Electrochemical Sensing and Biosensing Platform Based on Biomass-Derived Macroporous Carbon Materials

Sensitive dual-mode detection of carbendazim by molecularly imprinted electrochemical sensor based on biomass-derived carbon-loaded gold nanoparticles

A dual-mode electrochemical sensor was fabricated for carbendazim (CBD) detection. Biomass-derived carbon loaded gold nanoparticles (AuNPs/BC) were firstly coated on a glassy carbon electrode (GCE), and then molecularly imprinted polymer (MIP) of o-aminophenol was prepared on the resulting AuNPs/BC/GCE through electrochemical method in the presence of CBD. The AuNPs/BC had excellent conductivity, large surface and good electrocatalysis, while the imprinted film presented good recognition. Thus, the obtained MIP/AuNPs/BC/GCE exhibited sensitive current response to CBD. Furthermore, the sensor displayed good impedance response to CBD. Hence, a dual-mode detection platform for CBD was established. Under optimum conditions, the linear response ranges were as wide as 1.0 nM - 15 μM (by differential pulse voltammetry, DPV) and 1.0 nM - 10 μM (by electrochemical impedance spectroscopy, EIS), and the detection limits for these two methods were as low as 0.30 nM (S/N = 3) and 0.24 nM (S/N = 3), respectively. The sensor also had high selectivity, stability and reproducibility. The sensor was applied to detect CBD in spiked real samples, including cabbage, peach, apple and lake water, and the recoveries were 85.8-108% (by DPV) and 91.4-110% (by EIS); the relative standard deviations (RSD) were 3.4-5.3% (by DPV) and 3.7-5.1% (by EIS), respectively. The results were consistent with that obtained by high-performance liquid chromatography. Therefore, this sensor is a simple and effective tool for CBD detection, and it has good application potential.

Nanostructured N, S, and P-Doped Elaeagnus Angustifolia Gum-Derived Porous Carbon with Electrodeposited Silver for Enhanced Electrochemical Sensing of Acetaminophen

Acetaminophen (N-acetyl-p-aminophenol, APAP) is regularly used for antipyretic and analgesic purposes. Overdose or long-term exposure to APAP could lead to liver damage and hepatotoxicity. In this study, the approach of enhanced electrochemical detection of APAP by nanostructured biomass carbon/silver was developed. Porous biomass carbon derived from Elaeagnus Angustifolia gum was prepared by pyrolysis with co-doping of electron-rich elements of nitrogen, sulfur, and phosphorus. The electrodeposition of silver onto a glassy carbon electrode modified with porous carbon could enhance the sensing signal towards APAP. Two linear ranges from 61 nM to 500 μM were achieved with a limit of detection of 33 nM. The developed GCE sensor has good anti-interference, stability, reproducibility, and human urine sample analysis performance. The silver-enhanced biomass carbon GCE sensor extends the application of biomass carbon, and its facile preparation approach could be used in constructing disposable sensing chips in the future.

Electrochemical Biosensors in the Diagnosis of Acute and Chronic Leukemias

Until now, morphological assessment with an optical or electronic microscope, fluorescence in situ hybridization, DNA sequencing, flow cytometry, polymerase chain reactions, and immunohistochemistry have been employed for leukemia identification. Nevertheless, despite their numerous different vantages, it is difficult to recognize leukemic cells correctly. Recently, the electrochemical evaluation with a nano-sensing interface seems an attractive alternative. Electrochemical biosensors measure the modification in the electrical characteristics of the nano-sensing interface, which is modified by the contact between a biological recognition element and the analyte objective. The implementation of nanosensors is founded not on single nanomaterials but rather on compilating these components efficiently. Biosensors able to identify the molecules of deoxyribonucleic acid are defined as DNA biosensors. Our review aimed to evaluate the literature on the possible use of electrochemical biosensors for identifying hematological neoplasms such as acute promyelocytic leukemia, acute lymphoblastic leukemia, and chronic myeloid leukemia. In particular, we focus our attention on using DNA electrochemical biosensors to evaluate leukemias.

A recent advancement on the applications of nanomaterials in electrochemical sensors and biosensors

Industrialization and globalization, both on an international and local scale, have caused large quantities of toxic chemicals to be released into the environment. Thus, developing an environmental pollutant sensor platform that is sensitive, reliable, and cost-effective is extremely important. In current years, considerable progress has been made in the expansion of electrochemical sensors and biosensors to monitor the environment using nanomaterials. A large number of emerging biomarkers are currently in existence in the biological fluids, clinical, pharmaceutical and bionanomaterial-based electrochemical biosensor platforms have drawn much attention. Electrochemical systems have been used to detect biomarkers rapidly, sensitively, and selectively using biomaterials such as biopolymers, nucleic acids, proteins etc. In this current review, several recent trends have been identified in the growth of electrochemical sensor platforms using nanotechnology such as carbon nanomaterials, metal oxide nanomaterials, metal nanoparticles, biomaterials and polymers. The integration strategies, applications, specific properties and future projections of nanostructured materials for emerging progressive sensor platforms are also observed. The objective of this review is to provide a comprehensive overview of nanoparticles in the field of electrochemical sensors and biosensors.

Highly sensitive detection of carbendazim in juices based on mung bean-derived porous carbon@chitosan composite modified electrochemical sensor

We reported a simple and scalable strategy for the preparation of mung bean-derived porous carbon@chitosan (MBC@CTS) composite, which was used to optimize the glassy carbon electrode (GCE). The MBC@CTS/GCE sensor was applied for the carbendazim (CBZ) detection. For the MBC@CTS composite, MBC with three-dimensional hierarchical structure presented large specific surface area, good adsorbability, and high electrical conductivity, while CTS had good film-forming property, hydrophilicity performance, and adhesion capacity. The MBC@CTS/GCE sensor exhibited wonderful electrochemical detection performance towards CBZ. Under the optimized conditions, the MBC@CTS/GCE sensor showed a linear concentration range from 0.1 to 20 μM with relatively low limit of detection (LOD) of 20 nM. In addition, the fabricated sensor with good reproducibility, stability, and selectivity were successfully applied for the CBZ detection in apple and tomato juices with low relative standard deviation of 2.4 %-4.2% and satisfactory recoveries of 98.8-103.2%.

Echem methods and electrode types of the current in vivo electrochemical sensing

For a long time, people have been eager to realize continuous real-time online monitoring of biological compounds. Fortunately, in vivo electrochemical biosensor technology has greatly promoted the development of biological compound detection. This article summarizes the existing in vivo electrochemical detection technologies into two categories: microdialysis (MD) and microelectrode (ME). Then we summarized and discussed the electrode surface time, pollution resistance, linearity and the number of instances of simultaneous detection and analysis, the composition and characteristics of the sensor, and finally, we also predicted and prospected the development of electrochemical technology and sensors in vivo.

Construction of a binder-free non-enzymatic glucose sensor based on Cu@Ni core-shell nanoparticles anchored on 3D chiral carbon nanocoils-nickel foam hierarchical scaffold

Bimetallic nanostructures composited with carbonaceous materials are the potential contenders for quantitative glucose measurement owing to their unique nanostructures, high biomimetic activity, synergistic effects, good conductivity and chemical stability. In the present work, chemical vapors deposition technique has been employed to grow 3D carbon nanocoils (CNCs) with a chiral morphology on hierarchical macroporous nickel foam (NF) to get a CNCs/NF scaffold. Following, bimetallic Cu@Ni core-shell nanoparticles (CSNPs) are effectively coupled with this scaffold through a facile solvothermal route in order to fabricate a binder-free novel Cu@Ni CSNPs/CNCs/NF hybrid nanostructure. The constructed free-standing 3D hierarchical composite electrode guarantees highly efficient glucose redox activity due to core-shell synergistic effects, enhanced electrochemical active surface area, excellent electrochemical stability, improved conductivity with better ion diffusivity and accelerated reaction kinetics. Being a non-enzymatic glucose sensor, this electrode achieves highly swift response time of 0.1 s, ultra-high sensitivity of 6905 μA mM^-1 cm^-2, low limit of detection of 0.03 μM along with potential selectivity and good storage stability. Moreover, the proposed sensor is also tested successfully for the determination of glucose concentration in human serum samples under good recovery ranging from 96.6 to 102.1 %. The 3D Cu@Ni CSNPs/CNCs/NF composite electrode with unprecedented catalytic performance can be utilized as an ideal biomimetic catalyst in the field of non-enzymatic glucose sensing.

