Enterocin DD14 can inhibit the infection of eukaryotic cells with enveloped viruses.

Bacteriocins are ribosomally synthesized bacterial peptides endowed with antibacterial, antiprotozoal, anticancer and antiviral activities. In the present study, we evaluated the antiviral activities of two bacteriocins, enterocin DD14 (EntDD14) and lacticaseicin 30, against herpes simplex virus type 1 (HSV-1), human coronavirus 229E (HCoV-229E) and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in Vero, Huh7 and Vero E6 cells, respectively. In addition, the interactions of these bacteriocins with the envelope glycoprotein D of HSV-1 and the receptor binding domains of HCoV-229E and SARS-CoV-2 have been computationally evaluated using protein-protein docking and molecular dynamics simulations. HSV-1 replication in Vero cells was inhibited by EntDD14 and, to a lesser extent, by lacticaseicin 30 added to cells after virus inoculation. EntDD14 and lacticaseicin 30 had no apparent antiviral activity against HCoV-229E; however, EntDD14 was able to inhibit SARS-CoV-2 in Vero E6 cells. Further studies are needed to elucidate the antiviral mechanism of these bacteriocins.

Correction: Diamond nanowires modified with poly[3-(pyrrolyl)carboxylic acid] for the immobilization of histidine-tagged peptides.

Correction for 'Diamond nanowires modified with poly[3-(pyrrolyl)carboxylic acid] for the immobilization of histidine-tagged peptides' by Palaniappan Subramanian et al., Analyst, 2014, 139, 4343-4349, https://doi.org/10.1039/C4AN00146J.

Solar-Driven Ammonia Production through Engineering of the Electronic Structure of a Zr-Based MOF.

As a hydrogen carrier and a vital component in fertilizer production, ammonia (NH3) is set to play a crucial role in the planet's future. While its industrial production feeds half of the global population, it uses fossil fuels and emits greenhouse gases. To tackle this issue, photocatalytic nitrogen fixation using visible light is emerging as an effective alternative method. This strategy avoids carbon dioxide (CO2) emissions and harnesses the largest share of sunlight. In this work, we successfully incorporated a 5-nitro isophthalic acid linker into MOF-808 to introduce structural defects and open metal sites. This has allowed modulation of the electronic structure of the MOF and effectively reduced the band gap energy from 3.8 to 2.6 eV. Combination with g-C3N4 enhanced further NH3 production, as these two materials possess similar band gap energies, and g-C3N4 has shown excellent performance for this reaction. The nitro groups serve as acceptors, and their integration into the MOF structure allowed effective interaction with the free electron pairs on N-(C)3 in the g-C3N4 network nodes. Based on DFT calculations, it was concluded that the adsorption of N2 molecules on open metal sites caused a decrease in their triple bond energy. The modified MOF-808 showed superior performance compared with the other MOFs studied in terms of N2 photoreduction under visible light. This design concept offers valuable information about how to engineer band gap energy in MOF structures and their combination with appropriate semiconductors for solar-powered photocatalytic reactions, such as N2 or CO2 photoreduction.

Graphene-based field-effect transistors for biosensing: where is the field heading to?

Two-dimensional (2D) materials hold great promise for future applications, notably their use as biosensing channels in the field-effect transistor (FET) configuration. On the road to implementing one of the most widely used 2D materials, graphene, in FETs for biosensing, key issues such as operation conditions, sensitivity, selectivity, reportability, and economic viability have to be considered and addressed correctly. As the detection of bioreceptor-analyte binding events using a graphene-based FET (gFET) biosensor transducer is due to either graphene doping and/or electrostatic gating effects with resulting modulation of the electrical transistor characteristics, the gFET configuration as well as the surface ligands to be used have an important influence on the sensor performance. While the use of back-gating still grabs attention among the sensor community, top-gated and liquid-gated versions have started to dominate this area. The latest efforts on gFET designs for the sensing of nucleic acids, proteins and virus particles in different biofluids are presented herewith, highlighting the strategies presently engaged around gFET design and choosing the right bioreceptor for relevant biomarkers.

"Functional upcycling" of polymer waste towards the design of new materials.

Diversification of polymer waste recycling is one of the solutions to improve the current environmental scenario. Upcycling is a promising strategy for converting polymer waste into molecular intermediates and high-value products. Although the catalytic transformations into small molecules have been actively discussed, the methods and characteristics of upcycling into new materials have not yet been addressed. Recently, the functionalisation of polymer wastes (polyethylene terephthalate bottles, polypropylene surgical masks, rubber tires, etc.) and their conversion into new materials with enhanced functionality have been proposed as an appealing alternative for dealing with polymer waste recycling/treatment. In this review, the term 'functional upcycling' is introduced to designate any method of post-polymerisation modification or surface functionalisation without considerable polymer chain destruction to produce a new upcycled material with added value. This review explores the functional upcycling strategy with detailed consideration of the most common polymers, i.e., polystyrene, poly(methyl methacrylate), polyethylene, polypropylene, polyurethane, polyethylene terephthalate, polyvinyl chloride, polycarbonate, and rubber. We discuss the composition of plastic waste, reactivity, available physical/chemical agents for modification, and the interconnection between their properties and application. To date, upcycled materials have been successfully applied as adsorbents (including CO2), catalysts, electrode materials for energy storage and sensing, demonstrating a high added value. Importantly, the reviewed reports indicated that the specific performance of upcycled materials is generally comparable or higher than that of similar materials prepared from virgin polymer feedstock. All these advantages promote functional upcycling as a promising diversification approach against the common postprocessing methods employed for polymer waste. Finally, to identify the limitations and suggest future scope of research for each polymer, we comparatively analysed the aspects of functional upcycling with those of chemical and mechanical recycling, considering the energy and resource costs, toxicity of the used chemicals, environmental footprint, and the value added to the product.

Enhanced biosynthesis of coated silver nanoparticles using isolated bacteria from heavy metal soils and their photothermal-based antibacterial activity: integrating Response Surface Methodology (RSM) Hybrid Artificial Neural Network (ANN)-Genetic Algorithm (GA) strategies.

This study explores the biosynthesis of silver nanoparticles (AgNPs) using the Streptomyces tuirus S16 strain, presenting an eco-friendly alternative to mitigate the environmental and health risks of chemical synthesis methods. It focuses on optimizing medium culture conditions, understanding their physicochemical properties, and investigating their potential photothermal-based antibacterial application. The S16 strain was selected from soils contaminated with heavy metals to exploit its ability to produce diverse bioactive compounds. By employing the combination of Response Surface Methodology (RSM) and Artificial Neural Network (ANN)-Genetic Algorithm (GA) strategies, we optimized AgNPs synthesis, achieving an improvement of nearly 2.45 times the initial yield under specific conditions (Bennet's medium supplemented with glycerol [5 g/L] and casamino-acid [3 g/L] at 30 °C for 72 h). A detailed physicochemical characterization was conducted. Notably, the AgNPs were well dispersed, and a carbonaceous coating layer on their surface was confirmed using energy-dispersive X-ray spectroscopy. Furthermore, functional groups were identified using Fourier-transform infrared spectroscopy, which helped enhance the AgNPs' stability and biocompatibility. AgNPs also demonstrated efficient photothermal conversion under light irradiation (0.2 W/cm2), with temperatures increasing to 41.7 °C, after 30 min. In addition, treatment with light irradiation of E. coli K-12 model effectively reduced the concentration of AgNPs from 105 to 52.5 µg/mL, thereby enhancing the efficacy of silver nanoparticles in contact with the E. coli K-12.

Nanoparticles and Nanocolloidal Carbon: Will They Be the Next Antidiabetic Class That Targets Fibrillation and Aggregation of Human Islet Amyloid Polypeptide in Type 2 Diabetes?

