The document summarizes a group project on advances in ion selective electrodes. It discusses the different types of ion selective electrodes including glass membrane electrodes, solid state electrodes, liquid membrane electrodes, and gas sensing electrodes. It describes the key parameters that characterize ion selective electrodes such as sensitivity, selectivity, detection limit, and response time. The document also discusses various applications of ion selective electrodes for online, on-site, and in vivo potentiometric measurements. Recent advances in the applications of ion selective electrodes in areas such as agriculture, pollution control, food quality control, medical diagnostics, and industrial production are highlighted.
This document provides information on ion selective electrodes (ISEs). It discusses the history of ISE development from early pH electrodes to modern commercial applications. The basic components and functioning of ISEs are described, including the electrochemical cell setup with an ion selective membrane and reference electrode. Different types of membranes - glass, crystal, gas-sensing, and polymer - are outlined. Examples are given of specific ions that can be measured with different ISE configurations. The document concludes by discussing the mechanisms of ion exchange and selectivity in polymer membrane electrodes.
Electrogravimetry is a method used to separate and quantify ions of a substance, usually a metal, through electrolysis. The analyte solution is electrolyzed, causing the analyte to deposit on the cathode. The cathode is weighed before and after the experiment, and the mass difference is used to calculate the amount of analyte originally present. There are two types of electrogravimetry - constant current electrolysis, where the current is kept constant, and constant potential electrolysis, where the potential is kept constant. In both cases, the deposited analyte on the cathode is measured through changes in mass to determine the concentration in the original solution.
The document discusses ion selective electrodes (ISEs), including:
- The principle of ISEs is that a selective membrane allows only the intended ion to pass through, creating a potential difference.
- Types of ISEs include glass electrodes, liquid ion exchanger membranes, solid state membranes, and coated wire electrodes.
- ISEs have advantages like low cost, wide concentration range, robustness, and fast response times. Limitations include imprecision, interference, and limited lifetime.
- ISEs have many applications in fields, laboratories, medical/biological uses, and industrial processes due to their attributes.
Coulometry is an electrochemical method that measures the current needed to completely oxidize or reduce an analyte. There are two forms: controlled potential and controlled current. Controlled potential coulometry applies a constant potential to ensure 100% current efficiency and quantitative reaction of the analyte without interfering species. The decreasing current over time corresponds to decreasing analyte concentration. Controlled current coulometry passes a constant current, allowing more rapid analysis since current does not decrease over time. The total charge simply equals current multiplied by time. Coulometry provides precise, sensitive, and selective analysis of inorganic and organic compounds and can be adapted to automatic titration methods.
Ion selective electrodes (ISEs) selectively measure the activity of specific ions through a membrane without redox chemistry. Common ISEs include pH, calcium, and chloride electrodes. ISEs work by generating a potential difference as ions selectively bind and transport through membrane sites from high to low concentration, creating a measurable voltage. The voltage is proportional to ion activity and can identify ion concentrations. ISEs are useful for applications like pollution monitoring, agriculture, food processing, and biomedical analysis.
This document provides information on ion selective electrodes (ISEs). It discusses the history of ISE development from early pH electrodes to modern commercial applications. The basic components and functioning of ISEs are described, including the electrochemical cell setup with an ion selective membrane and reference electrode. Different types of membranes - glass, crystal, gas-sensing, and polymer - are outlined. Examples are given of specific ions that can be measured with different ISE configurations. The document concludes by discussing the mechanisms of ion exchange and selectivity in polymer membrane electrodes.
Electrogravimetry is a method used to separate and quantify ions of a substance, usually a metal, through electrolysis. The analyte solution is electrolyzed, causing the analyte to deposit on the cathode. The cathode is weighed before and after the experiment, and the mass difference is used to calculate the amount of analyte originally present. There are two types of electrogravimetry - constant current electrolysis, where the current is kept constant, and constant potential electrolysis, where the potential is kept constant. In both cases, the deposited analyte on the cathode is measured through changes in mass to determine the concentration in the original solution.
The document discusses ion selective electrodes (ISEs), including:
- The principle of ISEs is that a selective membrane allows only the intended ion to pass through, creating a potential difference.
- Types of ISEs include glass electrodes, liquid ion exchanger membranes, solid state membranes, and coated wire electrodes.
- ISEs have advantages like low cost, wide concentration range, robustness, and fast response times. Limitations include imprecision, interference, and limited lifetime.
- ISEs have many applications in fields, laboratories, medical/biological uses, and industrial processes due to their attributes.
Coulometry is an electrochemical method that measures the current needed to completely oxidize or reduce an analyte. There are two forms: controlled potential and controlled current. Controlled potential coulometry applies a constant potential to ensure 100% current efficiency and quantitative reaction of the analyte without interfering species. The decreasing current over time corresponds to decreasing analyte concentration. Controlled current coulometry passes a constant current, allowing more rapid analysis since current does not decrease over time. The total charge simply equals current multiplied by time. Coulometry provides precise, sensitive, and selective analysis of inorganic and organic compounds and can be adapted to automatic titration methods.
Ion selective electrodes (ISEs) selectively measure the activity of specific ions through a membrane without redox chemistry. Common ISEs include pH, calcium, and chloride electrodes. ISEs work by generating a potential difference as ions selectively bind and transport through membrane sites from high to low concentration, creating a measurable voltage. The voltage is proportional to ion activity and can identify ion concentrations. ISEs are useful for applications like pollution monitoring, agriculture, food processing, and biomedical analysis.
This document provides an overview of potentiometry and related electroanalytical techniques. It defines key concepts like reference electrodes, indicator electrodes, and salt bridges used in potentiometric cells. Equations for electrode potentials are described for various metal-metal ion systems. Membrane electrodes like glass pH electrodes are also summarized. The document concludes with brief discussions of potentiometric titration techniques and voltammetry methods.
