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Biosensor

  1. 1. NAST-626: Nanoelectronics and bioelectronics By: Sudama Chaurasiya M. Tech IInd Sem. (NAST) Submitted to: Dr. A. K. Viswanath “Center for Nanoscience and Technology” PONDICHERRY UNIVERSITY BIOSENSORS
  2. 2. CONTENTS • What is biosensors • History of biosensors • Elements of biosensors • Basic characteristics of biosensors • Biosensing techniques in biosensor • Types of biosensors • DNA based biosensors and their types • Biosensors on the nanoscale • Applications of biosensors • References
  3. 3. WHAT IS A BIOSENSOR? “A self-contained integrated device which is capable of providing specific quantitative or semi-quantitative analytical information using a biological recognition element which is in direct spatial contact with a transducer element.” (IUPAC) OR “Biosensors are analytical tools for the analysis of bio- material samples to gain an understanding of their bio- composition, structure and function by converting a biological response into a measurable response”.
  4. 4. FATHER OF BIOSENSORS The first and the most widespreadly used commercial biosensor: the blood glucose biosensor – developed by Leland C. Clark in 1962 Professor Leland C Clark (1918–2005)
  5. 5. HISTORY OF BIOSENSORS 1916: First report on immobilization of proteins : adsorption of invertase on activated charcoal 1922: First glass pH electrode 1956: Clark published his definitive paper on the oxygen electrode. 1962: First description of a biosensor: an amperometric enzyme electrodre for glucose (Clark) 1969: Guilbault and Montalvo – First potentiometric biosensor urease immobilized on an ammonia electrode to detect urea 1970: Bergveld – ion selective Field Effect Transistor (ISFET) 1975: Lubbers and Opitz described a fibre-optic sensor with immobilised indicator to measure carbon dioxide or oxygen.
  6. 6. 1975: First commercial biosensor ( Yellow springs Instruments glucose biosensor) 1975: First microbe based biosensor, First immunosensor 1976: First bedside artificial pancreas (Miles) 1980: First fibre optic pH sensor for in vivo blood gases(Peterson) 1982: First fibre optic-based biosensor for glucose 1983: First surface plasmon resonance (SPR) immunosensor 1984: First mediated amperometric biosensor:ferrocene used with glucose oxidase for glucose detection. 1987: Blood-glucose biosensor launched by MediSense ExacTech. HISTORY OF BIOSENSORS
  7. 7. 1990: SPR based biosensor by Pharmacia BIACore 1992: Hand held blood biosensor by i-STAT 1996: Launching of Glucocard 1998: Blood glucose biosensor launch by LifeScan FastTake 1998: Roche Diagnostics by Merger of Roche and Boehringer mannheim CURRENT: Quantom dots, nanoparicles, nanowire, nanotube, etc HISTORY OF BIOSENSORS
  8. 8. ELEMENTS OF BIOSENSOR
  9. 9. SAMPLE: The biological component or analyte which is under study. TRANSDUCER: A transducer is more generally defined as a device which converts energy from one form to another. Which is combination of, BIORECEPTOR: The sensitive biological element a biologically derived material or biomimetic component that interacts (binds or recognizes) the analyte under study. ELECTRICAL INTERFACES: The detector element (works in a physicochemical way; optical, piezoelectric, electrochemical, etc.) that transforms the signal resulting from the interaction of the analyte with the biological element into electrical signal form. ELECTRONIC SYSTEM: Combination of electronic devices i.e. Amplifier, signal processer and display device that are primarily responsible for the display of the results in a user-friendly way. ELEMENTS OF BIOSENSOR
  10. 10. 1. LINEARITY: Linearity of the sensor should be high for the detection of high substrate concentration. 2. SENSITIVITY: Value of the electrode response per substrate concentration. 3. SELECTIVITY: Chemicals Interference must be minimized for obtaining the correct result. 4. RESPONSE TIME: Time necessary for having 95% of the response. BASIC CHARACTERISTICS OF A BIOSENSOR
  11. 11. Fluorescence DNA Microarray SPR Surface plasmon resonance Impedance spectroscopy SPM (Scanning probe microscopy, AFM, STM) QCM (Quartz crystal microbalance) SERS (Surface Enhanced Raman Spectroscopy) Electrochemical TYPICAL SENSING TECHNIQUES FOR BIOSENSORS
  12. 12. TYPES OF BIOSENSORS 1. Calorimetric Biosensor 2. Piezo-electric Biosensor 3. Electrochemical Biosensor 4. Potentiometric Biosensor 5. Optical Biosensor
  13. 13. CALORIMETRIC BIOSENSORS If the enzyme catalyzed reaction is exothermic, two thermistors may be used to measure the difference in resistance between reactant and product and, hence, the analyte concentration. PIEZO-ELECTRIC BIOSENSORS Piezo-electric devices use gold to detect the specific angle at which electron waves are emitted when the substance is exposed to laser light or crystals, such as quartz, which vibrate under the influence of an electric field. The change in frequency is proportional to the mass of absorbed material.
