Non-Invasive Electrochemical Biosensors Operating in Human Physiological Fluids

Non-invasive healthcare technologies are an important part of research and development nowadays due to the low cost and convenience offered to both healthcare receivers and providers. This work overviews the recent advances in the field of non-invasive electrochemical biosensors operating in secreted human physiological fluids, viz. tears, sweat, saliva, and urine. Described electrochemical devices are based on different electrochemical techniques, viz. amperometry, coulometry, cyclic voltammetry, and impedance spectroscopy. Challenges that confront researchers in this exciting area and key requirements for biodevices are discussed. It is concluded that the field of non-invasive sensing of biomarkers in bodily fluid is highly convoluted. Nonetheless, if the drawbacks are appropriately addressed, and the pitfalls are adroitly circumvented, the approach will most certainly disrupt current clinical and self-monitoring practices.

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Smartphone-Based NFC Potentiostat for Wireless Electrochemical Sensing

Applied Sciences ◽

10.3390/app11010392 ◽

2021 ◽

Vol 11 (1) ◽

pp. 392

Author(s):

Karnpimon Krorakai ◽

Supannika Klangphukhiew ◽

Sirinan Kulchat ◽

Rina Patramanon

Keyword(s):

Cyclic Voltammetry ◽

Point Of Care ◽

Low Cost ◽

Near Field ◽

Electrochemical Techniques ◽

Electrochemical Sensing ◽

Voltage Range ◽

Resource Limited ◽

Electrochemical Devices ◽

User Friendly

Most electrochemical sensing requires affordable, portable and easy-to-use electrochemical devices for use in point-of-care testing and resource-limited settings. This work presents the design and evaluates the analytical performance of a near-field communication (NFC) potentiostat, a flat card-sized electrochemical device containing a microchip for electrical analysis and an NFC antenna for smartphone connection. The NFC interface is a wireless connection between the microchip and smartphone to simplify measuring units and make the potentiostat into a passive operated device, running without a battery. The proposed potentiostat can perform the common electrochemical techniques including cyclic voltammetry and chronoamperometry with a current range and voltage range of ±20 µA and ±0.8 V. The performance of the NFC potentiostat is compared to a commercial benchtop potentiostat using ferricyanide as a standard solution. The results show that the NFC potentiostat is comparable to a commercial benchtop potentiostat for both cyclic voltammetry and chronoamperometry measurements. The application of the proposed potentiostat is demonstrated by measuring ascorbic acid concentration. As described, the NFC potentiostat, which is compatible with a smartphone, is low-cost, small in size and user-friendly. Thus, the device can be developed for on-site measurement to apply in various fields.

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Performance Evaluation of Miniature Integrated Electrochemical Cells Fabricated Using LTCC Technology

Sensors ◽

10.3390/s19061314 ◽

2019 ◽

Vol 19 (6) ◽

pp. 1314 ◽

Cited By ~ 1

Author(s):

Paulina Szymanowska ◽

Damian Nowak ◽

Tomasz Piasecki

Keyword(s):

Cyclic Voltammetry ◽

Electrochemical Impedance Spectroscopy ◽

Impedance Spectroscopy ◽

Protein Adsorption ◽

Materials Science ◽

Electrochemical Impedance ◽

Electrochemical Techniques ◽

Electrochemical Cells ◽

Transfer Resistance ◽

Relative Change

Miniaturized and integrated analytical devices, including chemical sensors, are at the forefront of modern analytical chemistry. The construction of novel analytical tools takes advantage of contemporary micro- and nanotechnologies, as well as materials science and technology. Two electrochemical techniques were used in experiments: electrochemical impedance spectroscopy and cyclic voltammetry. The goal of this study was to investigate electron transfer resistance in a model solution containing Fe 2 + / 3 + ions and protein adsorption using integrated electrochemical cells with different geometry. Tests performed at various Fe 2 + / 3 + concentration allowed to verify that these cells work properly. The influence of bovine serum albumin adsorbing to the surface of the integrated electrochemical cells was investigated. In electrochemical impedance spectroscopy, the value of R c t increased with protein adsorption and the relative change of R c t was in range 21% to 55%. In cyclic voltammetry the decreasing amperometric response of the working electrode was used as evidence of protein adsorption on the electrode.

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Portable Measurement Systems Based on Microcontrollers to Test Durability of Structures: Mini-Review

Frontiers in Built Environment ◽

10.3389/fbuil.2020.563857 ◽

2020 ◽

Vol 6 ◽

Author(s):

Crhistian C. Segura ◽

Johann F. Osma

Keyword(s):

Reinforced Concrete ◽

Visual Inspection ◽

Low Cost ◽

Electrochemical Techniques ◽

Embedded Sensors ◽

Reinforced Concrete Structures ◽

Future Trends ◽

Measurement Systems ◽

Steel Bars ◽

Electrochemical Devices

Corrosion presence is a recurrent concern in buildings and structures that use steel as their core or as reinforcement, due to the change of steel's properties caused by this phenomena. Therefore, methods to detect and quantify corrosion had been developed; some are based on electrical and electrochemical measurements. On reinforced concrete structures, sometimes there are exposed steel bars which are visible, but on those, a visual inspection could determine corrosion presence. There exist different options to measure the steel bars' corrosion and its level. The more straight forward consists of cutting through the concrete until the bar is exposed and connecting a measurement device there. A disadvantage of this technique is that steel has to be exposed to the environment during the measurement; as an alternative, novel contact-less electrochemical techniques are getting more popular. Recent advances in low-cost and portable electrochemical devices and embedded sensors can change how the structures are tested. Moreover, there is a discussion about how those devices, if developed for other fields as biosensors, can assist in other areas. This mini-review also gives some hints of what the future trends could be due to the combination of those areas.

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Printed Electrochemical Biosensors: Opportunities and Metrological Challenges

Biosensors ◽

10.3390/bios10110166 ◽

2020 ◽

Vol 10 (11) ◽

pp. 166

Author(s):

Emilio Sardini ◽

Mauro Serpelloni ◽

Sarah Tonello

Keyword(s):

Limit Of Detection ◽

Point Of Care ◽

Low Cost ◽

Basic Research ◽

Critical Discussion ◽

Detection Sensitivity ◽

Live Cells ◽

Electrochemical Biosensors ◽

Non Invasive ◽

Home Based

Printed electrochemical biosensors have recently gained increasing relevance in fields ranging from basic research to home-based point-of-care. Thus, they represent a unique opportunity to enable low-cost, fast, non-invasive and/or continuous monitoring of cells and biomolecules, exploiting their electrical properties. Printing technologies represent powerful tools to combine simpler and more customizable fabrication of biosensors with high resolution, miniaturization and integration with more complex microfluidic and electronics systems. The metrological aspects of those biosensors, such as sensitivity, repeatability and stability, represent very challenging aspects that are required for the assessment of the sensor itself. This review provides an overview of the opportunities of printed electrochemical biosensors in terms of transducing principles, metrological characteristics and the enlargement of the application field. A critical discussion on metrological challenges is then provided, deepening our understanding of the most promising trends in order to overcome them: printed nanostructures to improve the limit of detection, sensitivity and repeatability; printing strategies to improve organic biosensor integration in biological environments; emerging printing methods for non-conventional substrates; microfluidic dispensing to improve repeatability. Finally, an up-to-date analysis of the most recent examples of printed electrochemical biosensors for the main classes of target analytes (live cells, nucleic acids, proteins, metabolites and electrolytes) is reported.

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Ethanol electro-oxidation: Cyclic voltammetry, electrochemical impedance spectroscopy and galvanostatic oscillation

International Journal of Hydrogen Energy ◽

10.1016/j.ijhydene.2012.08.034 ◽

2012 ◽

Vol 37 (20) ◽

pp. 15156-15163 ◽

Cited By ~ 19

Author(s):

Lijuan Han ◽

Hua Ju ◽

Yanhui Xu

Keyword(s):

Cyclic Voltammetry ◽

Electrochemical Impedance Spectroscopy ◽

Impedance Spectroscopy ◽

Electrochemical Impedance ◽

Electro Oxidation

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The grades and freshness assessment of eggs based on density detection using machine vision and weighing sensor

Scientific Reports ◽

10.1038/s41598-021-96140-x ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Supakorn Harnsoongnoen ◽

Nuananong Jaroensuk

Keyword(s):