Electrogravimetric analysis involves the quantitative deposition of an analyte onto an electrode through electrolysis. There are two main types: constant current electrolysis, where the current is kept constant and the potential varies, and controlled potential electrolysis, where the potential is kept constant to selectively deposit analytes. Electrogravimetric analysis can be used for quantitative analysis, separation, preconcentration of analytes, and electrosynthesis.
1. The document describes how to use flame atomic absorption spectroscopy to determine the concentration of calcium in bottled water samples.
2. Flame atomic absorption spectroscopy works by aspirating and atomizing liquid samples using a flame, then measuring the absorption of light at characteristic wavelengths to detect specific metals.
3. The technique requires samples to be aspirated and mixed with combustible gases and ignited in a flame between 2100-2800°C to atomize the metals, which will absorb light from a hollow cathode lamp at wavelengths specific to each metal.
This document summarizes voltammetry, an electrochemical method that uses a three-electrode system to obtain information about analytes. A voltage ramp is applied to the working electrode to reduce ions, while current is measured. Common types of voltammetry include cyclic, square wave, differential pulse, and stripping voltammetry. The working electrode potential is varied over time, while the reference electrode potential remains constant. Voltammetry can be used to determine metal ion concentrations, for wastewater analysis, and in various other applications due to its low detection limits and ability to handle high salt concentrations.
An ideal I.S.E. consists of a thin membrane across which only the
intended ion can be transported.
The transport of ions from a high conc. to a low one through a selective binding with some sites within the membrane creates a
This document provides an overview of radiochemical methods in activation analysis and isotopic dilution methods. It discusses three main types of radioanalytical methods: radiometric analysis, isotope dilution, and activation analysis. Activation analysis involves irradiating a sample with neutrons to induce radioactivity in atoms. This allows identification and quantification of elements in the sample by measuring the gamma or beta spectra of the radioactive elements. Isotopic dilution involves adding a known quantity of a radioactive isotope to the sample and using the dilution to calculate the amount of the non-radioactive substance.
1) The document discusses three methods for quantitative analysis in polarography: the calibration curve method, standard addition method, and pilot ion/internal standard method.
2) The calibration curve method involves creating a curve by measuring the current-voltage curves and wave heights of standard solutions and then determining the concentration of an unknown from that curve.
3) The standard addition method measures the wave heights of an unknown solution before and after adding a known amount of standard solution to calculate the unknown concentration using the Ilkovic equation.
4) The pilot ion method measures the relative wave heights of the unknown ion and a known "pilot ion", allowing the unknown concentration to be calculated using a ratio equation involving the two wave heights
Coulometry is an electroanalytical technique where the amount of electricity (in coulombs) required to complete an electrochemical reaction is measured. There are two main types - potentiostatic coulometry, where the potential is held constant, and coulometric titration with a constant current. The quantity of electricity is directly proportional to the amount of analyte and can be used to determine concentrations. Coulometry has applications in inorganic analysis, analysis of radioactive materials, microanalysis, and determination of organic compounds.
It is a well known fact that metal ions have a profound effect on cellular processes
The importance or the role that ions play in cellular activity can be gauged by the fact that most cells maintain a very critical Na+ & k+ balance between the extracellular and the intracellular spaces.
Any distribution in this critical balance is to the cellular metabolism through a drastic change in the osmotic pressure resulting in cellular swelling.
This document discusses potentiometry and ion selective electrodes. It begins by explaining that potentiometry measures the potential of an electrochemical cell under static conditions without drawing current. An ion selective electrode uses a selective membrane to measure the concentration of specific ions based on the potential difference between an indicator and reference electrode. The document then describes different types of reference electrodes, indicator electrodes, and ion selective electrodes like glass membrane, solid state, liquid membrane and gas sensing electrodes. It concludes by discussing applications in clinical chemistry, environmental analysis and food processing and advantages like speed and low cost and limitations like precision and interference issues.
This document discusses different types of electrodes used in electroanalytical chemistry. It describes inert electrodes like platinum, gold and graphite that do not participate in reactions, and reactive electrodes like zinc, copper and lead that actively participate in reactions. The document discusses various types of electrodes in detail, including glass electrodes, liquid ion exchanger membranes, solid state membranes, neutral carrier membranes, coated wire electrodes, and ion selective field effect transistors. It also outlines the principle, advantages, limitations and applications of ion selective electrodes.
Polarography is an electroanalytical technique that uses a dropping mercury electrode to determine the concentration of electroactive species in a solution. It works by measuring the current flowing between the indicator electrode and reference electrode as the voltage is increased. Polarography provides a polarogram graph of current vs voltage that shows diffusion currents and limiting currents to identify species present. It has advantages like simple sample handling, speed, sensitivity and limited use of organic solvents. Polarography is used in pharmaceutical analysis to determine concentrations of drugs, vitamins, hormones and other compounds.
This document discusses and compares inductively coupled plasma atomic emission spectroscopy (ICP-AES) and atomic absorption spectroscopy (AAS). It outlines the fundamental parts and techniques of each method including sample introduction, atomization, and detection. Key differences are described such as ICP-AES being able to analyze multiple elements simultaneously while AAS is single-element. The document also compares factors such as detection limits, linear ranges, analysis speeds, costs, ease of use, interferences, and applications.
Potentiometry, voltamemtry and conductometryapeksha40
This document discusses various electroanalytical techniques used in clinical laboratories including potentiometry, voltammetry, conductometry, and coulometry. Potentiometry measures electrical potential differences using ion-selective electrodes or redox electrodes. Voltammetry and amperometry are sensitive techniques that apply a voltage to induce an electrochemical reaction and measure the resulting current. Conductometry measures how well ions conduct electricity. Coulometry determines the amount of an electroactive substance by measuring the charge required for its oxidation or reduction reaction. The NOVA-8 analyzer is highlighted as an example that can test for electrolytes, pH, hematocrit, and other clinical analytes using these electroanalytical methods.