Nanotechnology is revolutionizing human medicine. Nanoparticles (NPs) are currently used for treating various cancers, for developing vaccines, and for imaging, and other promises offered by NPs might come true soon. Due to the interplay between NPs and proteins, there is more and more evidence supporting the role of NPs for treating amyloid-based diseases. NPs can induce some conformational changes of the adsorbed protein molecules via various molecular interactions, leading to inhibition of aggregation and fibrillation of several and different amyloid proteins. Though an in depth understanding of such interactions between NPs and amyloid structures is still lacking, the inhibition of protein aggregation by NPs represents a new generation of innovative and effective medicines to combat metabolic diseases such as type 2 diabetes (T2D). Here, we lay out advances made in the field of T2D notably for optimizing protein aggregation inhibition strategies. This Account covers discussions about the current understanding of ß-cells, the insulin producing cells within the pancreas, under diabetic conditions, notably increased glucose and fatty acid levels, and the implication of these conditions on the formation of human islet amyloid polypeptide (hIAPP) amylin oligomers and aggregates. Owing to the great potential of carbon nanostructures to interfere with protein aggregation, an important part of this Account will be devoted to the state of the art of therapeutic options in the form of emerging nanomaterials-based amyloidosis inhibitors. Our group has recently made some substantial progress in this regard by investigating the impact of glucose and fatty acid concentrations on hIAPP aggregation and ß-cell toxicity. Furthermore, the great potential of carbon nanocolloids in reversing hIAPP aggregation under diabetic conditions will be highlighted as the approach has been validated on ß-cell cultures from rats. We hope that this Account will evoke new ideas and concepts in this regard. We give some lead references below on pancreatic ß-cell aspects and carbon quantum dots for managing diabetics and nanomedicine related aspects, a topic of interest in our laboratory.

In Vitro and Ex Vivo Models for Assessing Drug Permeation across the Cornea.

Drug permeation across the cornea remains a major challenge due to its unique and complex anatomy and physiology. Static barriers such as the different layers of the cornea, as well as dynamic aspects such as the constant renewal of the tear film and the presence of the mucin layer together with efflux pumps, all present unique challenges for effective ophthalmic drug delivery. To overcome some of the current ophthalmic drug limitations, the identification and testing of novel drug formulations such as liposomes, nanoemulsions, and nanoparticles began to be considered and widely explored. In the early stages of corneal drug development reliable in vitro and ex vivo alternatives, are required, to be in line with the principles of the 3Rs (Replacement, Reduction, and Refinement), with such methods being in addition faster and more ethical alternatives to in vivo studies. The ocular field remains limited to a handful of predictive models for ophthalmic drug permeation. In vitro cell culture models are increasingly used when it comes to transcorneal permeation studies. Ex vivo models using excised animal tissue such as porcine eyes are the model of choice to study corneal permeation and promising advancements have been reported over the years. Interspecies characteristics must be considered in detail when using such models. This review updates the current knowledge about in vitro and ex vivo corneal permeability models and evaluates their advantages and limitations.

Fabrication of a novel electrochemical biosensor based on a molecular imprinted polymer-aptamer hybrid receptor for lysozyme determination.

In this work, a novel, sensitive, and rapid electrochemical biosensor was employed to detect lysozyme (Lys) using a double receptor of molecular imprinted polymer (MIP)-aptamer. First, a glassy carbon electrode (GCE) was modified with a nanocomposite consisting of multi-wall carbon nanotubes (MWCNTs), nitrogen-doped carbon quantum dots (N-CQDs), and chitosan. Subsequently, aptamer (Apt)-Lys complex was immobilized on MWCNTs-N-CQDs-chitosan/GCE via binding between carboxyl groups present in the nanocomposite and the terminal amine groups of the aptamer. Following that, methylene blue monomer was electrochemically polymerized around the Apt-Lys complex on the MWCNTs-N-CQDs-chitosan/GCE surface. Finally, after the template removal, the remaining cavities along with the aptamers created a new hybrid receptor of MIP-aptamer. The MWCNTs-N-CQDs-chitosan nanocomposite could provide large amounts of carboxyl groups for binding to amino-functionalized aptamers, considerable electrical conductivity, and a high surface-to-volume ratio. These beneficial features facilitated the Apt-Lys complex immobilization and gave improved electrochemical signal. The obtained MIP-aptamer hybrid receptor allowed lysozyme determination even at concentrations as low as 4.26 fM within the functional range of 1 fM to 100 nM.

