal from oily water is crucial. Nanofibers offer suitable mediums for such applications due to their low fiber diameter and high surface area. Herein, mechanically enhanced carbon black (CB) loaded-cellulose acetate (CA) nanofiber mats were developed for oil removal applications. Initially, CA/CB nanofibers were fabricated from 15% wt. CA solutions containing 2% wt. CB. To improve the mechanical properties, the samples were treated in an ethanol:acetone bath for 2 and 4h. Increasing post-treatment duration increased the nanofiber diameters from 438 nm to 601 nm and decreased porosities from 75% to 66%. The post-treatments improved the mechanical properties of the samples and the highest modulus was achieved as 20.85 MPa. The water and oil contact angles increased from 86° to 102° and 61° to 80°, respectively. The liquid absorption and retention capacities of the samples were evaluated by immersing them in water, seawater, waste oil, and their emulsions. Despite their lower initial oil absorption compared to the non-treated one, post-treated samples still retained large amounts of oil at the end of 24 h.

Nanofiber-coated quartz crystal microbalance with chitosan overlay for highly sensitive room temperature ammonia gas sensor

Ammonia is toxic and can pose health risks. Ensuring the safety of individuals working with or around ammonia sensors is crucial, adding complexity to the design and use of such sensors. An ammonia gas sensor by quartz crystal microbalance coated with chitosan-overlaid polyvinyl acetate (PVAc) nanofiber has been studied to have high performance in both sensitivity and selectivity. The scanning electron microscope (SEM) and Fourier-transform infrared (FTIR) spectroscopy were used to analyze the sensing surface, which was the electrospun PVAc nanofiber with chitosan overlay. The nanofiber showed a morphological change and had a more active layer after being overlaid by chitosan. The estimation of PVAc nanofiber thickness on the QCM sensor is (12.0 ± 2.1) µm, measured using a digital microscope. The QCM sensor deposited with PVAc nanofiber only had a sensitivity of 0.076 Hz·ppm−1. It improved to 3.012 Hz·ppm−1 after overlaid with 0.7 wt% chitosan (denoted as PVAc/Ch7 sensor), an increase of 39.6 times. Moreover, the PVAc/Ch7 sensor had a rapid response and recovery times of 9 and 35 s with a very low detection limit of 0.526 ppm. The sensor also exhibited good selectivity toward other analytes. In addition, the sensor also had outstanding in other performances, such as linearity, repeatability, reversibility, and excellent long-term stability. This proposed QCM-based ammonia sensor could be an alternative to analyzing ammonia in various fields.

Antimicrobial and antioxidative electrospun cellulose acetate-essential oils nanofibrous membranes for active food packaging to extend the shelf life of perishable fruits

Food preservation is critical to meeting the growing demand for fresh foods. We construct novel active packaging using active chemicals to extend the shelf life of fresh fruit and vegetables. In our study, we harnessed electrospinning technology to manufacture cellulose acetate nanofibers (CANFs) using natural, highly volatile cinnamon bark oil (CNO) and clove bud oil (CBO). The CNO and CBO loaded electrospun fibers were characterized and applied as active packaging membrane to evaluate the impact on shelf life of fresh grapes and tomatoes. Scanning electron microscopy (SEM), fourier-transform infrared spectroscopy (FT-IR), and gas chromatography–mass spectrometry (GC–MS) analysis indicated a uniform volatile component distribution, average fiber diameters, regulated release kinetics, and substantial antioxidant, and antibacterial activities. The use of 50 % w/w CNO and CBO-loaded CANFs as an active food packaging membrane for a shelf-life study of fresh grapes and tomatoes at 4 °C confirmed the microbiological safety of consumption for 40 days compared to 15 days in control samples, with a lesser reduction in physiochemical properties despite sensory evaluation revealing a shelf-life extension until 30 days.The efficacy and potential benefits of sustainable and effective packaging strategies are highlighted in this study, making it a promising alternative for preserving perishable tomatoes and grapes.