A Strategy for Accessing Nanobody-Based Electrochemical Sensors for Analyte Detection in Complex Media

Nanobodies are single variable domain antibodies isolated from camelids and are rapidly distinguishing themselves as ideal recognition elements in biosensors due to their comparative stability, ease of production and isolation, and high binding affinities. However, transducing analyte binding by nanobodies in real time is challenging, as most nanobodies do not directly produce an optical or electrical signal upon target recognition. Here, we report a general strategy to fabricate sensitive and selective electrochemical sensors incorporating nanobodies for detecting target analytes in heterogeneous media, such as cell lysate. Graphite felt can be covalently functionalized with recombinant HaloTag-modified nanobodies. Subsequent encapsulation with a thin layer of a hydrogel using a vapor deposition process affords encapsulated electrodes that directly display a decrease in current upon antigen binding, without added redox mediators. Differential pulse voltammetry affords clear and consistent decreases in electrode current across multiple electrode samples for specific antigen concentrations. The change in observed current vs increasing antigen concentration follows Langmuir binding characteristics, as expected. Importantly, selective and repeatable target binding in unpurified cell lysate is only demonstrated by the encapsulated electrode, with an antigen detection limit of ca. 30 pmol, whereas bare electrodes lacking encapsulation produce numerous false positive signals in control experiments.

Fourth-generation glucose sensors composed of copper nanostructures for diabetes management: A critical review

More than five decades have been invested in understanding glucose biosensors. Yet, this immensely versatile field has continued to gain attention from the scientific world to better understand and diagnose diabetes. However, such extensive work done to improve glucose sensing devices has still not yielded desirable results. Drawbacks like the necessity of the invasive finger-pricking step and the lack of optimization of diagnostic interventions still need to be considered to improve the testing process of diabetic patients. To upgrade the glucose-sensing devices and reduce the number of intermediary steps during glucose measurement, fourth-generation glucose sensors (FGGS) have been introduced. These sensors, made using robust electrocatalytic copper nanostructures, improve diagnostic efficiency and cost-effectiveness. This review aims to present the essential scientific progress in copper nanostructure-based FGGS in the past 10 years (2010 to present). After a short introduction, we presented the working principles of these sensors. We then highlighted the importance of copper nanostructures as advanced electrode materials to develop reliable real-time FGGS. Finally, we cover the advantages, shortcomings, and prospects for developing highly sensitive, stable, and specific FGGS.

Synthesis of a clustered carbon aerogel interconnected by carbon balls from the biomass of taros for construction of a multi-functional electrochemical sensor

In this study, a clustered carbon aerogel interconnected by carbon balls (CCAI-CB) was prepared as an electrode material to construct a multi-functional electrochemical sensor. CCAI-CB derived from taros (Colocasia esculenta (L). Schott) possesses meso-macroporous structure and plenty of defective sites, and shows notable activity in electrocatalysis as an electrode material. We investigated the application of CCAI-CB modified glassy carbon electrode (CCAI-CB/GCE) for determination of ascorbic acid (AA) and hydrogen peroxide (H₂O₂). Compared with carbon nanotubes (CNTs) modified GCE (CNTs/GCE) and bare GCE, CCAI-CB/GCE shows lower detection limit (0.23 μM for AA and 1.31 μM, S/N = 3), higher sensitivities (220.53, 148.86 or 94.39 μA mM^-1 cm^-2 for AA and 83.06 or 49.07 μA mM^-1 cm^-2 for H₂O₂). Concentrations of AA and H₂O₂ in real samples were determined at CCAI-CB/GCE with satisfactory detection results obtained. In addition, when the CCAI-CB/GCE was used for electrocatalysis of other biomolecules, it also exhibits high electrochemical activity. Thus, CCAI-CB could be a promising electrode material for the construction of multi-functional electrochemical sensors.

