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Since acetone has more medical and industrial applications, its detection plays a significant role in indirectly measuring some quantities and controlling human safety in medical and industrial areas. In this research, a surface plasmon resonance image sensor was developed based on chitosan, poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS), and gold nanoparticles for the detection of acetone. The gold nanoparticles have been fabricated using the laser ablation technique, and chitosan-PEDOT: PSS and chitosan-PEDOT: PSS-gold-nanoparticles composite were used to detect the pure acetone vapor form using a surface plasmon resonance image sensor. The response of the sensor was compared with the sensor’s response when acetone was mixed with methanol and ethanol. Consequently, the sensor’s response to pure acetone was greater than the sensor’s response in the presence of methanol or ethanol. The sensor’s response is very insignificant when the sensing layer is contacted with pure methanol and ethanol.

In this work, the effect of the simulated body fluid temperature on the electrical interface parameters of the state‐of‐the‐art PEDOT‐PSS electrode was studied. PEDOT‐PSS was synthesized by electrodeposition on graphite and gold‐coated‐graphite electrodes. All electrochemical measurements were performed in phosphate‐buffered saline aqueous solution (pH 7.4) at room temperature (25 °C) and body temperature (37 °C). The results of the work confirmed that the modification of the carbon or metallic electrode with conducting polymer PEDOT : PSS significantly reduced the interfacial impedance and improved charge storage capacity and current injection limit due to its high electroactive surface area, roughness and porosity compared to the bare substrates. The work showed that solution temperature is a critical factor that can influence the electrical interface parameters of electrodes for neural stimulation. Understanding and controlling these temperature‐dependent effects are essential for ensuring the reliability, safety, and efficacy of neural stimulation applications in both research and clinical settings. The work presents whether and to what extent the change in the solution temperature affected the electrical interface parameters of PEDOT‐PSS‐based carbon or gold electrode. Wrong selection of the temperature may introduce large errors, especially when the electrode will be further transferred to the in‐vitro/in‐vivo studies.

Conducting polymers have received much attention recently as organic thermoelectric materials, because of such advantages as plentiful resources, easy synthesis, easy processing, low cost, low thermal conductivity, and easy fabrication of flexible, light, and printable devices with large area. Many reports on organic thermoelectric materials have recently been published. We have studied conducting polymers as organic thermoelectric materials since 1999. During these investigations, we found that the thermal conductivity of conducting polymers did not increase even though electrical conductivity increased; this was a major advantage of conducting polymers as organic thermoelectric materials. We also observed that molecular alignment was one of the most important factors for improvement of the thermoelectric performance of conducting polymers. Stretching of conducting polymers or their precursors was one of the most common techniques used to achieve good molecular alignment. Recently, alignment of the clusters of conducting polymers by treatment with solvents has been proposed as a means of achieving high electrical conductivity. Hybridization of conducting polymers with inorganic nanoparticles has also been found to improve thermoelectric performance. Here we present a brief history and discuss recent progress of research on conducting polymers as organic thermoelectric materials, and describe the techniques used to improve thermoelectric performance by treatment of conducting polymers with solvents and hybridization of conducting polymers with Bi 2 Te 3 and gold nanoparticles.

UV sensors in wearables help outdoor users protect their skin by monitoring exposure. Detecting UV light is crucial for safety, given its potential hazards. Our research has developed an efficient methodology for creating UV sensors. This method is characterized by a streamlined, one-step solution-processed approach, prioritizing simplicity in fabrication, heightened responsiveness, and cost-effectiveness as key attributes. We designed a platform utilizing the synergistic effects of a hybrid network, incorporating the conducting polymer poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT: PSS) and Zinc oxide (ZnO) low dimensional rods (LDR) at varying concentrations of ZnO relative to PEDOT: PSS. Using a straightforward drop-cast technique, the hybrid film was applied to a p-type silicon wafer. Incorporating ZnO LDR into PEDOT: PSS causes the LDR to become integrated into the polymer matrix, ultimately resulting in a consistently distributed film. A thickness profilometer was utilized to measure the thickness of the hybrid film, which was around 1.4 μm. FE-SEM was employed to elucidate the intricate morphological features of ZnO LDR and to investigate the synergistic hybrid composition formed by the combination of PEDOT: PSS and ZnO. The micrographs provided valuable insights into the size, shape, and distribution of ZnO LDR, facilitating a comprehensive understanding of their morphological characteristics. The length of the LDR, on average, was roughly 9.5 μm, and their diameter was approximately 0.575 μm. Furthermore, the formation of the hybrid film was verified using UV-Vis spectroscopy, revealing distinct bands originating from both PSS in PEDOT: PSS and ZnO. Upon UV radiation exposure to the hybrid film, conductivity changes were measured in both UV on and off conditions. The most successful device with 10 wt% of ZnO in PEDOT: PSS exhibited a response of around 7.5%.

This paper presents the feasibility of a fully inkjet-printed, microwave flexible gas sensor based on a resonant electromagnetic transducer in microstrip technology and the impact of the printing process that affects the characteristics of the gas sensor. The sensor is fabricated using silver ink and multi-wall carbon nanotubes (MWCNTs) embedded in poly (3,4-ethylenedioxythiophene) polystyrene (PEDOT: PSS-MWCNTs) as sensitive material for Volatile Organic Compounds (VOCs) detection. Particular attention is paid to the characterization of the printed materials and the paper substrate. The manufacturing process results in a change in relative permittivity of the paper substrate by nearly 20%. Electrical characterization, made in the presence of gas, validates our theoretical approach and the radiofrequency (RF) gas sensor proof of concept.