Long-term and high-efficiency capture of Escherichia coli using cellulose acetate nanofiber membrane functionalized with reactive 19 dye and polyhexamethylene biguanide

Cellulose acetate (CA) nanofibers have been popularly applied in various biomedical and textile products. In this work, a textile azo-dye Reactive Green 19 (RG19) was selected to be chemically coupled to the CA nanofiber membrane to form dyed CA nanofiber membrane (namely CA-RG19) and then poly(hexamethylene biguanide) (PHMB) as an antibacterial reagent was physically attached to the dyed CA nanofiber membrane, forming CA-RG19-PHMB nanofiber membrane. The nanofiber membranes were evaluated for their physical and mechanical properties, including functional group analysis, morphological characterization, and thermal stability assessment. To investigate the antibacterial properties of the nanofiber membrane, various concentrations of RG19 dye and PHMB were tested to evaluate the antibacterial efficiency (AE) against Escherichia coli of the membranes. It was found that the CA-RG19-PHMB nanofiber membrane exhibited an AE value of approximately 100 %, with the immobilization concentrations of RG19 dye and PHMB being 373.46 mg/g and 0.333 mg/g, respectively. The CA-RG19-PHMB nanofiber membrane showed 100 % antibacterial efficacy after 10 min against E. coli cells. Furthermore, the storage stability of the CA-RG19-PHMB nanofiber membrane remained at approximately 100 % of its initial antibacterial efficacy after 60 days, and it exhibited excellent antibacterial efficacy after five cycles.

Rhamnus prinoides leaf extract loaded polycaprolactone-cellulose acetate nanofibrous scaffold as potential wound dressing: An in vitro study

Rhamnus prinoides leaf contains carbohydrates, saccharides, phenolic acids, and diterpenes with antibacterial, wound-healing, and anti-inflammatory properties. In this study, Rhamnus prinoides leaf extract was successfully incorporated into polycaprolactone-cellulose acetate (PCL-CA) nanofibers through electrospinning technique for the first time. The mats' morphology, diameter, chemical, and crystalline structure were characterized. The study investigated the mats' antibacterial activity, wound healing, cytotoxicity, drug release behaviour, hydrophilicity, and water absorbency properties. The results revealed that the mats exhibited continuous, smooth, without-beads, and interconnected structures, with average fiber diameters ranging from 385 ± 21 nm to 332 ± 74 nm. The antibacterial effeciency was remarkable against S. aureus and E. coli, achieving bacterial reduction percentages exceeding 99 % at concentrations of 3 % and above against S. aureus and 5 % and above against E. coli. Cytotoxic tests showed low-cytotoxicity up to an extract concentration of 7 %. The extract release increases with an increase in concentration. In vitro wound healing assay, the mats enhanced cell migration to the wound area. Additionally, the incorporation of Rhamnus prinoides significantly improved the hydrophilicity and water absorbency of the nanofibers. Overall, the study highlights the mats' broad antimicrobial and wound healing properties with less cytotoxicity, hydrophilicity, and water absorbency, making them promising for use as wound dressings.

Transdermal fluocinolone acetonide loaded decorated hyalurosomes cellulose acetate/polycaprolactone nanofibers mitigated Freund’s adjuvant-induced rheumatoid arthritis in rats

Abstract Purpose This study aimed to develop a transdermal delivery system for fluocinolone acetonide (FLA), a corticosteroid used in treating inflammatory conditions like rheumatoid arthritis (RA), to overcome the limitations of oral administration, such as poor solubility and bioavailability. Methods FLA-loaded PEG decorated hyalurosomes (FLA-PHs) were fabricated using ethanol injection, incorporating various Brij® surfactants and different amounts of hyaluronic acid (HA) based on a full factorial design. The impact of independent variables, HA amount (mg) (X1) and Brij type (X2) were inspected for entrapment efficiency (EE%), particle size (PS), and zeta potential (ZP). The optimum FLA-PHs were then incorporated into ε-polycaprolactone (PCL) and cellulose acetate (CA) nanofibers to enhance sustained transdermal delivery (FLA-NFs). Results The optimum FLA-PHs exhibited EE% of 83.58 ± 0.69%, PS of 169.00 ± 1.41 nm, and ZP of -22.90 ± 0.14 mV. Morphological assessment of FLA-NFs showed promising results in terms of surface roughness. In a Freund-induced rat model of adjuvant-induced arthritis, transdermal treatment with FLA-NFs significantly improved joint histopathological analyses. Furthermore, it suppressed inflammatory markers such as mTORC1, TNF-α, and NF-κB while upregulating TRIM24 and the anti-inflammatory IL-10. Conclusion FLA-NFs present a promising strategy for enhancing the transdermal delivery of FLA for managing RA, offering potential improvements in efficacy and reduced systemic side effects compared to conventional oral administration.

