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Fabrication of Graphene with Actuate Carbon Made from Cow Dung As Electrode Material Forelectrochemical Sensor- a Biomedical Applications

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Fabrication of Graphene with Actuate Carbon Made from Cow Dung As Electrode Material Forelectrochemical Sensor- a Biomedical Applications FABRICATION OF GRAPHENE WITH ACTUATE CARBON MADE FROM COW DUNG AS ELECTRODE MATERIAL FORELECTROCHEMICAL SENSOR- A BIOMEDICAL APPLICATIONS PROJECT REFERENCE NO.: 40S_BE_1116 COLLEGE : K.L.E. INSTITUTE OF TECHNOLOGY, HUBBALLI BRANCH : DEPARTMENT OF ELECTRONICS AND COMMUNICATION ENGINEERING GUIDE : PROF. RAVI HOSAMANI DR. NAGARAJ P. SHETTI STUDNETS : MS. PUSHPA M. HONNATTI MS. ANUSHA S. CHIKKENAKOPPA MS. SNEHA S. PONARKAR MS. POOJA U. BHAT Objectives: Cow dung is one of the most abundant wastes generated on earth and has been traditionally used as fertilizer and fuel in most of the developing countries. In this study activated carbon is synthesized from cow dung by a modified chemical activation method, where partially carbonized cow dung is treated with KOH in different ratio. With unique and highly desirable morphology, chemical/thermal stability and electrochemical properties, the graphene-based materials are paving way to the implementation of mediator less electrochemical detection schemes with direct electron transfer. Modification of the electrode surface using graphene nanocomposites by voltammetric techniques, like cyclic voltammetry (CV), linear sweep voltammetry (LSV), differential pulse voltammetry (DPV), square wave voltammetry (SWV) etc. Optimization of electrochemical parameters like supporting electrolyte pH, accumulation time, modifier amount, temperature effect, scan rate for the determination. Analytical applications in Pharmaceutical Formulations and Biological sample analysis. Introduction: Electro-analytical methods are the techniques employed in analytical chemistry to study an analyte by measuring electrical quantities such as current, potential and relating them to the chemical parameters. These methods are classified into three main categories, potentiometry (the difference in the electrode potential is measured) colorimetry (the cell’s current is measured over time) and voltammetry (the current is measured while actively altering potential). Thetype of electrical signal used for the quantification defines distinction between various voltammetric techniques. The branch of electrochemistry which now called as voltammetry was developed from discovery of polarography in 1922 by the Czech chemist Jaroslav Heyrovsky for which he received Nobel prize in chemistry.Earlyvoltammetric techniques had many problems, limiting to their viability for everyday use in analytical chemistry. In 1942 Hickling built the first three electrodes potentiostat. The 1960’s and 1970’s saw many advances in the theory, instrumentation, and the introduction of computer added and controlled systems which improved sensitivity and created new analytical methods. Industry responded with the production of potentiostat, various types of electrodes, and cells that could be effectively used in analytical work. Mefenamic Mefenamic acid is a non-steroidal anti-inflammatory medication.It is prescribed to relieve inflammation, swelling, stiffness, pain and fever. It is of particular use in arthritic and muscular conditions, and for broad spectrum pain relief, including headache, menstrual pain and discomfort, and dental pain.Mefenamic acid is also used for the treatment of excessive menstrual bleeding.This medication does not cure the underlying condition responsible for pain or inflammation, but simply keeps the symptoms under control.Mefenamic acid may irritate or even damage your stomach. To reduce this, it is advised to take this medication with food.This risk increases the longer you take this medication, or if you are also taking corticosteroid medications such as prednisone, anticoagulants (blood thinning medication) such as warfarin, or if you smoke or consume alcohol while being treated with mefenamic acid. Different techniques in voltammetry Voltammetry is a category of electroanalytical methods used in analytical chemistry and various industrial processes. Types of voltammetry Linear sweep voltammetry It is a voltammetric method where the current at a working electrodeis measured while the potential between the working electrode and a reference electrode is swept linearly in time. Staircase voltammetry In staircase voltammetry the potential sweep is a series of stair steps. The current is measured at the end of each potential change, right before the next, so that the contribution to