Exhaled breath condensate as bioanalyte: from collection considerations to biomarker sensing.

Since the SARS-CoV-2 pandemic, the potential of exhaled breath (EB) to provide valuable information and insight into the health status of a person has been revisited. Mass spectrometry (MS) has gained increasing attention as a powerful analytical tool for clinical diagnostics of exhaled breath aerosols (EBA) and exhaled breath condensates (EBC) due to its high sensitivity and specificity. Although MS will continue to play an important role in biomarker discovery in EB, its use in clinical setting is rather limited. EB analysis is moving toward online sampling with portable, room temperature operable, and inexpensive point-of-care devices capable of real-time measurements. This transition is happening due to the availability of highly performing biosensors and the use of wearable EB collection tools, mostly in the form of face masks. This feature article will outline the last developments in the field, notably the novel ways of EBA and EBC collection and the analytical aspects of the collected samples. The inherit non-invasive character of the sample collection approach might open new doors for efficient ways for a fast, non-invasive, and better diagnosis.

Deep Eutectic Solvents Comprising Organic Acids and Their Application in (Bio)Medicine.

Over the last years, we observed a significant increase in the number of published studies that focus on the synthesis and characterization of deep eutectic solvents (DESs). These materials are of particular interest mainly due to their physical and chemical stability, low vapor pressure, ease of synthesis, and the possibility of tailoring their properties through dilution or change of the ratio of parent substances (PS). DESs, considered as one of the greenest families of solvents, are used in many fields, such as organic synthesis, (bio)catalysis, electrochemistry, and (bio)medicine. DESs applications have already been reported in various review articles. However, these reports mainly described these components' basics and general properties without focusing on the particular, PS-wise, group of DESs. Many DESs investigated for potential (bio)medical applications comprise organic acids. However, due to the different aims of the reported studies, many of these substances have not yet been investigated thoroughly, which makes it challenging for the field to move forward. Herein, we propose distinguishing DESs comprising organic acids (OA-DESs) as a specific group derived from natural deep eutectic solvents (NADESs). This review aims to highlight and compare the applications of OA-DESs as antimicrobial agents and drug delivery enhancers-two essential fields in (bio)medical studies where DESs have already been implemented and proven their potential. From the survey of the literature data, it is evident that OA-DESs represent an excellent type of DESs for specific biomedical applications, owing to their negligible cytotoxicity, fulfilling the rules of green chemistry and being generally effective as drug delivery enhancers and antimicrobial agents. The main focus is on the most intriguing examples and (where possible) application-based comparison of particular groups of OA-DESs. This should highlight the importance of OA-DESs and give valuable clues on the direction the field can take.

Photocatalytic Performance of Perovskite and Metal-Organic Framework Hybrid Material for the Reduction of N2 to Ammonia.