Enhanced thermoregulation performance of knitted fabrics using phase change material incorporated thermoplastic polyurethane and cellulose acetate nanofibers

Enhanced thermoregulation performance of knitted fabrics using phase change material incorporated thermoplastic polyurethane and cellulose acetate nanofibers

Electrochemical Hg2+ sensor based on electrospun cellulose acetate nanofibers doped with Ag nanoparticles

Mercury (Hg) sensors are critical for environmental monitoring, industrial processes, and public health. They are designed to measure the presence and concentration of mercury ions (Hg2+) in various matrices, including air, water, soil, and biological samples. Mercury in the environment raises concerns due to its toxicity and potential for bioaccumulation. Therefore, this work aims to develop an improved, eco-friendly mercury sensor to address the evolving need for monitoring and control of mercury. The electrochemical sensor for reported here is based on the ability of silver (Ag) to catalyze the reduction of the mercury species Hg2+ to elemental mercury (Hg0), forming an Ag/Hg amalgam. To optimize this sensor, the concentration of silver nanoparticles (AgNPs) on modified nanofibers is determined using differential pulse voltammetry (DPV). Morphological studies and chemical characterization reveal a fiber thickness ranging from 250 to 450 nm and characteristic functional groups, respectively. The sensoŕs analytical performance for detecting Hg2+ concentrations is evaluated through cyclic voltammetry (CV) and DPV in 0.1 M potassium chloride as a supporting electrolyte. The sensor’s detection limit (LOD) for Hg2+ was 0.43 μg/L, with a sensitivity of 0.33 mA/μg/L. In conclusion, the electrochemical sensor exhibits sensitivity and selectivity for Hg2+ detection in the presence of other interfering metal ions, along with eco-friendly and cost-effective features, making it a reliable and practical tool for detecting Hg2+ concentration in water samples.

Cellulose acetate nanofiber modified with polydopamine polymerized MOFs for efficient removal of noxious organic dyes.

The need to effectively remove toxic organic dyes from aquatic systems has become an increasingly critical issue in the recent years. In pursuit of this objective, polydopamine (PDA)-binary ZIF-8/UiO-66 (MOFs) was synthesized and incorporated into cellulose acetate (CA), producing ZIF-8/UiO-66/PDA@CA composite nanofibers under meticulously optimized conditions. The potential of fabricated nanofibers to remove cationic methylene blue (MB) dye was investigated. Various analysis tools including FTIR, XRD, SEM, zeta potential, BET, tensile strength testing, and XPS were employed. Results revealed a substantial leap in tensile strength, with ZIF-8/UiO-66/PDA@CA registering an impressive 2.8MPa, as a marked improvement over the neat CA nanofibers (1.1MPa). ZIF-8/UiO-66/PDA@CA nanofibers exhibit an outstanding adsorption capacity of 82mg/g, notably outperforming the 22.4mg/g capacity of neat CA nanofibers. In binary dye systems, these nanofibers exhibit a striking maximum adsorption capacity of 108mg/g, establishing their eminence in addressing the complexities of wastewater treatment. Furthermore, the adsorption data fitted to the Langmuir isotherm, and the pseudo-second-order kinetic model. The fabricated nanofiber demonstrates good reproducibility and durability, consistently upholding its performance over five cycles. This suite of remarkable attributes collectively underscores its potential as a robust, durable, and highly promising solution for the effective and efficient removal of pernicious MB dye, in the context of both water quality improvement and environmental preservation.

Deep Eutectic Solvent Dyeing of Cellulose Acetate Nanofibers with Disperse Dyes: Kinetics, Isotherm, and Thermodynamic Studies

Deep Eutectic Solvent Dyeing of Cellulose Acetate Nanofibers with Disperse Dyes: Kinetics, Isotherm, and Thermodynamic Studies

Boosting the recyclability of flame-made Bi2O3 via insitu immobilization in cellulose acetate nanofibers for efficient photocatalytic degradation of rhodamine B dye