Machine Vision ◽

Vision System ◽

Low Cost ◽

Measuring System ◽

Coefficient Of Determination ◽

Water Displacement ◽

Non Invasive ◽

Future Potential ◽

Non Destructive ◽

Egg Freshness

AbstractThe water displacement and flotation are two of the most accurate and rapid methods for grading and assessing freshness of agricultural products based on density determination. However, these techniques are still not suitable for use in agricultural inspections of products such as eggs that absorb water which can be considered intrusive or destructive and can affect the result of measurements. Here we present a novel proposal for a method of non-destructive, non-invasive, low cost, simple and real—time monitoring of the grading and freshness assessment of eggs based on density detection using machine vision and a weighing sensor. This is the first proposal that divides egg freshness into intervals through density measurements. The machine vision system was developed for the measurement of external physical characteristics (length and breadth) of eggs for evaluating their volume. The weighing system was developed for the measurement of the weight of the egg. Egg weight and volume were used to calculate density for grading and egg freshness assessment. The proposed system could measure the weight, volume and density with an accuracy of 99.88%, 98.26% and 99.02%, respectively. The results showed that the weight and freshness of eggs stored at room temperature decreased with storage time. The relationship between density and percentage of freshness was linear for the all sizes of eggs, the coefficient of determination (R2) of 0.9982, 0.9999, 0.9996, 0.9996 and 0.9994 for classified egg size classified 0, 1, 2, 3 and 4, respectively. This study shows that egg freshness can be determined through density without using water to test for water displacement or egg flotation which has future potential as a measuring system important for the poultry industry.

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OP75 Facts And Values In Health Technology Assessment: The Case Of Non-Invasive Prenatal Testing

International Journal of Technology Assessment in Health Care ◽

10.1017/s0266462319001326 ◽

2019 ◽

Vol 35 (S1) ◽

pp. 19-19

Author(s):

Bart Bloemen ◽

Maarten Jansen ◽

Wouter Rijke ◽

Wija Oortwijn ◽

Gert Vanderwilt

Keyword(s):

Health Technology Assessment ◽

Technology Assessment ◽

Prenatal Testing ◽

Health Technology ◽

Non Invasive ◽

Relevant Evidence ◽

Healthcare Technologies ◽

General Abstract ◽

Structured Questionnaire

IntroductionHealth Technology Assessment (HTA) is where facts and values meet: the evidence that is considered relevant to the assessment of a technology depends on the value framework used. In the context of the European project VALIDATE (Values in doing assessments of healthcare technologies), we assessed to what extent this interplay between facts and values is acknowledged in HTA reports on non-invasive prenatal testing (NIPT). Our aim is to gain a better understanding of this fact-value relationship, and to contribute to the development of capacity for ethical analyses in HTA.MethodsFive reviewers independently analyzed HTA reports on NIPT, obtained from the National Institute for Health Research (NIHR) HTA database, by answering a structured questionnaire on: (i) arguments, values, and conclusions; (ii) relations between values and collected evidence; (iii) operationalizations of the values involved. Ethical argumentation was analyzed using the method of specifying norms. This method holds that for general, abstract ethical principles to reach concrete cases, principles need to be specified in such a way as to achieve maximal coherence between different value commitments and practice. The results of the analysis were discussed in joint meetings to arrive at a consensus on interpretation.ResultsOur results show that the pivotal role of values in defining what counts as relevant evidence and why, is rarely acknowledged. The same holds for the importance of specifying values as a means to achieve greater coherence between the use of healthcare technologies and a range of values.ConclusionsThere is ample room for improvement in clarifying the role of values in HTA: they can serve to explain and justify what evidence is considered relevant to the assessment of a healthcare technology. Recognizing that abstract values need specification in order to reach concrete cases opens up new opportunities for exploring in what way values are affected by healthcare technologies.

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Review of Electrochemical DNA Biosensors for Detecting Food Borne Pathogens

Sensors ◽

10.3390/s19224916 ◽

2019 ◽

Vol 19 (22) ◽

pp. 4916 ◽

Cited By ~ 4

Author(s):

Qiaoyun Wu ◽

Yunzhe Zhang ◽

Qian Yang ◽

Ning Yuan ◽

Wei Zhang

Keyword(s):

Pathogen Detection ◽

Low Cost ◽

Electrochemical Techniques ◽

Ease Of Use ◽

Detection Methods ◽

Future Research ◽

Dna Biosensors ◽

Food Borne Pathogens ◽

Chip Technology ◽

Food Borne

The vital importance of rapid and accurate detection of food borne pathogens has driven the development of biosensor to prevent food borne illness outbreaks. Electrochemical DNA biosensors offer such merits as rapid response, high sensitivity, low cost, and ease of use. This review covers the following three aspects: food borne pathogens and conventional detection methods, the design and fabrication of electrochemical DNA biosensors and several techniques for improving sensitivity of biosensors. We highlight the main bioreceptors and immobilizing methods on sensing interface, electrochemical techniques, electrochemical indicators, nanotechnology, and nucleic acid-based amplification. Finally, in view of the existing shortcomings of electrochemical DNA biosensors in the field of food borne pathogen detection, we also predict and prospect future research focuses from the following five aspects: specific bioreceptors (improving specificity), nanomaterials (enhancing sensitivity), microfluidic chip technology (realizing automate operation), paper-based biosensors (reducing detection cost), and smartphones or other mobile devices (simplifying signal reading devices).

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