Atomic emission spectroscopy uses plasma sources like inductively coupled plasma to excite sample atoms and cause them to emit electromagnetic radiation of characteristic wavelengths. ICP is advantageous over flame sources because its higher temperatures of 6000-10000 K allow for excitation of more elements. The ICP system consists of an argon plasma torch and RF generator. Argon is used because it is inert and maintains high temperatures. ICP-AES provides rapid, multi-element analysis with low detection limits and matrix interferences. However, spectral interferences can still occur from overlapping emission lines.
This document provides an overview of atomic absorption spectroscopy (AAS). It discusses the history, principle, instrumentation, interferences and applications of AAS. The key components of an AAS include a light source such as a hollow cathode lamp, a sample atomizer like a flame, and a detector like a photomultiplier tube. AAS can be used to quantitatively analyze over 60 elements in solution by measuring the absorption of ground state atoms. Sensitivity can be improved using techniques like graphite furnace atomic absorption or hydride generation.
Voltammetry techniques measure current as a function of applied potential. Polarography uses a dropping mercury electrode, while cyclic voltammetry applies a potential that scans forward and backward. The resulting current-potential curve provides information about redox reactions. The Clark oxygen sensor is a common voltammetric sensor that measures oxygen levels using a platinum cathode and silver/silver chloride anode separated by an oxygen-permeable membrane. Combining voltammetry with spectroscopy allows study of reaction mechanisms.
Dc,pulse,ac and square wave polarographic techniques newBiji Saro
DC, pulse, AC, and square wave polarographic techniques are electroanalytical methods used to determine the concentration and nature of electroactive species in solutions. DC polarography applies a continuously increasing voltage to generate a sigmoidal current-voltage curve. Pulse polarography applies voltage pulses to eliminate non-faradaic currents and improve detection limits. AC polarography superimposes an AC potential on DC to measure the AC current component. Square wave polarography uses large amplitude square waves to sample current twice per cycle and plot the net current versus voltage. These techniques enable sensitive quantitative analysis down to micromolar and even nanomolar concentration levels.
The document discusses array detectors used in spectroscopy. It describes photodiode array detectors and charged coupled device (CCD) detectors. Photodiode array detectors contain an array of silicon photodiodes on a single chip that can simultaneously measure radiation intensities at all wavelengths. CCD detectors contain an array of linked capacitors that can transfer electric charges between neighboring capacitors, allowing detection of low intensity light signals. Both detector types offer advantages like low noise, wide spectral response, and simultaneous detection of emissions at different wavelengths.
A biosensor is a device that uses biological components like enzymes, antibodies, or living cells to detect analytes. It consists of a biological recognition element and a physicochemical transducer. A nanobiosensor is a biosensor that operates on the nanoscale. Some key applications of nanobiosensors include detecting DNA, proteins, cells, and biomarkers for medical diagnostics. They can also be used for environmental monitoring, food safety testing, and other areas. Despite their potential, commercialization of biosensors has faced challenges related to biomolecule immobilization, device sensitivity and reproducibility, and cost-effectiveness.
biosensor, modern, principles, technology, applications, working of sensor, types of sensor , nanomaterial, based biosensor(nanosensor) optical biosensor, flourescent biosensor, electrochemical and glucose biosensor, genetically encoded biosensor, microbial biosensor, cancer , references included, advantages and disadvantages also included.
This document provides an overview of potentiometry and related electroanalytical techniques. It defines key concepts like reference electrodes, indicator electrodes, and salt bridges used in potentiometric cells. Equations for electrode potentials are described for various metal-metal ion systems. Membrane electrodes like glass pH electrodes are also summarized. The document concludes with brief discussions of potentiometric titration techniques and voltammetry methods.
Electrogravimetric analysis involves the quantitative deposition of an analyte onto an electrode through electrolysis. There are two main types: constant current electrolysis, where the current is kept constant and the potential varies, and controlled potential electrolysis, where the potential is kept constant to selectively deposit analytes. Electrogravimetric analysis can be used for quantitative analysis, separation, preconcentration of analytes, and electrosynthesis.
1. The document describes how to use flame atomic absorption spectroscopy to determine the concentration of calcium in bottled water samples.
2. Flame atomic absorption spectroscopy works by aspirating and atomizing liquid samples using a flame, then measuring the absorption of light at characteristic wavelengths to detect specific metals.
3. The technique requires samples to be aspirated and mixed with combustible gases and ignited in a flame between 2100-2800°C to atomize the metals, which will absorb light from a hollow cathode lamp at wavelengths specific to each metal.
This document summarizes voltammetry, an electrochemical method that uses a three-electrode system to obtain information about analytes. A voltage ramp is applied to the working electrode to reduce ions, while current is measured. Common types of voltammetry include cyclic, square wave, differential pulse, and stripping voltammetry. The working electrode potential is varied over time, while the reference electrode potential remains constant. Voltammetry can be used to determine metal ion concentrations, for wastewater analysis, and in various other applications due to its low detection limits and ability to handle high salt concentrations.
An ideal I.S.E. consists of a thin membrane across which only the
intended ion can be transported.
The transport of ions from a high conc. to a low one through a selective binding with some sites within the membrane creates a
This document provides an overview of radiochemical methods in activation analysis and isotopic dilution methods. It discusses three main types of radioanalytical methods: radiometric analysis, isotope dilution, and activation analysis. Activation analysis involves irradiating a sample with neutrons to induce radioactivity in atoms. This allows identification and quantification of elements in the sample by measuring the gamma or beta spectra of the radioactive elements. Isotopic dilution involves adding a known quantity of a radioactive isotope to the sample and using the dilution to calculate the amount of the non-radioactive substance.