Flame spray pyrolysis is a novel fast-process for producing functional metal oxides. However, these functional nanomaterials are challenged with poor recyclability in water treatment from pollutants such as dyes. Herein, Bi2O3 nanoparticles were produced by flame spray pyrolysis and spun together with eco-friendly cellulose acetate polymer into nanofiber membrane via electrospinning technique. The results reveal that cellulose acetate (CA) has good interaction with the particles, leading to reduced band gap, retardation of fast recombination of carriers and good electron transportation on the surface of the nanofiber membrane. The Bi2O3/CA nanofiber membrane records similar photocatalytic performance to that of flame-made Bi2O3 nanoparticles, that is about 95% dye degradation at 90 min, which was far better than CA and Bi2O3/polyacrylonitrile nanofiber membranes. The electron spin resonance test and free radical scavenger test reveal that abundant hydroxyl radicals serve as the most active species that enhance photocatalytic degradation of dye on Bi2O3/CA nanofiber membrane. The flexible Bi2O3/CA nanofiber membrane also demonstrates easy recyclability after several runs with no significant decline in performance. This study pins the effectiveness of using eco-friendly cellulose acetate in obtaining inorganic-organic composite to concurrently achieve good photocatalytic performance and recyclability.

Early Spoilage Detection of Cultured Pacific White Shrimp Using Quartz Crystal Microbalance Gas Sensors

AbstractIn this study, quartz crystal microbalance (QCM) gas sensors, coated with electrospun polyvinyl acetate (PVAc) nanofibers, were employed to monitor the spoilage level of cultured Pacific white shrimp. The sensors exhibited a sensitivity range of 0.63 to 1.61 Hz/ppm when detecting trimethylamine vapor, a key biomarker for shrimp spoilage. Significant resonance frequency shifts were observed in the as‐prepared sensors when exposed to amine gases released by long‐stored shrimps. These shifts underline the significance of low‐temperature storage for shrimps. While color changes in the shrimps stored at ambient temperature (25 °C) become noticeable to the naked eye after 6 hours, the sensor detects sample deterioration much earlier, registering a prominent frequency shift (178 Hz) within only 3 hours of storage. This outcome suggests the potential of nanofiber‐coated QCM sensors as early‐stage food freshness indicators.

Preparation and Characterization of NPK Nutrient Loaded Electrospun Cellulose Acetate Nanofiber Mat to be used as a Slow-release Fertilizer


 
 
 A major unsolved issue with chemical fertilizers is the low nutrient use efficiency. It has been reported that an excessive amount of up to 70% of the nitrogen applied to plants with traditional fertilizers is lost to the surrounding. Hence, the drastic pollution effects of chemical fertilizer usage. Slow-release fertilizers aim to reduce such losses via slow and sustained release of nutrients to the plant. In this study, we report the successful fabrication and characterization of a novel and biodegradable cellulose acetate (CA) electrospun nanofiber (NF) mat loaded with nitrogen, phosphorus and potassium plant nutrients of urea, hydroxyapatite nanoparticles (HANPs) and MOP respectively to be used as a slow-release fertilizer (SRF). It was envisaged that the unique properties of the electrospun NFs could overcome the shortcomings of traditional slow-release fertilizers (SRFs). The fabrication of the NFs was done with 8.5% w/v CA polymer dissolved in a 6 mL solvent system of acetone to dimethylformamide in a 2:1 volume ratio along with the addition of the aforementioned nutrients at 10% of the polymer weight. Electrospinning parameters were set after parameter optimization. The high-voltage supply was set at 16 kV, the spinneret to collector distance was 13cm and the flow rate was 1.5 ml/h. The solutions were electrospun only when the relative humidity was approximately between 65 to 70%. The HANPs incorporated were synthesized by the wet chemical precipitation method. The successful synthesis of the HANPs was confirmed via Fourier transform infrared (FTIR) spectroscopy and powder X-ray diffraction (PXRD) analysis. The successful loading of the nutrients onto the electrospun NF mat was evident from FTIR, Raman and EDX analysis. Furthermore, the scanning electron microscopy images of the nutrient loaded NFs depicted a reduced average diameter with respect to those of the neat NF mat. The total nitrogen percentage of the nutrient loaded NF mat was determined to be 2.60% from Kjeldahl analysis. The initial nutrient release studies in water depicted a biphasic release model for orthophosphate and potassium nutrients while only a burst release profile was observed for nitrogen. It can be concluded that the electrospun NF mats display a potential application with regards to SRFs. However, several modifications to the NF mat fabrication such as the usage of coaxial electrospinning will have to be made in order to better optimize the nutrient loading and enhance its slow-release properties.
 Keywords: Electrospinning, Nanofiber mat, Slow-release, Hydroxyapatite nanoparticles
 