The facile synthesis of a Co3O4-NiNP composite as an electrochemical non-enzymatic sensing platform for small chemical molecules

In this paper, a new Co3O4-Ni nanocomposite-modified glassy carbon electrode (Co3O4-NiNPs/GCE) was successfully constructed and used to detect glucose and hydrogen peroxide (H2O2). The morphologies and structures of the Co3O4 and Co3O4-Ni nanocomposites were characterized via transmission electron microscopy (TEM), scanning electron microscopy (SEM), and X-ray diffraction (XRD). The construction process of the modified electrode was characterized via electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) techniques. Co3O4-NiNPs/GCE shows more excellent electrocatalytic activity for the detection of glucose and H2O2 compared with Co3O4/GCE and NiNPs/GCE. The amperometric i-t method was used for the quantitative analysis of glucose and H2O2. The plots of current difference versus concentration of glucose and H2O2 were linear in the range of 0.3-550 μM and 0.5-89 μM, respectively. The corresponding limits of detection (LODs) were 0.086 μM and 0.23 μM for glucose and H2O2, respectively. This recommended sensor was successfully applied for the quantitative analysis of glucose in fruit and H2O2 in water samples.

Functionalized carbonized monarch butterfly wing scales (FCBW) ornamented by β-Co(OH)2 nanoparticles: an investigation on its microwave, magnetic, and optical characteristics

In this research, a bioinspired carbon structure was applied as a novel, unique, green, affordable, light weight, thin, and broadband microwave absorbing material. Briefly, the monarch butterfly wing scales were pyrolyzed and then CBWs were functionalized using oxidative treatments, following that they were ornamented by hexagonal β-Co(OH)₂ nanoparticles to improve their microwave absorbing features based on an innovative complementary method by combining sonochemistry and hydrothermal routes. Noticeably, the polyacrylonitrile (PAN) was used as a practical medium to fabricate the microwave absorbers developing an integrated structure and augmenting the relaxation loss mechanism. Various analyses were applied to identify the prepared samples including x-ray powder diffraction, diffuse reflection spectroscopy, Fourier transform infrared, field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), vibrating sample magnetometer, and vector network analyzer. The net-like morphology of FCBWs were fully coated by the hierarchical hexagonal β-Co(OH)₂ nanoparticles. FCBW illustrated a saturation magnetization of 0.06 emu g^-1 originated from its defects, distortions, dislocations, unique morphology, as well as folding, developing localized magnetic moments. Noticeably, inserting FCBWs narrow the energy bandgap of β-Co(OH)₂ nanoparticles, amplifying their light absorption and polarizability, desirable for the microwave attenuation. As revealed, FCBW/β-Co(OH)₂/PAN nanocomposite gained strong reflection loss (RL) of 68.41 at 9.08 GHz, while FCBW/PAN achieved broadband efficient bandwidth as wide as 7.97 GHz (RL > 10 dB) with a thickness of 2.00 mm. More significantly, β-Co(OH)₂/PAN nanocomposites demonstrated salient efficient bandwidth of 3.62 GHz (RL > 20 dB) with only 2.50 mm in thickness. Noteworthy, the eye-catching microwave absorptions were obtained by only filler loading of 10 Wt%. The remarkable microwave absorbing properties of the samples were generated from their microwave absorbing mechanisms which were scrupulously dissected. More significantly, the negative imaginary parts were obtained, originated from the produced secondary fields.