the current signal from the capacitive charging current is reduced. Squarewave voltammetry In a squarewavevoltammetric experiment, the current at a (usually stationary) working electrode is measured while the potential between the working electrode and a reference electrode is swept linearly in time. Cyclic voltammetry A voltammetric method that can be used to determine diffusion coefficients and half cell reduction potentials. Anodic stripping voltammetry A quantitative, analytical method for trace analysis of metal cations. The analyte is deposited (electroplated) onto the working electrode during a deposition step, and then oxidized during the stripping step. The current is measured during the stripping step. Cathodic stripping voltammetry A quantitative, analytical method for trace analysis of anions. A positive potential is applied, oxidizing the mercury electrode and forming insoluble precipitates of the anions. A negative potential then reduces (strips) the deposited film into solution. Adsorptive stripping voltammetry A quantitative, analytical method for trace analysis. The analyte is deposited simply by adsorption on the electrode surface (i.e., no electrolysis), then electrolyzed to give the analytical signal. Chemically modified electrodes are often used. How it works? The electrochemical cell, where the voltammetricexperiment is carried out, consists of a working (indicator) electrode, a reference electrode, and a counter (auxiliary) electrode. In general, an electrode provides the interface across which charge can be transferred or its effects felt. The electrochemical reaction mainly refers to the reaction occurring at the working electrode surface. The reduction or oxidation of a substance at the surface of a working electrode, at the appropriate applied potential, results in the mass transport of new material to the electrode surface and the generation of a current. Even though, the various types of voltammetric techniques may appear to be very different at first glance, their fundamental principles and applications derive from the same electrochemical theory. Application of voltammetric technique Cyclic voltammetry (CV) is widely used to study a variety of redox processes, for obtaining stability of reaction products, the presence of intermediates in oxidation-reduction reactions, electron transfer kinetics, and the reversibility of a reaction. CV can also be used to determine the electron stoichiometry of a system, the diffusion coefficient of an analyte, and the formal reduction potential, which can be used as an identification tool. In addition, because concentration is proportional to current in a reversible, Nernstian system, concentration of an unknown solution can be determined by generating a calibration curve of current versus concentration. It is gaining interest in the field of cellular biology where it is used to measure concentration of various chemicals in the cells of organisms, including living ones. In cases where the reaction is irreversible cyclic voltammetry will not give any additional data that linear sweep voltammetry would give us. DPV measurements can be used to study the redox properties of extremely small amounts of chemicals. Analysis The use of the voltammetric techniques is the basis of the comprehension of the laws concerning several electrochemical phenomena and has a great importance in several thecnological fields, like: - Research of corrosion proof materials .Research of new electrodic processes for chemical industries Production of new type of batteries that can store rapidly a great quantities of energy. One of the most important application of Voltammetry is the quantitative analysis of trace of drug at µg/L levels or less. Work carried out so far: Using the activated carbon obtained from cow dung modifier electrode was prepared. Behavior study with and witout using graphene for the modifier electrode versus the electrode prepared from artificial carbon(graphite powder) is studied using cyclic voltammetric technique to detect mefenamic acid. pH study is done using linear sweep voltammetry to detect the suitable pH for further work. Accumulation study using cyclic voltammetry is done to obtain the accumulation time at which highest peak is obtained. Using the accumulation time again pH study is repeated to know the appropriate pH at that accumulation time. Scan rate study is done using the proper pH and accumulation time that were previosly obtained. Concentration study is done for varios concentrations using square wave voltammetry technique. Interference due to various organic components is studied. Tablet analysis is done for meftol tablet. .
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