1) The document discusses three methods for quantitative analysis in polarography: the calibration curve method, standard addition method, and pilot ion/internal standard method.
2) The calibration curve method involves creating a curve by measuring the current-voltage curves and wave heights of standard solutions and then determining the concentration of an unknown from that curve.
3) The standard addition method measures the wave heights of an unknown solution before and after adding a known amount of standard solution to calculate the unknown concentration using the Ilkovic equation.
4) The pilot ion method measures the relative wave heights of the unknown ion and a known "pilot ion", allowing the unknown concentration to be calculated using a ratio equation involving the two wave heights
Coulometry is an electroanalytical technique where the amount of electricity (in coulombs) required to complete an electrochemical reaction is measured. There are two main types - potentiostatic coulometry, where the potential is held constant, and coulometric titration with a constant current. The quantity of electricity is directly proportional to the amount of analyte and can be used to determine concentrations. Coulometry has applications in inorganic analysis, analysis of radioactive materials, microanalysis, and determination of organic compounds.
It is a well known fact that metal ions have a profound effect on cellular processes
The importance or the role that ions play in cellular activity can be gauged by the fact that most cells maintain a very critical Na+ & k+ balance between the extracellular and the intracellular spaces.
Any distribution in this critical balance is to the cellular metabolism through a drastic change in the osmotic pressure resulting in cellular swelling.
This document discusses potentiometry and ion selective electrodes. It begins by explaining that potentiometry measures the potential of an electrochemical cell under static conditions without drawing current. An ion selective electrode uses a selective membrane to measure the concentration of specific ions based on the potential difference between an indicator and reference electrode. The document then describes different types of reference electrodes, indicator electrodes, and ion selective electrodes like glass membrane, solid state, liquid membrane and gas sensing electrodes. It concludes by discussing applications in clinical chemistry, environmental analysis and food processing and advantages like speed and low cost and limitations like precision and interference issues.
This document discusses different types of electrodes used in electroanalytical chemistry. It describes inert electrodes like platinum, gold and graphite that do not participate in reactions, and reactive electrodes like zinc, copper and lead that actively participate in reactions. The document discusses various types of electrodes in detail, including glass electrodes, liquid ion exchanger membranes, solid state membranes, neutral carrier membranes, coated wire electrodes, and ion selective field effect transistors. It also outlines the principle, advantages, limitations and applications of ion selective electrodes.
Polarography is an electroanalytical technique that uses a dropping mercury electrode to determine the concentration of electroactive species in a solution. It works by measuring the current flowing between the indicator electrode and reference electrode as the voltage is increased. Polarography provides a polarogram graph of current vs voltage that shows diffusion currents and limiting currents to identify species present. It has advantages like simple sample handling, speed, sensitivity and limited use of organic solvents. Polarography is used in pharmaceutical analysis to determine concentrations of drugs, vitamins, hormones and other compounds.
This document discusses and compares inductively coupled plasma atomic emission spectroscopy (ICP-AES) and atomic absorption spectroscopy (AAS). It outlines the fundamental parts and techniques of each method including sample introduction, atomization, and detection. Key differences are described such as ICP-AES being able to analyze multiple elements simultaneously while AAS is single-element. The document also compares factors such as detection limits, linear ranges, analysis speeds, costs, ease of use, interferences, and applications.
Potentiometry, voltamemtry and conductometryapeksha40
This document discusses various electroanalytical techniques used in clinical laboratories including potentiometry, voltammetry, conductometry, and coulometry. Potentiometry measures electrical potential differences using ion-selective electrodes or redox electrodes. Voltammetry and amperometry are sensitive techniques that apply a voltage to induce an electrochemical reaction and measure the resulting current. Conductometry measures how well ions conduct electricity. Coulometry determines the amount of an electroactive substance by measuring the charge required for its oxidation or reduction reaction. The NOVA-8 analyzer is highlighted as an example that can test for electrolytes, pH, hematocrit, and other clinical analytes using these electroanalytical methods.
Atomic emission spectroscopy uses plasma sources like inductively coupled plasma to excite sample atoms and cause them to emit electromagnetic radiation of characteristic wavelengths. ICP is advantageous over flame sources because its higher temperatures of 6000-10000 K allow for excitation of more elements. The ICP system consists of an argon plasma torch and RF generator. Argon is used because it is inert and maintains high temperatures. ICP-AES provides rapid, multi-element analysis with low detection limits and matrix interferences. However, spectral interferences can still occur from overlapping emission lines.
This document provides an overview of atomic absorption spectroscopy (AAS). It discusses the history, principle, instrumentation, interferences and applications of AAS. The key components of an AAS include a light source such as a hollow cathode lamp, a sample atomizer like a flame, and a detector like a photomultiplier tube. AAS can be used to quantitatively analyze over 60 elements in solution by measuring the absorption of ground state atoms. Sensitivity can be improved using techniques like graphite furnace atomic absorption or hydride generation.
Voltammetry techniques measure current as a function of applied potential. Polarography uses a dropping mercury electrode, while cyclic voltammetry applies a potential that scans forward and backward. The resulting current-potential curve provides information about redox reactions. The Clark oxygen sensor is a common voltammetric sensor that measures oxygen levels using a platinum cathode and silver/silver chloride anode separated by an oxygen-permeable membrane. Combining voltammetry with spectroscopy allows study of reaction mechanisms.
Dc,pulse,ac and square wave polarographic techniques newBiji Saro
DC, pulse, AC, and square wave polarographic techniques are electroanalytical methods used to determine the concentration and nature of electroactive species in solutions. DC polarography applies a continuously increasing voltage to generate a sigmoidal current-voltage curve. Pulse polarography applies voltage pulses to eliminate non-faradaic currents and improve detection limits. AC polarography superimposes an AC potential on DC to measure the AC current component. Square wave polarography uses large amplitude square waves to sample current twice per cycle and plot the net current versus voltage. These techniques enable sensitive quantitative analysis down to micromolar and even nanomolar concentration levels.