Physico-chemical properties and toxicological effects on plant and algal models of carbon nanosheets from a nettle fibre clone

Carbon nanosheets are two-dimensional nanostructured materials that have applications as energy storage devices, electrochemical sensors, sample supports, filtration membranes, thanks to their high porosity and surface area. Here, for the first time, carbon nanosheets have been prepared from the stems and leaves of a nettle fibre clone, by using a cheap and straight-forward procedure that can be easily scaled up. The nanomaterial shows interesting physical parameters, namely interconnectivity of pores, graphitization, surface area and pore width. These characteristics are similar to those described for the nanomaterials obtained from other fibre crops. However, the advantage of nettle over other plants is its fast growth and easy propagation of homogeneous material using stem cuttings. This last aspect guarantees homogeneity of the starting raw material, a feature that is sought-after to get a nanomaterial with homogeneous and reproducible properties. To evaluate the potential toxic effects if released in the environment, an assessment of the impact on plant reproduction performance and microalgal growth has been carried out by using tobacco pollen cells and the green microalga Pseudokirchneriella subcapitata. No inhibitory effects on pollen germination are recorded, while algal growth inhibition is observed at higher concentrations of leaf carbon nanosheets with lower graphitization degree.

Sweet potato derived three-dimensional carbon aerogels with a hierarchical meso-macroporous and branching nanostructure for electroanalysis

In this paper, sweet potatoes (Ipomoea batatas) are used as low-cost precursors to synthesize carbon aerogels with a hierarchical meso-macroporous and branching nanostructure (HMM-BNCA). An HMM-BNCA-modified glassy carbon electrode (GCE) (HMM-BNCA/GCE) exhibits high electrocatalytic activity for some electroactive biomolecules. For ascorbic acid (AA), the HMM-BNCA/GCE exhibits low oxidation peak potential and detection limit (-0.005 V and 0.45 μM, S/N = 3), high sensitivities (195.43 and 121.00 μA mM-1 cm-2) and wide linear ranges (10-1250 μM and 1250-4750 μM), which are superior to those obtained at the GCE and carbon nanotube (CNT)-modified GCE (CNT/GCE). The HMM-BNCA/GCE exhibits significant resistance to fouling and the interfering substances for the detection of AA. The successful and accurate detection of AA in real samples (such as vitamin C injections and vitamin C soft drinks) in this work demonstrates the feasibility and tremendous potential of HMM-BNCA/GCE for the analysis of AA in complex systems.

Recent advances in nanomaterial-modified electrical platforms for the detection of dopamine in living cells

Dopamine is a key neurotransmitter that plays essential roles in the central nervous system, including motor control, motivation, arousal, and reward. Thus, abnormal levels of dopamine directly cause several neurological diseases, including depressive disorders, addiction, and Parkinson's disease (PD). To develop a new technology to treat such diseases and disorders, especially PD, which is currently incurable, dopamine release from living cells intended for transplantation or drug screening must be precisely monitored and assessed. Owing to the advantages of miniaturisation and rapid detection, numerous electrical techniques have been reported, mostly in combination with various nanomaterials possessing specific nanoscale geometries. This review highlights recent advances in electrical biosensors for dopamine detection, with a particular focus on the use of various nanomaterials (e.g., carbon-based materials, hybrid gold nanostructures, metal oxides, and conductive polymers) on electrode surfaces to improve both sensor performance and biocompatibility. We conclude that this review will accelerate the development of electrical biosensors intended for the precise detection of metabolite release from living cells, which will ultimately lead to advances in therapeutic materials and techniques to cure various neurodegenerative disorders.

Dual antifungal activity against Candida albicans of copper metallic nanostructures and hierarchical copper oxide marigold-like nanostructures grown in situ in the culture medium

AIMS

This study aimed to determine in vitro activity of copper nanoparticles and copper nanowires against Candida albicans strains and to assess their effects on morphology and submicron structure.

