Biosensors are sensors designed for the detection of interesting biological signals. Biosensors usually yield a digital electronic signal which is proportional to the concentration of a specific biological or chemical

compound. Recent advances of the availability of micro-fabrication down to the micro and nano scale and inexpensive signal processing systems have made the development of a variety of novel biomedical sensors possible. The forecast in the biosensor revolution will dramatically change the medical,

pharmaceutical and environmental industries.

The basic design of a biosensor

1. The biocatalyst converts the substrate to product.
2. This reaction is determined by the transducer which converts it to an electrical signal.
3. The output from the transducer is amplified.
4. Processed.
5. Displayed.

The transducer can work a number of ways

1. The heat output (or absorbed) by the reaction (calorimetric biosensors)
2. Changes in the distribution of charges causing an electrical potential to be produced (potentiometric biosensors)
3. Movement of electrons produced in a redox reaction (amperometric biosensors)
4. Light output during the reaction or a light absorbance difference between the reactants and products (optical biosensors)
5. Effects due to the mass of the reactants or products (piezo-electric biosensors).

1. Isolate one biological parameter with little interference.
2. High sensitivity.
3. High accuracy.
4. Quick time response.
5. Biocompatibility.
6. Aging characteristics.
7. Small in size.
8. Ruggedness and robustness.
9. Low cost.

1. Integration of different technologies (electronics, chemistry, physics and biology).
2. Intelligent signal processing of information transmitted by the sensors.
3. Useful life time of some biosensors can be short. i.e. protein build up on the biological active interfaces.
4. Development of useful commercial products which utilize biosensors.
5. Scaling issues. When a system is reduced in size the changes in length, area and volume ratios determine the overall operation.
6. Finding more interfaces between biological materials and electronics.
7. Evaluation of new manufacturing procedures for large-scale production.
8. Integrated systems. Optimised performance of the sensor is supported by associated electronics, fluidics and separation technology.
9. Formulation of arrays of simple sensors for complex sensor tasks.
10. Sensitivity. Clinicians, food technologists and environmentalists all have an interest in generally increased sensitivity.
11. Stability. Disadvantage in exploiting the exquisite specificity and sensitivity of complex biological molecules is their inherent instability.
12. Selectivity. Isolating and measuring a particular biological compound with little inference from other compounds.
13. Anti-terror biosensors.
14. Micro-fabrication Processes.

Biosensors have been applied to a wide variety of analytical problems including in medicine, health care, environmental monitoring, drug discovery, the environment, food, process industries, security, defense, bioprocess monitoring and control. Personal monitoring devices such as glucose sensors for diabetics. Biosensors for Environmental Monitoring.

Prof. Ashok Mulchandani's Biosensors and Bioremediation Group

http://www.engr.ucr.edu/~adani

http://www.onr.navy.mil/sci_tech/personnel/cnb_sci/biosensors.htm

http://www.lsbu.ac.uk/biology/enztech/biosensors.html

Biotechnology Information Directory Section

http://www.cato.com/biotech/

http://www.cranfield.ac.uk/biotech/research/

http://orion1.paisley.ac.uk/marco/Enzyme_Electrode/Chapter1/HOME1.htm

1. Enzyme and other biosensors: evolution of a technology Higson, S.P.J.; Reddy, S.M.; Vadgama, P.M.; Engineering Science and Education Journal , Volume: 3 Issue: 1 , Feb. 1994 Page(s): 41 -48
2. Microfabrication techniques for chemical/biosensors Hierlemann, A.; Brand, O.; Hagleitner, C.; Baltes, H.; Proceedings of the IEEE , Volume: 91 Issue: 6 , June 2003 Page(s): 839 -863
3. Microbial biosensors for process and environmental control Karube, I.; Nakanishi, K.; Engineering in Medicine and Biology Magazine, IEEE , Volume: 13 Issue: 3 , June-July 1994 Page(s): 364 -374
4. Near-field optical sensors for particle shape measurements Nieuwenhuis, J.H.; Bastemeijer, J.; Bossche, A.; Vellekoop, M.J.;Sensors Journal, IEEE , Volume: 3 Issue: 5 , Oct. 2003 Page(s): 646 -651
5. Packaging for microelectromechanical and nanoelectromechanical systems Lee, Y.C.; Amir Parviz, B.; Chiou, J.A.; Shaochen Chen;Advanced Packaging, IEEE Transactions on [see also Components, Packaging and Manufacturing Technology, Part B: Advanced Packaging, IEEE Transactions on] , Volume: 26 Issue: 3 , Aug. 2003 Page(s): 217 -226
6. Fabrication of a disposable biosensor for Escherichia Coli O157:H7 detection Muhammad-Tahir, Z.; Alocilja, E.C.; Sensors Journal, IEEE , Volume: 3 Issue: 4 , Aug. 2003 Page(s): 345 -351
7. Is what you eat and drink safe? Detection and identification of microbial contamination in foods and water Lloyd, C.R.; Cleary, F.C.; Hea-Young Kim; Estes, C.R.; Duncan, A.G.; Wade, B.D.; Ellis, W.R., Jr.; Power, L.S.; Proceedings of the IEEE , Volume: 91 Issue: 6 , June 2003 Page(s): 908 -914
8. Detection of microorganisms and toxins with evanescent wave fiber-optic biosensors Lim, D.V.; Proceedings of the IEEE, Volume: 91 Issue: 6 , June 2003 Page(s): 902 -907
9. Time-dependent signatures of acoustic wave biosensors Hunt, W.D.; Stubbs, D.D.; Sang-Hun Lee; Proceedings of the IEEE , