Low Cost Electrochemical Sensors for Silver, Chloride, Bromide and Iodide Ions

Low cost all solid state pressed pellet Ag+, halides and sulphide sensitive electrodes based on silver sulphide were fabricated. The electrodes have been tested and results compare favorably with commercial electrodes. Pure Ag2S electrode with internal silver metal contact was found to follow Nernstian equation from 1 x 10-1 to 1 x 10-5 M of silver ion with slope equal to 59.8 mV per decade change in concentration of Ag+ - ion. Electrodes fabricated from equimolar mixture of Ag2S and Ag - halide was found to be sensitive to the respective halide and silver ions. Iodide ion selective electrode prepared from a equimolar mixture of Ag2S and AgI was found to be selective to iodide ion with negligible interference from bromide and chloride ions. The potentiometric selectivity coefficient Kpot I,Br, Kpot I,Cl were found to be 1.77x10-2 and 7.94x10-3 respectively. All these electrodes were found to be selective to Ag+ ion with negligible interference with Kpot Ag, Hg equal to 1 x 10-5 Hg++ ion with selectivity coefficient. Keywords: Ion selective electrodes; Potentiometric selectivity coefficient; Silver sulphide. DOI: 10.3126/sw.v6i6.2631 Scientific World, Vol. 6, No. 6, July 2008 33-36

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Iodide Ion Sensor for Indirect Determination of As (III) in Water

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.117.93 ◽

2010 ◽

Vol 117 ◽

pp. 93-98

Author(s):

A. Nyachhyon ◽

A.P. Yadav ◽

Krishna Manandhar ◽

Raja Ram Pradhananga

Keyword(s):

Polycrystalline Material ◽

Low Cost ◽

Direct Determination ◽

Selectivity Coefficient ◽

Indirect Determination ◽

Iodide Ion ◽

Silver Sulphide ◽

Nernstian Slope ◽

Co Precipitation

A simple, low cost and portable iodide sensor for the indirect determination of As(III) has been developed from the polycrystalline material obtained by co-precipitation of silver sulphide and silver iodide from aqueous solution. The Ag2S-AgI sensor was found to behave well up to the iodide concentration of 1×10-6 M with a Nernstian slope 57.5 mV per decade change in concentration. The selectivity coefficient of sensor containing iodide ion in the presence of Br- and Cl- ions was found to be 1.77 × 10-2 and 7.94 × 10-3, respectively indicating that these ions do not interfere in the response of iodide sensor to iodide ion. The electrode was successfully used for the direct determination of iodide and indirect determination of As(III) by titrating with cerric ammonium sulphate at pH 2. The results obtained from this method are comparable to the existing methods for the estimation of As(III).

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potentiometric selectivity coefficient

IUPAC Compendium of Chemical Terminology ◽

10.1351/goldbook.p04791 ◽

2008 ◽

Keyword(s):

Selectivity Coefficient ◽

Potentiometric Selectivity ◽

Potentiometric Selectivity Coefficient

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Preparation of halide sensors by means of co-precipitation of silver sulphide and silver halide

Journal of Nepal Chemical Society ◽

10.3126/jncs.v30i0.9390 ◽

2013 ◽

Vol 30 ◽

pp. 168-173 ◽

Cited By ~ 1

Author(s):

Armila Rajbhandari ◽

Krishna Manandhar ◽

Raja Ram Pradhananga

Keyword(s):

Response Time ◽

Linear Response ◽

Silver Halide ◽

Chemical Society ◽

Selectivity Coefficient ◽

Chloride Ions ◽

Iodide Ions ◽

Silver Sulphide ◽

Co Precipitation

Halide sensors have been prepared in the laboratory by means of co-precipitation of silver sulphide and silver halide and is used for the determination of iodide, bromide and chlorides ions. The iodide sensors show a Nernstian response in the concentration range of 10-1 to 10-6M iodide ions, bromide sensors show a linear response in the concentration range of 10-1 to 10-5M bromide ions while chloride sensors show linear response upto the concentration range of 10-4M chloride ions. The response time of all the electrodes, is < 1minute. The iodide sensors were found to be selective towards iodide ions in the presence of Cl- and Br- ions while bromide and chloride sensors interferred by iodide ions as indicated by selectivity coefficient values of 3.98 and 48.9 respectively. These sensors have been successfully applied for potentiometric titrations.DOI: http://dx.doi.org/10.3126/jncs.v30i0.9390Journal of Nepal Chemical Society Vol. 30, 2012 Page: 168-173 Uploaded date: 12/20/2013