The document discusses array detectors used in spectroscopy. It describes photodiode array detectors and charged coupled device (CCD) detectors. Photodiode array detectors contain an array of silicon photodiodes on a single chip that can simultaneously measure radiation intensities at all wavelengths. CCD detectors contain an array of linked capacitors that can transfer electric charges between neighboring capacitors, allowing detection of low intensity light signals. Both detector types offer advantages like low noise, wide spectral response, and simultaneous detection of emissions at different wavelengths.
A biosensor is a device that uses biological components like enzymes, antibodies, or living cells to detect analytes. It consists of a biological recognition element and a physicochemical transducer. A nanobiosensor is a biosensor that operates on the nanoscale. Some key applications of nanobiosensors include detecting DNA, proteins, cells, and biomarkers for medical diagnostics. They can also be used for environmental monitoring, food safety testing, and other areas. Despite their potential, commercialization of biosensors has faced challenges related to biomolecule immobilization, device sensitivity and reproducibility, and cost-effectiveness.
biosensor, modern, principles, technology, applications, working of sensor, types of sensor , nanomaterial, based biosensor(nanosensor) optical biosensor, flourescent biosensor, electrochemical and glucose biosensor, genetically encoded biosensor, microbial biosensor, cancer , references included, advantages and disadvantages also included.
Biosensor and its Applications.
Biosensors are analytical devices that combine a biological component with a physicochemical detector to provide specific and sensitive detection of target analytes.
Importance: Biosensors have revolutionized the way we detect and monitor various substances, from biomarkers to environmental pollutants.
Biosensor is an leading Biological technology now. It is an application of Biotechnology. It makes laboratory tests more fast and easy to carry out. It is cost effective, more accurate precise, and have less errors.
The document describes the design and fabrication of an amperometric biosensor for glucose monitoring.
1) Microfabrication techniques were used to fabricate the sensor on a glass substrate, which consisted of a silver-silver chloride reference electrode, working electrode, and counter electrode.
2) Glucose oxidase was immobilized on the working electrode to catalyze the oxidation of glucose. When a potential was applied, the current produced was directly proportional to the glucose concentration.
3) Characterization of the reference electrode showed potential variations of less than 1mV between two identical electrodes fabricated for testing. Microfabrication allows mass production of low-cost, disposable glucose sensors.
This document defines a biosensor and describes its components and operating principles. A biosensor consists of a biological recognition element and physiochemical transducer. The biological element interacts selectively with the analyte of interest and the transducer converts the biological response into an electrical or optical signal. Common biological elements used include enzymes, antibodies, nucleic acids, and whole cells. Transducers can be electrical, optical, thermal, or piezoelectric. The signal is then related to the analyte concentration. Biosensors can be designed to detect a variety of analytes and find applications in food testing, healthcare diagnostics, bioprocess monitoring, and environmental analysis. Future work aims to improve biosensor immobilization techniques, sensitivity, selectivity,
A biosensor is a device that integrates a biological component with a physicochemical detector. There are three main components: the biological recognition element, transducer, and associated electronics. The biological element interacts selectively with the analyte. The transducer converts this interaction into a quantifiable signal like a current or voltage. The associated electronics then process and display the results. Common types of biosensors include electrochemical, optical, and ion channel switch biosensors which detect analytes through electrochemical reactions, light interactions, or ion flow respectively.
Nanowire Based FET Biosensors and Their Biomedical Applications. Fawad Majeed...Fawad Majeed
This document discusses nanowire-based biosensors and their applications in biomedicine. It begins by defining sensors and biosensors. Nanowires can be used as sensors due to their distinct electrical and optical properties. There are two main types of nanosensors: mechanical and chemical. Nanowire field-effect transistors can detect charged biomolecules through changes in conductivity. These sensors have been used to detect proteins, DNA, RNA and viruses by functionalizing the nanowire surface with specific receptors. While promising for detection, further improvements are needed for commercialization, such as enhanced sensitivity and simpler fabrication processes.
Biosensor is the Talk of The Day. It made possible, the conversion of yesteryear's cumbersome experiments to an easier, faster all the while improving its sensitivity and specificity. This article will help you to gain an acquaintance about it, its properties, etc.
This document provides an overview of various electrochemical techniques including electrochemistry, electrophoresis, and isoelectric focusing. It discusses the basic principles, components, types, procedures, advantages, disadvantages, applications and potential interferences of these techniques. Electrochemistry involves measuring current or voltage from ion activity and includes potentiometry, amperometry and coulometry. Electrophoresis separates charged particles in an electric field based on their size, charge and other factors. Isoelectric focusing separates molecules based on their isoelectric point.
This document summarizes different types of ion selective potentiometry electrodes, including liquid-liquid membrane electrodes, enzyme electrodes, and gas sensing electrodes. Liquid-liquid membrane electrodes use a water-immiscible liquid ion exchanger membrane to selectively measure ions like calcium. Enzyme electrodes immobilize enzymes like urease on an electrode to selectively measure enzyme substrates like urea. Gas sensing electrodes use a thin, porous, replaceable membrane to separate an analyte solution from an internal solution, allowing the electrode to selectively measure dissolved gases or ions by detecting pH changes.
This document defines biosensors and describes their key components and operating principles. It then discusses the main types of biosensors: piezoelectric, calorimetric, optical, and electrochemical. Electrochemical biosensors are further divided into conductimetric, amperometric, and potentiometric sensors. The document provides details on the principles, methods of operation, strengths, and weaknesses of each type.
A microelectronic pill was developed by researchers at Glasgow University to address limitations of earlier electronic capsules. The pill measures parameters like temperature, pH, conductivity, and dissolved oxygen as it passes through the gastrointestinal tract, transmitting data to an external receiver. It aims to detect diseases and abnormalities non-invasively. While providing several advantages over previous technologies, limitations remain around its inability to perform certain medical imaging or radiation treatments.