  14. 14. ELECTROCHEMICAL BIOSENSORS  For applied current: Movement of e- in redox reactions detected when a potential is applied between two electrodes. POTENTIOMETRIC BIOSENSOR For voltage: Change in distribution of charge is detected using ion-selective electrodes, such as pH-meters.
  15. 15. OPTICAL BIOSENSORS Colorimetric for color Measure change in light adsorption Photometric for light intensity Photon output for a luminescent or fluorescent process can be detected with photomultiplier tubes or photodiode systems.
  16. 16. DNA BASED BISENSOR  Motivated by the application to clinical diagnosis and genome mutation detection  PRINCIPLE OF DNA BIOSENSORS NUCLEIC ACID HYBRIDIZATION • Reannealing between the ssDNAs from different sources Perfect match • stable dsDNA, strong hybridization One or more base mismatches • weak hybridization
  17. 17.  Steps involved in electrochemical DNA hybridization biosensors: 1. Formation of the DNA recognition layer 2. Actual hybridization event 3. Transformation of the hybridization event into an electrical signal  Types DNA Biosensors •Electrodes •Chips •Crystals DNA BASED BISENSOR
  18. 18. Steps involved in electrochemical DNA hybridization biosensors:
  19. 19. TYPES DNA BIOSENSORS
  20. 20. BIOSENSORS ON THE NANOSCALE  Molecular sheaths around the nanotube are developed that respond to a particular chemical and modulate the nanotube's optical properties.  A layer of olfactory proteins on a nanoelectrode react with low-concentration odorants (SPOT-NOSED Project). Doctors can use to diagnose diseases at earlier stages.  Nanosphere lithography (NSL) derived triangular Ag nanoparticles are used to detect streptavidin down to one picomolar concentrations.  Anti-body based piezoelectric nanobiosensor to be used for anthrax, HIV, hepatitis detection.
  21. 21. APPLICATIONS OF BIOSENSORS  Food Analysis  Study of biomolecules and their interaction  Drug Development  Crime detection  Medical diagnosis (both clinical and laboratory use)  Environmental field monitoring  Quality control  Industrial Process Control  Detection systems for biological warfare agents  Manufacturing of pharmaceuticals and replacement organs
  22. 22. APPLICATIONS OF BIOSENSORS
  23. 23. REFERENCES 1. “Whole cell- and protein-based biosensors for the detection of bioavailable heavy metals in environmental samples” by Philippe Corbisiera, Daniel van der Leliea, at al. ELSEVISER Analytica Chimica Acta 387 (1999) 235-244. 2. “DNA BASED BIOSENSORS” By Zhai Iuni-Iui, Cui hong and Yang Yuifu, ELSEVISER Biotechnology Advances, Vol. 15. No. 1. pp. 43-58.1997. 3. “BIOSENSORS” by Frieder Schelfer and Florian Schubert Akademie der Wissenscha fien, Zentralinstitut fur Molekularbiologie, Robert-Riissle-Strasse lO,0-1115 Berlin-Buck Germany ELSEVIER Amsterdam - London - New York -Tokyo 1992

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