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Deployment, Calibration, and Cross-Validation of Low-Cost Electrochemical Sensors for Carbon Monoxide, Nitrogen Oxides, and Ozone for an Epidemiological Study

Sensors ◽

10.3390/s21124214 ◽

2021 ◽

Vol 21 (12) ◽

pp. 4214

Author(s):

Christopher Zuidema ◽

Cooper S. Schumacher ◽

Elena Austin ◽

Graeme Carvlin ◽

Timothy V. Larson ◽

...

Keyword(s):

Carbon Monoxide ◽

Exposure Assessment ◽

Epidemiological Study ◽

Electrochemical Sensors ◽

Low Cost ◽

Puget Sound ◽

Ambient Air ◽

Ambient Air Pollution ◽

Calibration Models ◽

Study Participants

We designed and built a network of monitors for ambient air pollution equipped with low-cost gas sensors to be used to supplement regulatory agency monitoring for exposure assessment within a large epidemiological study. This paper describes the development of a series of hourly and daily field calibration models for Alphasense sensors for carbon monoxide (CO; CO-B4), nitric oxide (NO; NO-B4), nitrogen dioxide (NO2; NO2-B43F), and oxidizing gases (OX-B431)—which refers to ozone (O3) and NO2. The monitor network was deployed in the Puget Sound region of Washington, USA, from May 2017 to March 2019. Monitors were rotated throughout the region, including at two Puget Sound Clean Air Agency monitoring sites for calibration purposes, and over 100 residences, including the homes of epidemiological study participants, with the goal of improving long-term pollutant exposure predictions at participant locations. Calibration models improved when accounting for individual sensor performance, ambient temperature and humidity, and concentrations of co-pollutants as measured by other low-cost sensors in the monitors. Predictions from the final daily models for CO and NO performed the best considering agreement with regulatory monitors in cross-validated root-mean-square error (RMSE) and R2 measures (CO: RMSE = 18 ppb, R2 = 0.97; NO: RMSE = 2 ppb, R2 = 0.97). Performance measures for NO2 and O3 were somewhat lower (NO2: RMSE = 3 ppb, R2 = 0.79; O3: RMSE = 4 ppb, R2 = 0.81). These high levels of calibration performance add confidence that low-cost sensor measurements collected at the homes of epidemiological study participants can be integrated into spatiotemporal models of pollutant concentrations, improving exposure assessment for epidemiological inference.

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Nanocomposite Materials Based on Electrochemically Synthesized Graphene Polymers: Molecular Architecture Strategies for Sensor Applications

Chemosensors ◽

10.3390/chemosensors9060149 ◽

2021 ◽

Vol 9 (6) ◽

pp. 149

Author(s):

André Olean-Oliveira ◽

Gilberto A. Oliveira Brito ◽

Celso Xavier Cardoso ◽

Marcos F. S. Teixeira

Keyword(s):

Conducting Polymers ◽

Specific Surface ◽

Surface Area ◽

Specific Surface Area ◽

Electrochemical Sensors ◽

Structural Characteristics ◽

Low Cost ◽

Large Specific Surface Area ◽

Molecular Architecture ◽

Sensor Applications

The use of graphene and its derivatives in the development of electrochemical sensors has been growing in recent decades. Part of this success is due to the excellent characteristics of such materials, such as good electrical and mechanical properties and a large specific surface area. The formation of composites and nanocomposites with these two materials leads to better sensing performance compared to pure graphene and conductive polymers. The increased large specific surface area of the nanocomposites and the synergistic effect between graphene and conducting polymers is responsible for this interesting result. The most widely used methodologies for the synthesis of these materials are still based on chemical routes. However, electrochemical routes have emerged and are gaining space, affording advantages such as low cost and the promising possibility of modulation of the structural characteristics of composites. As a result, application in sensor devices can lead to increased sensitivity and decreased analysis cost. Thus, this review presents the main aspects for the construction of nanomaterials based on graphene oxide and conducting polymers, as well as the recent efforts made to apply this methodology in the development of sensors and biosensors.