The orthorhombic phase of KNbO3 perovskite has been applied for nitrogen (N2) photoreduction to ammonia (NH3). However, this material suffers from a low surface area and low ammonia production efficiency under UV light irradiation. To eliminate these barriers, we used a metal-organic framework (MOF), named as TMU-5 ([Zn(OBA)(BPDH)0.5]n·1.5DMF, where H2OBA = 4,4'-oxybis(benzoic acid) and BPDH = 2,5-bis(4-pyridyl)-3,4-diaza-2,4-hexadiene), for the synthesis of the KNbO3@TMU-5 hybrid material. KNbO3@TMU-5 achieved a NH3 production rate of 39.9 µmol·L-1·h-1·g-1 upon UV light irradiation, as compared to 20.5 µmol·L-1·h-1·g-1 recorded for KNbO3 under similar experimental conditions. Using different characterization techniques especially gas adsorption, cyclic voltammetry, X-ray photoelectron spectroscopy, photocurrent measurements, and Fourier transform infrared spectroscopy, it has been found that the higher photoactivity of KNbO3@TMU-5 in ammonia production is due to its higher surface area, higher electron-hole separation efficiency, and higher density of negative charges on Nb sites. This work shows that hybridization of conventional semiconductors (SCs) with photoactive MOFs can improve the photoactivity of the SC@MOF hybrid material in different reactions, especially kinetically complex reactions like photoconversion of nitrogen to ammonia.

The role of the surface ligand on the performance of electrochemical SARS-CoV-2 antigen biosensors.

Point-of-care (POC) technologies and testing programs hold great potential to significantly improve diagnosis and disease surveillance. POC tests have the intrinsic advantage of being able to be performed near the patient or treatment facility, owing to their portable character. With rapid results often in minutes, these diagnostic platforms have a high positive impact on disease management. POC tests are, in addition, advantageous in situations of a shortage of skilled personnel and restricted availability of laboratory-based analytics. While POC testing programs are widely considered in addressing health care challenges in low-income health systems, the ongoing pandemic of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections could largely benefit from fast, efficient, accurate, and cost-effective point-of-care testing (POCT) devices for limiting COVID-19 spreading. The unrestrained availability of SARS-CoV-2 POC tests is indeed one of the adequate means of better managing the COVID-19 outbreak. A large number of novel and innovative solutions to address this medical need have emerged over the last months. Here, we critically elaborate the role of the surface ligands in the design of biosensors to cope with the current viral outbreak situation. Their notable effect on electrical and electrochemical sensors' design will be discussed in some given examples. Graphical abstract.

Electrochemical and electronic detection of biomarkers in serum: a systematic comparison using aptamer-functionalized surfaces.

Sensitive and selective detection of biomarkers in serum in a short time has a significant impact on health. The enormous clinical importance of developing reliable methods and devices for testing serum levels of cardiac troponin I (cTnI), which are directly correlated to acute myocardial infarction (AMI), has spurred an unmatched race among researchers for the development of highly sensitive and cost-effective sensing formats to be able to differentiate patients with early onset of cardiac injury from healthy individuals with a mean cTnI level of 26 pg mL-1. Electronic- and electrochemical-based detection schemes allow for fast and quantitative detection not otherwise possible at the point of care. Such approaches rely largely on voltammetric and field-effect-based readouts. Here, we systematically investigate electric and electrochemical point-of-care sensors for the detection of cTnI in serum samples by using the same surface receptors, cTnI aptamer-functionalized CVD graphene-coated interdigated gold electrodes. The analytical performances of both sensors are comparable with a limit of detection (LoD) of 5.7 ± 0.6 pg mL-1(electrochemical) and 3.3 ± 1.2 pg mL-1 (electric). However, both sensors exhibit different equilibrium dissociation constant (KD) values between the aptamer-linked surface receptor and the cTnI analyte, being 160 pg mL-1 for the electrochemical and about three times lower for the electrical approach with KD = 51.4 pg mL-1. This difference is believed to be related to the use of a redox mediator in the electrochemical sensor for readout. The ability of the redox mediator to diffuse from the solution to the surface via the cTnI/aptamer interface is hindered, correlating to higher KD values. In contrast, the electric readout has the advantage of being label-free with a sensing limitation due to ionic strength effects, which can be limited using poly(ethylene) glycol surface ligands.

Effective PDT/PTT dual-modal phototherapeutic killing of bacteria by using poly(N-phenylglycine) nanoparticles.