The document provides an overview of several lectures on excitable cells and neuronal biophysics. It discusses key topics including:
- The structure and properties of water and its role as a solvent.
- The structure of biological membranes and how they use lipid bilayers.
- How cells use protein pumps and ion channels to regulate ion concentrations and transport ions across membranes.
- Techniques for measuring ion fluxes including radiotracers, fluorescent dyes, and electrophysiology.
- Concepts from Newtonian mechanics like Newton's laws of motion that are relevant to understanding neuronal biophysics.
Biosensors combine a biological component with a detection device. They can detect analytes and provide information about biological systems. Biosensors have three main parts: (1) a biological recognition element (like enzymes, cells, nucleic acids, microbes) that interacts with the target analyte, (2) a transducer that converts this interaction into a measurable signal, and (3) a processing system. Biosensors are useful for monitoring parameters in various fields like healthcare, environmental protection, and food safety. They provide analytical tools to study bio-material structure, composition and function.
Methods in Electrochemical in chemistryKimEliakim1
This document discusses various electrochemical methods and their applications. It covers topics like potentiometry, types of electrochemical cells, reference electrodes, quantitative applications in clinical and environmental analysis, and potentiometric titrations. Ion selective electrodes are explained in detail, including how they work, types of analytes and electrodes, maintenance, and applications in various fields like analytical chemistry, clinical diagnostics, and environmental monitoring. Different types of voltammetry techniques are also introduced.
INTRODUCTION, DEFINATION OF ELECTROPHORESIS, ELECTROPHORESIS PRINCIPLE, TYPES OF ELECTROPHORESIS, FREE ELECTROPHORESIS, ZONE ELECTROPHORESIS,PAPER ELECTROPHORESIS, WORKING OF PAPER ELECTROPHORESIS, PROCEDURE FOR PAPER ELECTROPHORESIS, VISUALISATION, FACTORS AFFECTING SEPARATION OF MOLECULES, APPLICATIONS, working of paper electrophoresis ,procedure for paper electrophoresis ,visualisation ,factors affecting separation of molecules ,applications ,forensics ,dna fingerprinting ,molecular biology ,microbiology information about the organisms ,biochemistry mapping of cellular components ,paper electrophoresis is also used in study of sic ,hemoglobin abnormalities ,separation of blood clotting factors ,serum plasma proteins from blood sample ,used in separation and identification of alkaloids ,used for testing water samples ,toxicity of water ,drug industry to determine presence of illelgal drUGS
biosensors;components,types , applications and GMO biosensorsCherry
Biosensors are devices that helps to determine the concentration of an analyte in a sample. In this ppt, the definition, components, types, applications and GMO biosensors have been described.
Conductivity is a measure of how well an aqueous solution can conduct electricity, which depends on the concentration of ions in the solution from dissolved electrolytes. Conductivity is widely used in industrial applications such as water treatment, leak detection, clean-in-place monitoring, and desalination. There are two main types of conductivity sensors - contacting sensors with electrodes that directly contact the solution, and inductive sensors that induce currents without contacts using coils.
This document discusses biosensors. It defines a biosensor as a device that converts a biological signal into a measurable electrical signal. It notes that Professor Leland C. Clark is considered the father of biosensors. The document outlines the key parts of a biosensor including the bioreceptor, transducer, and signal processor. It describes different types of biosensors such as calorimetric, optical, resonant, piezoelectric, and electrochemical biosensors. Applications of biosensors include uses in food analysis, drug development, medical diagnostics, and environmental monitoring.
Similar to Advances in Ion Selective Electrodes(ISE) (20)
This document discusses infrared (IR) spectroscopy. It provides information on the basic principles of IR spectroscopy, sample preparation techniques, instrumentation including dispersive and Fourier transform IR spectrometers, data analysis and interpretation. Key points covered include how IR spectroscopy can be used to identify functional groups in molecules based on their characteristic absorption frequencies, and that each compound produces a unique IR spectrum that can be considered a "fingerprint" of its structure.
This document discusses various analytical techniques used in spectroscopy. It describes spectroscopy as the study of interaction between electromagnetic radiation and matter. There are different types of spectroscopy including absorption, emission, and scattering spectroscopy. Specific techniques are used to identify unknown substances, predict behavior of new materials, and qualitatively or quantitatively analyze chemical composition. The document provides examples of spectroscopy techniques and their applications in areas like determining organic structures and quantifying metal ions.
This document provides an overview of polymer chemistry course content including synthesis of polymers, characterization of polymer molecules, molecular weight determination, and polymer structures. It discusses different types of polymers such as thermoplastics, thermosets, elastomers, and their properties. The key topics covered are polymerization reactions, molecular weight averages, polymer configurations including isotactic, syndiotactic and atactic, nomenclature, and the importance of molecular weight on polymer properties.
The document discusses viscosity measurement using a Ubbelohde viscometer. It measures the flow time of a dilute polymer solution dropping between two levels to calculate viscosity values like relative viscosity, specific viscosity, reduced viscosity, and inherent viscosity. These viscosity designations can be related to the molecular weight of the polymer using equations like the Mark-Houwink-Sakurada equation. Precise viscosity measurements require a clean vertical viscometer and constant temperature control.
This document provides information about fatty acids and triglycerides. It discusses the structure, properties, and reactions of fatty acids, including their length, degree of saturation, and location of double bonds. Triglycerides are introduced as esters composed of glycerol and three fatty acid chains. Their physical properties depend on the fatty acid components, and they undergo hydrolysis, saponification, and hydrogenation reactions. The learning outcomes are to understand fatty acids and triglycerides, and distinguish between their physical and chemical properties.
This document summarizes key information about alkaloids. It discusses that alkaloids are nitrogen-containing organic compounds found in plants that have physiological effects. Common alkaloids like morphine, codeine, caffeine, and cocaine are mentioned. The characteristics, occurrence in plants, classification based on chemical structure, and examples of alkaloids used in modern medicine are described. The biosynthesis pathways of morphine and codeine from opium poppy are also summarized.
Au nanospheres and nanorods for enzyme-free electrochemical biosensor applica...Nur Fatihah
1) The document describes the synthesis of gold nanospheres and nanorods with different morphologies for use in enzyme-free electrochemical biosensors.
2) The electrocatalytic properties and stability of biosensors using different gold nanocrystal shapes were investigated. Au nanocrystals were attached to screen-printed electrodes and used to detect hydrogen peroxide.
3) Results showed that the electrocatalytic properties and sensitivity of the biosensors depended on the morphology of the gold nanocrystals used. Biosensors using different shaped gold nanocrystals were stable for over 68 days.
Au nanospheres and nanorods for enzyme-free electrochemical biosensor applica...
Advances in Ion Selective Electrodes(ISE)
1. GROUP 7
ADVANCES IN ION SELECTIVE
ELECTRODES(ISE)
GROUP MEMBERS:
YAAKOB BIN ABD RAZAK (154631)
AMIR BIN HASANUDIN (154046)
ASILAH BTE JAMIL (154423)
NOR HIDAYAT BINTI YUSOF (152356)
INTAN NORYANA BINTI AHMAD (153741)
NORSYAMIMI BINTI CHE SULAMAN (153504)
NUR SHUHADA BINTI MOHD MOKHTARUDDIN (153142)
NURUL FADZILLAH BINTI MOHD HATTA (152266)
FAZURA EMYZA BINTI ABD AZIZ (153819)
NUR FATIHAH BINTI ABAS (154120)
2. Preview
1) Introduction to Ion Selective Electrodes,ISE
2) Composition of ISE(Glass Membrane Electrode,Solid State
Electrode,Liquid Membrane Electrode,Gas Sensing Electrode)
3) Parameters of ISE(sensitivity,selectivity,detection limit and
response time)
4) Potentionmetric measurements of ISE(in vivo, on line,on site)
5) The Recent advance(application of ISE)
3. Ion selective electrodes(ISE)
-An ion-selective electrode (ISE), also known as a specific ion
electrode (SIE), is a transducer (or sensor) that converts the activity of
a specific ion dissolved in a solution into an electrical potential, which
can be measured by a voltmeter or pH meter.
-Several types of sensing electrodes are commercially available which
are Glass Membrane Electrode, Solid State Electrode, Liquid
Membrane Electrode,Gas Sensing Electrode
4. • Ion Selective Electrodes (including the most common pH electrode) work on the
basic principal of the galvanic cell .By measuring the electric potential generated
across a membrane by "selected" ions, and comparing it to a reference
electrode, a net charge is determined. The strength of this charge is directly
proportional to the concentration of the selected ion. The basic formula is given for
the galvanic cell:
Ecell = EISE - ERef
5. TYPES OF ION SELECTIVE
ELECTRODE (ISE)
•Glass Membrane Electrode
•Solid State Electrode
•Liquid Membrane Electrode
•Gas Sensing Electrode
6. GLASS MEMBRANE ELECTRODE
• Glass electrode are responsive to univalent cations
( H+ , Na+)
• The selectivity for this cation by varying the composition
of a thin ion sensitive glass membrane.
• Example: pH electrode
- used for pH measurement
- used as a transducer in various gas and biocatalytic
sensor, involving proton generating or consuming
reaction.
7. pH electrode
•Glass membrane manufactured from SiO2 with negatively
charged oxygen atom.
•Inside the glass bulb, a dilute HCl solution and silver wire
coated with a layer of silver chloride.
•The electrode is immersed in the solution and pH is
measured.
8. SOLID STATE ELECTRODE
Solid state electrode are selective primarily to
anions.
It may be a homogenous membrane electrode or
heterogeneous membrane electrode.
Homogenous membrane electrode: ion-selective
electrodes in which the membrane is a crystalline
material (AgI/Ag2S).
9. Heterogeneous membrane electrode: ion-selective
electrodes prepared of an active substance, or mixture
of active substances (silicone rubber or PVC).
Example: Fluoride ion selective electrode
10. LIQUID MEMBRANE ELECTRODE
Liquid membrane is a type of ISE based on water-
immiscible liquid substances produced in a polymeric
membrane used for direct potentiometric
measurement.
Used for direct measurement of several polyvalent
cations (Ca ion) as well as a certain anions.
11. Example: Ion Exchanger Electrode
•The polymeric membrane made of PVC to separate the
test solution from its inner compartment.
•Contains standard solution of the target ion.
•The filling solution contains a chloride salt for establishing
the potential of the internal Ag/AgCl wire electrode.
12. GAS SENSING ELECTRODE
Available for the measurement of ammonia, carbon
dioxide and nitrogen oxide.
This type of electrode consist of permeable
membrane and an internal buffer solution.
The pH of the buffer changes as the gas react with it.
13. The change is detected by a combination pH sensor
within the housing.
This type of electrode does not require an external
reference electrode.
14. Parameters of ISE
Sensitivity
Selectivity
Detection Limit
Response Time
15. Nikolsky-Eisenman equation,
Where
RT.ln10/F-Sensitivity(S)
kxy-selectivity coefficient
ax-activity of the ion, X
ay-activity of the interfering ion, Y
zx-charge of the primary ion, X
zy-charge on the interfering ion, Y
The ‘constant’-E0
16. Selectivity
An electrode used to measure primary ion X selectively
may also slightly responds to interference ion Y.
Selectivity coefficient, kxy,is used in ISE to distinguish the
ion X from ion Y in the same solution.
kxy is not constant and depends on several factors including
the concentration of both elements, the total ionic strength
of the solution, and the temperature.