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Molecularly Imprinted Polymers Combined with Electrochemical Sensors for Food Contaminants Analysis

Molecules ◽

10.3390/molecules26154607 ◽

2021 ◽

Vol 26 (15) ◽

pp. 4607

Author(s):

Dounia Elfadil ◽

Abderrahman Lamaoui ◽

Flavio Della Pelle ◽

Aziz Amine ◽

Dario Compagnone

Keyword(s):

Food Safety ◽

Molecularly Imprinted Polymers ◽

Electrochemical Sensors ◽

Low Cost ◽

Electrochemical Analysis ◽

Ease Of Use ◽

Electrochemical Sensing ◽

Food Contaminants ◽

Molecularly Imprinted ◽

Imprinted Polymers

Detection of relevant contaminants using screening approaches is a key issue to ensure food safety and respect for the regulatory limits established. Electrochemical sensors present several advantages such as rapidity; ease of use; possibility of on-site analysis and low cost. The lack of selectivity for electrochemical sensors working in complex samples as food may be overcome by coupling them with molecularly imprinted polymers (MIPs). MIPs are synthetic materials that mimic biological receptors and are produced by the polymerization of functional monomers in presence of a target analyte. This paper critically reviews and discusses the recent progress in MIP-based electrochemical sensors for food safety. A brief introduction on MIPs and electrochemical sensors is given; followed by a discussion of the recent achievements for various MIPs-based electrochemical sensors for food contaminants analysis. Both electropolymerization and chemical synthesis of MIP-based electrochemical sensing are discussed as well as the relevant applications of MIPs used in sample preparation and then coupled to electrochemical analysis. Future perspectives and challenges have been eventually given.

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Carbon nanomaterial hybrids via laser writing for high-performance non-enzymatic electrochemical sensors: a critical review

Analytical and Bioanalytical Chemistry ◽

10.1007/s00216-021-03382-9 ◽

2021 ◽

Author(s):

Marcel Simsek ◽

Nongnoot Wongkaew

Keyword(s):

Noble Metal ◽

Critical Review ◽

High Performance ◽

Carbon Nanomaterials ◽

Electrochemical Sensors ◽

Low Cost ◽

Three Dimensional ◽

Laser Writing ◽

Enzyme Mimicking ◽

Natural Enzyme

AbstractNon-enzymatic electrochemical sensors possess superior stability and affordability in comparison to natural enzyme-based counterparts. A large variety of nanomaterials have been introduced as enzyme mimicking with appreciable sensitivity and detection limit for various analytes of which glucose and H2O2 have been mostly investigated. The nanomaterials made from noble metal, non-noble metal, and metal composites, as well as carbon and their derivatives in various architectures, have been extensively proposed over the past years. Three-dimensional (3D) transducers especially realized from the hybrids of carbon nanomaterials either with metal-based nanocatalysts or heteroatom dopants are favorable owing to low cost, good electrical conductivity, and stability. In this critical review, we evaluate the current strategies to create such nanomaterials to serve as non-enzymatic transducers. Laser writing has emerged as a powerful tool for the next generation of devices owing to their low cost and resultant remarkable performance that are highly attractive to non-enzymatic transducers. So far, only few works have been reported, but in the coming years, more and more research on this topic is foreseeable. Graphical abstract

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Contribution of Nanomaterials to the Development of Electrochemical Aptasensors for the Detection of Antimicrobial Residues in Food Products

Chemosensors ◽

10.3390/chemosensors9040069 ◽

2021 ◽

Vol 9 (4) ◽

pp. 69

Author(s):

Valérie Gaudin

Keyword(s):

Signal Amplification ◽

Electrochemical Sensors ◽

Low Cost ◽

Food Products ◽

Animal Origin ◽

Screening Methods ◽

Chemical Methods ◽

Portable Instrumentation ◽

Physico Chemical ◽

Antimicrobial Residues

The detection of antimicrobial residues in food products of animal origin is of utmost importance. Indeed antimicrobial residues could be present in animal derived food products because of animal treatments for curative purposes or from illegal use. The usual screening methods to detect antimicrobial residues in food are microbiological, immunological or physico-chemical methods. The development of biosensors to propose sensitive, cheap and quick alternatives to classical methods is constantly increasing. Aptasensors are one of the major trends proposed in the literature, in parallel with the development of immunosensors based on antibodies. The characteristics of electrochemical sensors (i.e., low cost, miniaturization, and portable instrumentation) make them very good candidates to develop screening methods for antimicrobial residues in food products. This review will focus on the recent advances in the development of electrochemical aptasensors for the detection of antimicrobial residues in food products. The contribution of nanomaterials to improve the performance characteristics of electrochemical aptasensors (e.g., Sensitivity, easiness, stability) in the last ten years, as well as signal amplification techniques will be highlighted.

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Covalent Organic Frameworks for Electrochemical Sensors: Recent Research and Future Prospects

Current Analytical Chemistry ◽

10.2174/1573411017666210324141739 ◽

2021 ◽

Vol 17 ◽

Author(s):

Linyu Wang ◽

Shasha Hong ◽

Yuxi Yang ◽

Yonghai Song ◽

Li Wang

Keyword(s):

Specific Surface ◽

Electrochemical Sensors ◽

Gas Adsorption ◽

Low Cost ◽

High Sensitivity ◽

Crystalline Polymer ◽

Synthesis Methods ◽

High Porosity ◽

Covalent Organic Frameworks ◽

Covalent Bonds

Background: In recent years, electrochemical sensors are widely preferred because of their high sensitivity, rapid response, low cost and easy miniaturization. Covalent organic frameworks (COFs), a porous crystalline polymer formed by organic units connected by covalent bonds, have been widely used in gas adsorption and separation, drug transportation, energy storage, photoelectric catalysis, electrochemistry and other aspects due to their large specific surface, excellent stability, high inherent porosity, good crystallinity as well as structural and functional controllability. The topological structure of COFs can be designed in advance, the structural units and linkage are diversified, and the structure is easy to be functionalized, which are all beneficial to their application in electrochemical sensors. Methods: The types, synthesis methods, properties of covalent organic frameworks and some examples of using covalent organic frameworks in electrochemical sensors are reviewed. Results: Due to their characteristics of a large specific surface, high porosity, orderly channel and periodically arranged π electron cloud, COFs are often used to immobilize metal nanoparticles, aptamers or other materials to achieve the purpose of building electrochemical sensors with high sensitivity and good stability. Since the structure of COFs can be predicted, different organic units can build COFs with different structures and properties. Therefore, organic units with certain functional groups can be selected to build COFs with certain properties and used directly for electrochemical sensors. Conclusion: COFs have a good application prospect in electrochemical sensors.

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Hydrogenated Graphene Based Organic Thin Film Transistor Sensor for Detection of Chloride Ions as Corrosion Precursors

Applied Sciences ◽

10.3390/app12020863 ◽

2022 ◽

Vol 12 (2) ◽

pp. 863

Author(s):

Mounia Chakik ◽

Siziwe Bebe ◽

Ravi Prakash

Keyword(s):

Thin Film ◽

Graphene Oxide ◽

Environmental Factors ◽

Low Cost ◽

Chloride Ions ◽

Functionalized Graphene ◽

Organic Thin Film ◽

Surface Wetness ◽

Hydrogenated Graphene ◽

Monitoring Protocols

Corrosion monitoring and management has been at the center of structural health monitoring protocols due to its damaging effects on metallic structures. Current corrosion prevention and management programs often fail to include environmental factors such as Cl− ions and surface wetness. Early detection of these environmental factors can prevent the onset of corrosion and reduce repair and maintenance-related expenses. There is growing interest in creating solution-processed thin film environmental sensors with high sensitivity to corrosion precursors, low-cost fabrication, and small footprint, rendering them viable candidates for investigation as potential corrosion sensors that could be easily integrated into existing structures and screen printed or patterned directly into surface coatings. In this work, we have implemented C60-based n-type organic thin film transistors (OTFTs) with functionalized graphene oxide for humidity sensing and functionalized graphene nanoparticles for Cl− ion detection, using low-cost solution processing techniques. The reduced graphene oxide (rGO)-coated OTFT humidity sensor is designed for the qualitative estimation of surface moisture levels and high levels of humidity, and it exhibits a relative responsivity for dry to surface wetness transition of 122.6% to surface wetness, within a response time of 20 ms. We furthermore implemented an in-house synthesized hydrogenated graphene coating in conjunction with a second OTFT architecture for Cl− ions sensing which yielded a sensitivity of 4%/ppm to ultrafine ionic concentrations, over an order of magnitude lower than the range identified to cause corrosion in aircraft structures.

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