1,721,000 research outputs found
Paper-Based Electrochemical (Bio)Sensors for the Detection of Target Analytes in Liquid, Aerosol, and Solid Samples
Full text linkThe last decade has been incredibly fruitful in proving the multifunctionality of paper for delivering innovative electrochemical (bio)sensors. The paper material exhibits unprecedented versatility to deal with complex liquid matrices and facilitate analytical detection in aerosol and solid phases. Such remarkable capabilities are feasible by exploiting the intrinsic features of paper, including porosity, capillary forces, and its easy modification, which allow for the fine designing of a paper device. In this review, we shed light on the most relevant paper-based electrochemical (bio)sensors published in the literature so far to identify the smart functional roles that paper can play to bridge the gap between academic research and real-world applications in the biomedical, environmental, agrifood, and security fields. Our analysis aims to highlight how paper's multifarious properties can be artfully harnessed for breaking the boundaries of the most classical applications of electrochemical (bio)sensors
Facile development of cost effective and greener for all solid-state supercapacitor on paper substrate
No full textThe introduction of paper-based platforms for developing novel energy storage devices such as supercapacitors (SCs) highlights new promising opportunities in the field of flexible electronics. Herein, the use of paper-based substrate has shown reduced manufacturing cost and simplified coating process by screen-printing technology, as well as an improvement of the multilayer structure adhesion. The SC manufactured with Graphite ink mixed with Carbon Black (CB)/Prussian blue (PB) at different weight ratios (0, 3, 4, 5, 7, and 10 wt %) shows good performances. An optimum weight ratio of carbon black/prussian blue. 4 wt % is consistent with the following features: i) specific capacitance of 253 mF/cm2 at 0.01 V/s, ii) specific energy density of 0.5 mWh/cm2, iii) specific power density of 0.1 mW/cm2, and iv) good cycling stability (94%) after 5000 cycles. The proposed fabrication approach exhibits a simple scale-up, a low environmental impact and a decrease of manufacturing costs: it provides self-supporting electrodes based on a mixture of graphite ink and CB/PB nanocomposite
Carbon Black-Modified Electrodes Screen-Printed onto Paper Towel, Waxed Paper and Parafilm M®
Full text linkHerein, we evaluated the use of paper towel, waxed paper, and Parafilm M-(R) (Heathrow Scientific, Vernon Hills, IL, USA) as alternative substrates for screen-printed sensor manufacturing. Morphological study was performed to evaluate the adhesion of the ink on these uncommon substrates, as well as the morphology of the working electrode. The electrochemical characterization was carried out using ferricyanide/ferrocyanide as redox couple. To enhance the electrochemical properties of the developed sensors, the nanomaterial carbon black was used as nanomodifier. The modification by drop casting of the working electrode surface, using a stable dispersion of carbon black, allows to obtain a sensor with improved electrochemical behavior in terms of peak-to-peak separation, current intensity, and the resistance of charge transfer. The results achieved confirm the possibility of printing the electrode on several cost-effective paper-based materials and the improvement of the electrochemical behavior by using carbon black as sustainable nanomaterial
Medium-distance affordable, flexible and wireless epidermal sensor for pH monitoring in sweat
No full textIn the last decade, wearable sensors have gained a key role on biomedical research field for reliable health state monitoring. A wide plethora of physics marker sensors is already commercially available, including activity tracker, heart rate devices, and fitness smartwatch. On the contrary, wearable and epidermal sensors for chemical biomarker monitoring in several biofluids are not ready yet. Herein, we report a wireless and flexible epidermal device for pH monitoring in sweat, fabricated by encompassing a screen-printed potentiometric sensor, an integrated circuit, and antenna embedded onto the same Kapton substrate. An iridium oxide film was electrodeposited onto the graphite working electrode providing the pH sensitive layer, while the integrated circuit board allows for data acquisition and storing. Furthermore, a radio frequency identification antenna surrounding the entire system enables data transmission to an external reader up to nearly 2 m in the most favourable case. The potentiometric sensor was firstly characterised by cyclic voltammetry experiments, then the iridium oxide electrodeposition procedure was optimised. Next, the sensor was tested toward pH detection in buffer solutions with a near-Nernstian response equal to − 0.079 ±0.002 V for unit of pH. Interference studies of common sweat ions, including Na+, K+and Cl−, showed any influence on the pH sensor response. Finally, the integrated epidermal device was tested for real-time on-body pH sweat monitoring during a running activity.
Data recorded for a running subject were wireless transmitted to an external receiver, showing a pH value close to 5.5, in agreement with value obtained by pH-meter reference measurement
Paper as an ecodesigned and smart material for sample preparation integrated with electrochemical (bio)sensors
Full text linkSince 2009, paper-based electrochemical biosensors have demonstrated several additional features in analytical chemistry thanks to their capability to manage the fluids by pump-free microfluidics, easily preconcentrate the target analytes, treat the sample with a task-free approach, and detect the target analyte with high sensitivity and accuracy. Herein, we point out the use of paper as a functional material for sample preparation, addressing easily and in a sustainable way the fluid sample management, filtration, separation, centrifugation, chemical sample treatment, and reagent addition. The use of paper for sample preparation in the electrochemical (bio)sensor field is shed light for the first time in a dedicated review. The overriding goal is to highlight the advantages of these cost-effective, environmentally friendly, and easy-to-use devices for smart preparation procedures and accurate electrochemical detection of the target analytes in several fields, including biomedical, environmental, and agrifood
A lab-on-a-tip approach to make electroanalysis user-friendly and de-centralized: Detection of copper ions in river water
Full text linkThe development of portable and user-friendly sensing platforms is a hot topic in the field of analytical chemistry. Among others, electroanalytical approaches exhibit a high amenability for reaching this purpose, i.e. the commercial strips for diabetes care are an obvious success. However, providing fully-integrated and user-friendly methods is the leitmotiv. In this work we evaluate the use of a disposable pipette tip, opportunely configured, to realize the first example of lab-on-a-tip. The combination of a pipette tip, wire electrodes, and cotton wool filter, highlights the suitability of producing a novel one-shot electroanalytical platform that does not require expertise-required tasks. To demonstrate the feasibility of this novel method, copper (Cu2+) is detected in water samples by means of anodic stripping voltammetry. The quantification is performed directly into the tip that contains a cotton wool filter: the filter has the double function of purifying the matrices from gross impurities and releasing all the pre-loaded reagents necessary for the assay. After optimizing the experimental parameters, the lab-on-a-tip was capable of detecting Cu2+ linearly up to 300 μg/L with a detection limit of 6.3 μg/L. The effectiveness of the platform was confirmed by testing 50, 100, and 150 ppb Cu-spiked river water sample with recovery value comprised between 92 and 103%
Sustainable materials for the design of forefront printed (bio)sensors applied in agrifood sector
No full textThe search for sustainability has now become a duty for all those entities, nations or people who intend to combat poverty in the world, safeguard the environment and bridge the gap of disparities that unfortunately still exist between underdeveloped countries and medium-high developed nations.The agrifood sector plays an important role in this vision, and the development of sustainable analytical devices at low cost and easy to use for everyone, suitable for being adopted by those countries whose technological development does not allow them to take up expensive and sophisticated laboratory techniques, may constitute a contribution towards achieving the objectives listed above.In this review we illustrate some examples of electrochemical devices realized utilizing sustainable materials, such as paper, as support for disposable and reagent-free (bio)sensors applied to the monitoring of food quality and safety. We also mention the first applications of new carbonaceous materials obtained from the recycling of agrifood waste products, which promise interesting features for electrochemical applications. (C) 2020 Elsevier B.V. All rights reserved
A printed potentiometric sensor diving into a paper-based sampler for self-driven and volume-assisted detection of potassium ions in capillary blood
No full textA printed potentiometric sensor diving into a paper-based sampler for self-driven and volume-assisted detection of potassium ions in capillary bloo
Point-of-care devices for the detection of biomarkers of periprosthetic joint infection: State of the art and future perspectives
Full text linkOne of the main issues in the management of periprosthetic joint infection (PJI) is related to the correct diagnosis. Current guidelines for PJI infection are based on the 2018 Philadelphia Consensus Criteria which encompasses major and minor criteria, where minor criteria are based on the detection of selected biomarkers in synovial fluid or serum samples. In 2021, the European Bone and Joint Infection Society revised the aforementioned criteria; however, current methods require a long analysis time. In this overall scenario, we report the state of the art and the recent advances of point-of-care devices and implantable sensors for a new diagnostic approach in the diagnosis of PJI by quantifying well-established and emerging biomarkers in serum, blood, and synovial fluid. Finally, future challenges and perspectives have been reported, highlighting the relevance of sensing devices for paving a new concept of diagnosis and monitoring in the PJI field to solve this important issue
All-solid state ion-selective carbon black-modified printed electrode for sodium detection in sweat
Full text linkThe synergic combination of printed electronics and printed electrochemical sensors has recently emerged as a new route for developing smart chemical wearable devices applied to sweat monitoring. Sodium ion is one of electrolytes monitored in sweat to evaluate sweating level for electrolyte replacement recommendations. Herein, we report the development of new designed screen-printed electrodes, in which working electrode has been easily modified by drop-casting with the nanomaterial carbon black and a selective membrane cocktail, and the reference electrode with a polyvinyl butyral-based membrane. Once optimised all conditions, the screen-printed electrochemical sensor demonstrated no aqueous layer formation between working electrode and selective membrane, long-term potential stability, good shelf life, and resistance to interferences from oxygen and light. The carbon black-based sensor allowed for the detection of sodium ions in range 10(-4) M e 1 M with a slope of 58 +/- 3 mV/decade and a detection limit of 63 mu M. The applicability for sweat analysis was evaluated by analysing three sweat samples collecting during running activity, obtaining concentrations of 44 +/- 4 mM, 55 +/- 6 mM, and 47 +/- 3 mM, values in agreements with sodium ions content in healthy people, as well as using artificial sweat with recovery values of 90 +/- 3%, 94 +/- 2%, and 94 +/- 5%
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