This study investigated, for the first time, the antimicrobial properties of polyethylene glycol-functionalized poly(N-phenylglycine) nanoparticles (PNPG-PEG NPs). PNPG-PEG NPs exhibit high extinction coefficient in the near-infrared (NIR) region; they can convert light energy into heat energy with high thermal transformation efficiency. Additionally, they can generate cytotoxic reactive oxygen species (ROS) upon light irradiation. Also, PNPG-PEG NPs are not cytotoxic. All these properties make them appropriate for combined dual-modal photothermal and photodynamic therapies. The antibacterial activity of PNPG-PEG NPs was assessed using Escherichia coli (Gram-negative) and Staphylococcus aureus (Gram-positive) pathogenic strains. The results revealed that NIR light (810 nm) irradiation for 10 min could kill effectively the planktonic bacteria and destroy Escherichia coli and Staphylococcus aureus biofilms. The results demonstrated that PNPG-PEG NPs represent a very effective nanoplatform for killing of pathogenic bacteria.

The impact of chemical engineering and technological advances on managing diabetes: present and future concepts.

Monitoring blood glucose levels for diabetic patients is critical to achieve tight glycaemic control. As none of the current antidiabetic treatments restore lost functional ß-cell mass in diabetic patients, insulin injections and the use of insulin pumps are most widely used in the management of glycaemia. The use of advanced and intelligent chemical engineering, together with the incorporation of micro- and nanotechnological-based processes have lately revolutionized diabetic management. The start of this concept goes back to 1974 with the description of an electrode that repeatedly measures the level of blood glucose and triggers insulin release from an infusion pump to enter the blood stream from a small reservoir upon need. Next to the insulin pumps, other drug delivery routes, including nasal, transdermal and buccal, are currently investigated. These processes necessitate competences from chemists, engineers-alike and innovative views of pharmacologists and diabetologists. Engineered micro and nanostructures hold a unique potential when it comes to drug delivery applications required for the treatment of diabetic patients. As the technical aspects of chemistry, biology and informatics on medicine are expanding fast, time has come to step back and to evaluate the impact of technology-driven chemistry on diabetics and how the bridges from research laboratories to market products are established. In this review, the large variety of therapeutic approaches proposed in the last five years for diabetic patients are discussed in an applied context. A survey of the state of the art of closed-loop insulin delivery strategies in response to blood glucose level fluctuation is provided together with insights into the emerging key technologies for diagnosis and drug development. Chemical engineering strategies centered on preserving and regenerating functional pancreatic ß-cell mass are evoked in addition as they represent a permanent solution for diabetic patients.

TRPM8 as an Anti-Tumoral Target in Prostate Cancer Growth and Metastasis Dissemination.

In the fight against prostate cancer (PCa), TRPM8 is one of the most promising clinical targets. Indeed, several studies have highlighted that TRPM8 involvement is key in PCa progression because of its impact on cell proliferation, viability, and migration. However, data from the literature are somewhat contradictory regarding the precise role of TRPM8 in prostatic carcinogenesis and are mostly based on in vitro studies. The purpose of this study was to clarify the role played by TRPM8 in PCa progression. We used a prostate orthotopic xenograft mouse model to show that TRPM8 overexpression dramatically limited tumor growth and metastasis dissemination in vivo. Mechanistically, our in vitro data revealed that TRPM8 inhibited tumor growth by affecting the cell proliferation and clonogenic properties of PCa cells. Moreover, TRPM8 impacted metastatic dissemination mainly by impairing cytoskeleton dynamics and focal adhesion formation through the inhibition of the Cdc42, Rac1, ERK, and FAK pathways. Lastly, we proved the in vivo efficiency of a new tool based on lipid nanocapsules containing WS12 in limiting the TRPM8-positive cells' dissemination at metastatic sites. Our work strongly supports the protective role of TRPM8 on PCa progression, providing new insights into the potential application of TRPM8 as a therapeutic target in PCa treatment.