Herein, a nanocomposite of Poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate)/reduced graphene oxide (PEDOT:PSS/rGO) has been synthesized and modified with L-Cysteine (CySH) peptide in order to reveal the selective and sensitive determination of lead Pb(II) ions using electrochemical modality in the range of concentration 1–70 ppb. The PEDOT-PSS/rGO/CySH nanocomposite was characterized with X-ray diffraction (XRD), Raman spectroscopy, atomic force microscopy (AFM), and electrochemical characterizations. Further, the electrochemical sensor was designed on glassy carbon electrode as PEDOT-PSS/rGO/CySH@GCE as an electroactive material which exhibited highly selective and sensitive sensing response for Pb(II) ions sensing. The limit of detection for Pb(II) was found to be 0.09 ppb, which is significantly better than the maximum Pb contamination limit in potable water (48 nM (10 parts per billion) advised by World Health Organization (WHO) and earlier reported studies as well.

Herein, we present for the first time a novel potentiometric sensor based on the stimulus-responsive molecularly imprinted polymer (MIP) as a selective receptor for neutral dopamine determination. This smart receptor can change its capabilities to recognize according to external environmental stimuli. Therefore, MIP-binding sites can be regenerated in the polymeric membrane by stimulating with stimulus after each measurement. Based on this effect, reversible detection of the analyte via potentiometric transduction can be achieved. MIPs based on 4-vinylphenylboronic acid as the functional monomer were prepared as the selective receptor. This monomer can successfully bind to dopamine via covalent binding and forming a five- or six-membered cyclic ester in a weakly alkaline aqueous solution. In acidic medium, the produced ester dissociates and regenerates new binding sites in the polymeric membrane. The proposed smart sensor exhibited fast response and good sensitivity towards dopamine with a limit of detection 0.15 µM over the linear range 0.2–10 µM. The selectivity pattern of the proposed ISEs was also evaluated and revealed an enhanced selectivity towards dopamine over several phenolic compounds. Constant-current chronopotentiometry is used for evaluating the short-term potential stability of the proposed ISEs. The obtained results confirm that the stimulus-responsive MIPs provide an attractive way towards reversible MIP-based electrochemical sensors designation.

Bone healing can be significantly expedited by applying electrical stimuli in the injured region. Therefore, a three-dimensional (3D) ceramic conductive tissue engineering scaffold for large bone defects that can locally deliver the electrical stimuli is highly desired. In the present study, 3D conductive scaffolds were prepared by employing a biocompatible conductive polymer, ie, poly(3,4-ethylenedioxythiophene) poly(4-styrene sulfonate) (PEDOT:PSS), in the optimized nanocomposite of gelatin and bioactive glass. For in vitro analysis, adult human mesenchymal stem cells were seeded in the scaffolds. Material characterizations using hydrogen-1 nuclear magnetic resonance, in vitro degradation, as well as thermal and mechanical analysis showed that incorporation of PEDOT:PSS increased the physiochemical stability of the composite, resulting in improved mechanical properties and biodegradation resistance. The outcomes indicate that PEDOT:PSS and polypeptide chains have close interaction, most likely by forming salt bridges between arginine side chains and sulfonate groups. The morphology of the scaffolds and cultured human mesenchymal stem cells were observed and analyzed via scanning electron microscope, micro-computed tomography, and confocal fluorescent microscope. Increasing the concentration of the conductive polymer in the scaffold enhanced the cell viability, indicating the improved microstructure of the scaffolds or boosted electrical signaling among cells. These results show that these conductive scaffolds are not only structurally more favorable for bone tissue engineering, but also can be a step forward in combining the tissue engineering techniques with the method of enhancing the bone healing by electrical stimuli.

A comparison of the structure and sensitivity of humidity sensors prepared from graphene (G)-PEDOT: PSS (poly (3,4-ethylenedioxythiophene)) composite material on flexible and solid substrates is performed. Upon an increase in humidity, the G: PEDOT: PSS composite films ensure a response (a linear increase in resistance versus humidity) up to 220% without restrictions typical of sensors fabricated from PEDOT: PSS. It was found that the response of the examined sensors depends not only on the composition of the layer and on its thickness but, also, on the substrate used. The capability of flexible substrates to absorb the liquid component of the ink used to print the sensors markedly alters the structure of the film, making it more porous; as a result, the response to moisture increases. However, in the case of using paper, a hysteresis of resistance occurs during an increase or decrease of humidity; that hysteresis is associated with the capability of such substrates to absorb moisture and transfer it to the sensing layer of the sensor. A study of the properties of G: PEDOT: PSS films and test device structures under deformation showed that when the G: PEDOT: PSS films or structures are bent to a bending radius of 3 mm (1.5% strain), the properties of those films and structures remain unchanged. This result makes the composite humidity sensors based on G: PEDOT: PSS films promising devices for use in flexible and printed electronics.

There is a growing desire for wearable sensors in health applications. Fibers are inherently flexible and as such can be used as the electrodes of flexible sensors. Fiber-based electrodes are an ideal format to allow incorporation into fabrics and clothing and for use in wearable devices. Electrically conducting fibers were produced from a dispersion of poly (3,4-ethylenedioxythiophene)-poly (styrenesulfonate) (PEDOT: PSS). Fibers were wet spun from two PEDOT: PSS sources, in three fiber diameters. The effect of three different chemical treatments on the fibers were investigated and compared. Short 5 min treatment times with dimethyl sulfoxide (DMSO) on 20 μm fibers produced from Clevios PH1000 were found to produce the best overall treatment. Up to a six-fold increase in electrical conductivity was achieved, reaching 800 S cm−1, with no loss of mechanical strength (150 MPa). With a pH-sensitive polyaniline coating, these fibers displayed a Nernstian response across a pH range of 3.0 to 7.0, which covers the physiologically critical pH range for skin. These results provide opportunities for future wearable, fiber-based sensors including real-time, on-body pH sensing to monitor skin disease.