 

Diabetic wound healing function of PCL/cellulose acetate nanofiber engineered with chitosan/cerium oxide nanoparticles

The use of cerium oxide nanoparticles (CeO2NPs) in diabetic wound repair substances has shown promising results. Therefore, the study was conducted to introduce a novel nano-based wound dressing containing chitosan nanoparticles encapsulated with green synthesized cerium oxide nanoparticles using Thymus vulgaris extract (CeO2-CSNPs). The physical properties and structure of the nanoparticles were analyzed using XRD, DLS, FESEM and FTIR techniques. The electrospun PCL/cellulose acetate-based nanofiber was prepared and CeO2-CSNPs were integrated on the PCL/CA membrane by electrospraying. The physicochemical properties, morphology and biological characteristics of the electrospun nanocomposite were evaluated. The results showed that the nanocomposite with 0.1 % CeO2-CSNPs exhibited high antibacterial performance against S. aureus (<58.59 µg/mL). The PCL/CA/CeO2-CSNPs nanofiber showed significant antioxidant activity up to 89.59 %, cell viability improvement, and cell migration promotion up to 90.3 % after 48 h. The in vivo diabetic wound healing experiment revealed that PCL/CA/CeO2-CSNPs nanofibers can significantly increase the repair rate of diabetic wounds by up to 95.47 % after 15 days. The results of this research suggest that PCL/CA nanofiber mats functionalized with CeO2-CSNPs have the potential to be highly effective in treating diabetes-related wounds.

Random cellulose acetate nanofibers: a breakthrough for cultivated meat production.

Overcoming the challenge of creating thick, tissue-resembling muscle constructs is paramount in the field of cultivated meat production. This study investigates the remarkable potential of random cellulose acetate nanofibers (CAN) as a transformative scaffold for muscle tissue engineering (MTE), specifically in the context of cultivated meat applications. Through a comparative analysis between random and aligned CAN, utilizing C2C12 and H9c2 myoblasts, we unveil the unparalleled capabilities of random CAN in facilitating muscle differentiation, independent of differentiation media, by exploiting the YAP/TAZ-related mechanotransduction pathway. In addition, we have successfully developed a novel process for stacking cell-loaded CAN sheets, enabling the production of a three-dimensional meat product. C2C12 and H9c2 loaded CAN sheets were stacked (up to four layers) to form a ~300-400 μm thick tissue 2 cm in length, organized in a mesh of uniaxial aligned cells. To further demonstrate the effectiveness of this methodology for cultivated meat purposes, we have generated thick and viable constructs using chicken muscle satellite cells (cSCs) and random CAN. This groundbreaking discovery offers a cost-effective and biomimetic solution for cultivating and differentiating muscle cells, forging a crucial link between tissue engineering and the pursuit of sustainable and affordable cultivated meat production.

Formaldehyde gas sensors based on a quartz crystal microbalance modified with aniline-doped polyvinyl acetate nanofibers.

Real-time detection of formaldehyde in the atmosphere remains challenging. The available gaseous formaldehyde sensing methods offer limited sensitivity, selectivity, and robustness. We modified a quartz crystal microbalance (QCM) system for selective detection of formaldehyde in air. The QCM surface was functionalized with polyvinyl acetate (PVAc) nanofibers and doped with 2, 4, and 6 wt% aniline to improve the selectivity and sensitivity of the sensor. The chemical content and morphological structure of PVAc nanofibers doped with aniline were confirmed by Fourier-transform infrared (FTIR) spectroscopy, energy-dispersive X-ray (EDX) spectroscopy, and scanning electron microscopy (SEM). The results showed that the modified QCM sensor had a sensitivity of 0.056 Hz ppm-1 with a response and recovery times of 200 s and 90 s, respectively. It gave limits of detection (LOD) and limit of quantification (LOQ) of 28 ppm and 96 ppm, respectively. Moreover, the modified QCM was selective towards formaldehyde compared to the other gases. The current workplace exposure limit (WEL) for formaldehyde is 2 ppm, with a time-weighted average over eight hours. Future work will focus on improving the reported QCM sensor to meet the required LOD for formaldehyde detection in the environment and industrial sites.