The value of kxy, is defined by the Nikolsky-Eisenman
equation:
The smaller the value of kxy ,the greater is the electrode’s
preference for the primary ion, X.
17. Sensitivity
Ability to detect primary ion at the lower concentration.
Theoretical value of S=59mV,represents 100%
sensitivity.
The value of S varies with kxy
small value of kxy means that the electrode is more
sensitive to primary ion,X instead of interfering ion,Y.
18. Detection limit
Defined by the intersection of the two extrapolated linear
parts of the ion-selective calibration curve.
LOD ~ 10-5-10-6 M is measured for most ISE.
Observed LOD is often governed by the presence of other
interfering ions or impurities.
Metal buffers can be used to eliminate the effects which
lead to the contamination of very dilute solutions. May
reduce LOD to 10-10 M.
19.
20. Response time
From the time the ISE and a reference electrode are
dipped in the sample solution (or the time at which the
ion concentration in a solution in contact with ISE and a
reference electrode is changed ) to when the potential of
the cell becomes equal to its steady-state value within 1
[mV] or has reached 90% of the final value (in certain
cases also 63% or 95%).
The response time usually increases with decreasing
determinand concentration
21. Time constant of Rate of the charge-
the measuring Determinand transfer reaction
instrument diffusion through the across the
hydrodynamic layer membrane/solution
interface, which
results in charging of
the electrical double
layer at this interface
Rate of the exchange
reaction between the Factors
determinand in the influence
membrane and an
interferent in the response
time Dissolution of the
analyte membrane-active
component in the
analyte
Establishment of the Interferent
diffusion potential diffusion in the
across the membrane membrane
23. Meanings:
1) on-line : being in progress now.
2) on-site : taking place or located at the side.
3) in vivo : within a living organism.
24. ISE have been widely used as detectors in high-speed automated flow
analyzers such as air-segmented or flow injection systems for the high-speed
determination of physiologically important cationic or anionic electrolytes in
body fluids.
Example of flow injection
determination of physiologically
potassium in serum.
Several designs of low-volume potentiometric flow detectors
have been reported.
Flow-through
potentiometric cell design
25. Potentiometric microelectrodes are very suitable for in vivo real time
clinical monitoring of blood electrolytes, intracellular studies, in situ
environmental surveillance or industrial process control. For example
Simon’s group described the utility of a system for on-line measurement
of blood potassium ion concentration during an open-heart surgery.
Miniaturized catheter-type ISE sensors
such as implantable probe represent
the preferred approach for routine
clinical in vivo monitoring of blood
electrolyte.
Diamond's group developed an array of
miniaturized chloride, sodium, and
potassium ISEs for point-of-care
analysis of sweat in connection to non-
invasive diagnosis of cystic fibrosis.
Miniaturized catheter-type ISE sensor
27. Agriculture and Fishery Pollution Control
-Soil and fertilizer for -pH of acid rain, soil, surface water
Nitrate, Ammonium, -Contamination of surface water
Potassium to optimize the use of and ground water with ammonium
fertilizer. and nitrate
-Dissolved Oxygen and pH in ponds -Contamination of waste water with
for Cyanide, Cadmium, Mercury and
fish breeding. Copper
Industrial Production
Food and Quality Control
-Salinity and pH of Boiler
feed
Worldwide -Nitrate and Nitrite in meat and
application vegetables
water
-Chloride, Sodium, Nitrate and
-Cyanide in plating baths
Nitrite in
-Process (specific ions)
baby food.
-Cadmium in fish
Medical Diagnosis and Hygiene Control
-Potassium in urine
-Contamination in various ions.
28. Advantages of Ion Selective Electrode
(ISE) Technique
When compared to many other analytical techniques, Ion-
Selective Electrodes are relatively inexpensive and simple to
use and have an extremely wide range of applications and wide
concentration range.
Under the most favourable conditions, when measuring ions in
relatively dilute aqueous solutions and where interfering ions are
not a problem, they can be used very rapidly and easily.
They are particularly useful in applications where only an order
of magnitude concentration is required, or it is only necessary to
know that a particular ion is below a certain concentration level.
29. They are invaluable for the continuous monitoring of changes in
concentration for example in potentiometric titrations or monitoring
the uptake of nutrients, or the consumption of reagents.
They are particularly useful in biological/medical applications
because they measure the activity of the ion directly, rather than the
concentration.
ISEs are one of the few techniques which can measure both
positive and negative ions.
They are unaffected by sample colour or turbidity.
ISEs can be used in aqueous solutions over a wide temperature
range. Crystal membranes can operate in the range 0 C to 80 C
and plastic membranes from 0 C to 50 C.
30. Surface Plasmon Resonance (SPR)
Based on immunosensors for detection and monitoring of low-molecular-
weight analytes of biomedical, food and environmental fields.
SPR is a surface sensitive optical technique for monitoring biomolecular
interactions occurring in very close vicinity of a transducer (gold)
surface, and that has given it a great potential for studying surface-confined
affinity interactions without rinsing out unreacted or excess reactants in
sample solutions.
It allows real-time study of the binding interactions between a biomolecule
(antibody) immobilized on a transducer surface with its biospecific partner
(analyte) in solution without the need for labeling the biomolecules by
exploiting the interfacial refractive index changes associated with any
affinity binding interaction.
In general, an SPR immunosensor is comprised of several important
components: a light source, a detector, a transduction surface (usually
gold-film), a prism, biomolecule (antibody or antigen) and a flow system.
31. • The transduction surface is usually a thin gold-film (50–100 nm) on a
glass slide optically coupled to a glass prism through a refractive index
matching oil. In addition to gold, several metals can be used including
silver, copper and aluminium. However, gold is highly preferred due to its
chemical stability and free electron behaviour.