Synthesis of Cyano-Benzylidene Xanthene Synthons Using a Diprotic Brønsted Acid Catalyst, and Their Application as Efficient Inhibitors of Aluminum Corrosion in Alkaline Solutions.

Novel cyano-benzylidene xanthene derivatives were synthesized using one-pot and condensation reactions. A diprotic Brønsted acid (i.e., oxalic acid) was used as an effective catalyst for the promotion of the synthesis process of the new starting xanthene-aldehyde compound. Different xanthene concentrations (ca. 0.1-2.0 mM) were applied as corrosion inhibitors to control the alkaline uniform corrosion of aluminum. Measurements were conducted in 1.0 M NaOH solution using Tafel extrapolation and linear polarization resistance (LPR) methods. The investigated xanthenes acted as mixed-type inhibitors that primarily affect the anodic process. Their inhibition efficiency values were enhanced with inhibitor concentration, and varied according to their chemical structures. At a concentration of 2.0 mM, the best-performing studied xanthene derivative recorded maximum inhibition efficiency values of 98.9% (calculated via the Tafel extrapolation method) and 98.4% (estimated via the LPR method). Scanning electron microscopy (SEM) was used to examine the morphology of the corroded and inhibited aluminum surfaces, revealing strong inhibitory action of each studied compound. High-resolution X-ray photoelectron spectroscopy (XPS) profiles validated the inhibitor compounds' adsorption on the Al surface. Density functional theory (DFT) and Monte Carlo simulations were applied to investigate the distinction of the anticorrosive behavior among the studied xanthenes toward the Al (111) surface. The non-planarity of xanthenes and the presence of the nitrile group were the key players in the adsorption process. A match between the experimental and theoretical findings was evidenced.

Au-assisted polymerization of conductive poly(N-phenylglycine) as high-performance positive electrodes for asymmetric supercapacitors.

Herein, a novel conductive poly(N-phenylglycine) (PNPG) polymer was successfully prepared, byin situelectrochemical polymerization method (+0.75 VversusAg/AgCl) for 10 min, on flexible stainless-steel plate coated with a thin Au film (Au/SS) to serve as a binder-free pseudocapacitive PNPG/Au/SS electrode for energy storage devices. Compared to the electrode without Au coating, PNPG/Au/SS electrode exhibited better electrochemical performance with larger specific capacitance (495 F g-1at a current density of 2 A g-1), higher rate performance and lower resistance, which are good indications to act as a positive electrode for asymmetric supercapacitor devices. Combined with activated carbon as a negative electrode, an asymmetric supercapacitor device was constructed. It displayed a specific capacitance of 38 F g-1at a current density of 0.5 A g-1and an energy density of 5.3 Wh kg-1at a power density of 250 W kg-1. Experimentally, two asymmetric supercapacitor devices were connected in series to power a home-made windmill continuously for 8 s, revealing the high potential of this novel conductive polymer material for energy storage application.

Non-enzymatic electrochemical cholesterol sensor based on strong host-guest interactions with a polymer of intrinsic microporosity (PIM) with DFT study.

Advances in materials science have accelerated the development of diagnostic tools with the last decade witnessing the development of enzyme-free sensors, owing to the improved stability, low cost and simple fabrication of component materials. However, the specificity of non-enzymatic sensors for certain analytes still represents a challenging task, for example the determination of cholesterol level in blood is vital due to its medical relevance. In this work, a reagent displacement assay for cholesterol sensing in serum samples was developed. It is based on coating of a glassy carbon electrode with a polymer of intrinsic microporosity (PIM) that forms a host-guest complex with methylene blue (MB). In the presence of cholesterol, the MB electroactive probe was displaced due to the stronger association of cholesterol guest to the PIM host. The decrease in the oxidative current was proportional to the cholesterol concentration achieving a detection limit of approximately 0.1 nM. Moreover, to further assist the experimental studies, comprehensive theoretical calculations are also performed by using density functional theory (DFT) calculations.