An ultra-sensitive ammonia sensor based on a quartz crystal microbalance using nanofibers overlaid with carboxylic group-functionalized MWCNTs.

Detecting ammonia at low concentrations is crucial in various fields, including environmental monitoring, industrial processes, and healthcare. This study explores the development and performance of an ultra-sensitive ammonia sensor using carboxylic group-functionalized multi-walled carbon nanotubes (f-MWCNTs) overlaid on polyvinyl acetate nanofibers coated on a quartz crystal microbalance (QCM). The sensor demonstrates high responsiveness, with a frequency shift response of over 120 Hz when exposed to 1.5 ppm ammonia, a sensitivity of 23.3 Hz ppm-1 over a concentration range of 1.5-7.5 ppm, and a detection limit of 50 ppb. Additionally, the sensor exhibits a rapid response time of only 14 s, excellent selectivity against other gases, such as acetic acid, formaldehyde, methanol, ethanol, propanol, benzene, toluene, and xylene, and good stability in daily use. These characteristics make the sensor a promising tool for real-time ammonia detection in diverse applications.

A disposable paper-based electrochemical biosensor decorated by electrospun cellulose acetate nanofibers for highly sensitive bio-detection.

Paper-based electrochemical sensors have the characteristics of flexibility, biocompatibility, environmental protection, low cost, wide availability, and hydropathy, which make them very suitable for the development and application of biological detection. This work proposes electrospun cellulose acetate nanofiber (CA NF)-decorated paper-based screen-printed (PBSP) electrode electrochemical sensors. The CA NFs were directly collected on the PBSP electrode through an electrospinning technique at an optimized voltage of 16 kV for 10 min. The sensor was functionalized with different bio-sensitive materials for detecting different targets, and its sensing capability was evaluated by CV, DPV, and chronoamperometry methods. The test results demonstrated that the CA NFs enhanced the detection sensitivity of the PBSP electrode, and the sensor showed good stability, repeatability, and specificity (p < 0.01, N = 3). The electrochemical sensing of the CA NF-decorated PBSP electrode exhibited a short detection duration of ∼5-7 min and detection ranges of 1 nmol mL-1-100 μmol mL-1, 100 fg mL-1-10 μg mL-1, and 1.5 × 102-106 CFU mL-1 and limits of detection of 0.71 nmol mL-1, 89.1 fg mL-1, and 30 CFU mL-1 for glucose, Ag85B protein, and E. coli O157:H7, respectively. These CA NF-decorated PBSP sensors can be used as a general electrochemical tool to detect, for example, organic substances, proteins, and bacteria, which are expected to achieve point-of-care testing of pathogenic microorganisms and have wide application prospects in biomedicine, clinical diagnosis, environmental monitoring, and food safety.

Investigation of Electrospun Polyacrylonitrile and Cellulose Acetate Smart Nanofibers Doped with Expanded Graphite for the Structure and Photothermal Effect

In this study, photothermal effect by doping expanded graphite (EG) to smart nanofibers produced by electrospinning method was investigated. Fourier transform infrared (FT-IR) spectroscopy was exploited for chemical characterization. Thermal analysis experiments were carried out by heating and cooling curves. Surface morphology of the produced materials was investigated through scanning electron microscope (SEM). Contact angle was determined through contact angle measurement device. The appearance of the peak of the characteristic cyano group in the structure of Polyacrylonitrile (PAN) at 2237.02 cm-1 in the nanofibers having different percentages synthesized with EG and PAN was accepted as the evidence of PAN nanofibers formation. The temperature platforms in the heating/cooling curves exhibited that the temperature of the PAN and cellulose acetate (CA) nanofibers mixed with different EG percentage have higher than pristine nanofibers. The surfaces of the EG@PAN and EG@CA nanofibers were homogeneously distributed fibrous, excessive EG heterogeneously dispersed or electrosprayed in shape. The maximum contacts angles were measured as 67.96° and 52.88° for nanofibers synthesized with EG@CA and EG@PAN, respectively. As the result, the temperature of the nanofibers mixed EG at different percentages increased resulting from having the higher thermal conductivity of EG. Main goal of the study is both investigating photothermal effect in PAN and CA electrospun nanofibers doped with EG of activating heat accumulation property of the produced smart nanofibers for heat energy production from the solar. Thus, it will be possible to develop a new promising method in the production of the smart textile products that have the storage capacity of the solar energy.