METHODS AND RESULTS

The microdilution method determined the minimal inhibitory concentration (MIC) of copper nanoparticles (CuNPs) and copper nanowires (CuNWs) against three strains of C. albicans: ATCC 10231 and two clinical strains (C and E). Effects on the morphology and ultrastructure of C. albicans strains were examined by scanning electron microscopy and transmission electron microscopy. MIC for CuNPs was 129·7 µg ml^-1 for strain ATCC 10231, 1037·5 µg ml^-1 for strain C and 518·8 µg ml^-1 for strain E. MIC for CuNWs was similar for all strains tested (260·3 µg ml^-1 ). SEM and TEM studies showed alterations in morphology, cell wall and the complete collapse of the yeast after incubation with CuNPs. In contrast, most of the yeast cells maintained their structure with an intact cell wall, and only decreased the number and size of fimbriae when C. albicans was exposed to CuNWs. CuNPs and CuNWs formed hierarchical copper oxide nanostructures growing in situ in the culture medium. Results suggest a dual mechanism for antifungal activity: (i) free Cu²⁺ ions act as a biocide, (ii) sharp edges of marigold-like petal nanostructures could injure the cellular wall and membrane and cause the death of the yeast.

CONCLUSIONS

CuNPs and CuNWs inhibited the growth of the three strains of C. albicans tested. Moreover, CuNPs disrupted cell wall with leakage of the cytoplasmic content. Each concentration of the series used for the determination of the activity of CuNPs and nanowires against C. albicans formed copper oxide marigold-like nanostructures.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study suggests that CuNPs and CuNWs are good candidates for formulating new therapeutic agents for candidiasis.

Biomass-Derived Multilayer-Structured Microparticles for Accelerated Hemostasis and Bone Repair

It is very desirable to develop advanced sustainable biomedical materials with superior biosafety and bioactivity for clinical applications. Herein, biomass-derived multilayer-structured absorbable microparticles (MQ x T y ) composed of starches and plant polyphenols are readily constructed for the safe and effective treatment of bone defects with intractable bleeding by coating multiple layers of quaternized starch (Q+) and tannic acid onto microporous starch microparticles via facile layer-by-layer assembly. MQ x T y microparticles exhibit efficient degradability, low cytotoxicity, and good blood compatibility. Among various MQ x T y microparticles with distinct Q+/T- double layers, MQ2T2 with outmost polyphenol layer possess the unique properties of platelet adhesion/activation and red blood cell aggregation, resulting in the best hemostatic performance. In a mouse cancellous-bone-defect model, MQ2T2 exhibits the favorable hemostatic effect, low inflammation/immune responses, high biodegradability, and promoted bone repair. A proof-of-concept study of beagles further confirms the good performance of MQ2T2 in controlling intractable bleeding of bone defects. The present work demonstrates that such biomass-based multilayer-structured microparticles are very promising biomedical materials for clinical use.

Sensors Made of Natural Renewable Materials: Efficiency, Recyclability or Biodegradability-The Green Electronics

Nowadays, sensor devices are developing fast. It is therefore critical, at a time when the availability and recyclability of materials are, along with acceptability from the consumers, among the most important criteria used by industrials before pushing a device to market, to review the most recent advances related to functional electronic materials, substrates or packaging materials with natural origins and/or presenting good recyclability. This review proposes, in the first section, passive materials used as substrates, supporting matrixes or packaging, whether organic or inorganic, then active materials such as conductors or semiconductors. The last section is dedicated to the review of pertinent sensors and devices integrated in sensors, along with their fabrication methods.

The role of carbon dots - derived underlayer in hematite photoanodes

Hematite is a promising candidate as photoanode for solar-driven water splitting, with a theoretically predicted maximum solar-to-hydrogen conversion efficiency of ∼16%. However, the interfacial charge transfer and recombination greatly limits its activity for photoelectrochemical water splitting. Carbon dots exhibit great potential in photoelectrochemical water splitting for solar to hydrogen conversion as photosensitisers and co-catalysts. Here we developed a novel carbon underlayer from low-cost and environmental-friendly carbon dots through a facile hydrothermal process, introduced between the fluorine-doped tin oxide conducting substrate and hematite photoanodes. This led to a remarkable enhancement in the photocurrent density. Owing to the triple functional role of carbon dots underlayer in improving the interfacial properties of FTO/hematite and providing carbon source for the overlayer as well as the change in the iron oxidation state, the bulk and interfacial charge transfer dynamics of hematite are significantly enhanced, and consequently led to a remarkable enhancement in the photocurrent density. The results revealed a substantial improvement in the charge transfer rate, yielding a charge transfer efficiency of up to 80% at 1.25 V vs. RHE. In addition, a significant enhancement in the lifetime of photogenerated electrons and an increased carrier density were observed for the hematite photoanodes modified with a carbon underlayer, confirming that the use of sustainable carbon nanomaterials is an effective strategy to boost the photoelectrochemical performance of semiconductors for energy conversion.

Hydrophobic Magnetic Porous Material of Eichhornia crassipes for Highly Efficient Oil Adsorption and Separation

Many oil adsorption materials are composed of nonrenewable raw materials, and their disposal can increase resource consumption and cause new environmental pollution. In this paper, the carbonized Eichhornia crassipes (CEC) were immobilized with Fe₃O₄ magnetic nanoparticles and modified with 1H, 1H, 2H, 2H-perfluorooctyltriethoxysilane (PFOS) to prepare an oil adsorption material, referred to here as CEC/Fe₃O₄/PFOS. The magnetic and mechanical strength of the CEC was enhanced by adding Fe₃O₄ magnetic particles, which enable it efficient to dispose the oil/water solution. CEC/Fe₃O₄/PFOS shows high porosity (83.53%), low skeletal density (0.487 g/cm³), excellent magnetism, ultrahigh oil absorption capacity (49.94-140.90 g/g), hydrophobic performances with a water contact angle of 150.1 ± 2.3°, and a sliding angle of 10.5°. It is worth noting that the material can be recycled, and the absorbed oil is obtained by distillation. Therefore, this work may provide a candidate for solving the problem of oil pollution using E. crassipes.

Synthesis of an ordered nanoporous Cu/Ni/Au film for sensitive non-enzymatic glucose sensing

Ordered nanoporous Cu/Ni/Au film was prepared by electrochemical deposition and magnetron sputtering using an anodic aluminium oxide template. The fabricated porous film has a uniform hexagonal pore size structure, a long-range ordered arrangement, and a pore diameter of approximately 40 nm. Following the dissolution of the template, the independent Cu/Ni/Au film is devolved to an ITO substrate as an effective non-enzyme glucose detection sensor. The sensor has good electrocatalytic performance with two specific linear ranges of 0.5 μM to 3.0 mM and 3.0–7.0 mM and high sensitivities of 4135 and 2972 μA mM⁻¹ cm⁻², respectively. The lower detection limit was 0.1 μM with a signal-to-noise ratio of 3. Additionally, the sensor features excellent selectivity and stability. These satisfactory results indicate that Cu/Ni/Au film is a promising platform for the development of non-enzymatic glucose sensors.

Ordered nanoporous Cu/Ni/Au film prepared by template method could be transferred and used as an effective glucose sensor.

Influence of the Silver Nanoparticles (AgNPs) Formation Conditions onto Titanium Dioxide (TiO2) Nanotubes Based Electrodes on Their Impedimetric Response

This paper presents the comparison of the effects of three methods of production of silver spherical and near-spherical nanoparticles (AgNPs) on the titanium dioxide nanotubes (TNT) base: cyclic voltammetry, chronoamperometry, and sputter deposition. It also evaluates the influence of silver nanoparticles on the electrochemical properties of the developed electrodes. The novelty of this research was to fabricate regular AgNPs free of agglomerates uniformly distributed onto the TNT layer, which has not been accomplished with previous attempts. The applied methods do not require stabilizing and reducing reagents. The extensive electrochemical characteristic of AgNP/TNT was performed by open circuit potential and electrochemical impedance spectroscopy methods. For AgNPs/TNT obtained by each method, the impedance module of these electrodes was up to 50% lower when compared to TNT, which means that AgNPs enabled more efficient electron transfer due to the effective area increase. In addition, the presence of nanoparticles increases the corrosion resistance of the prepared electrodes. These substrates can be used as electrochemical sensors due to their high electrical conductivity, and also as implants due to the antibacterial properties of both the TNT and AgNPs.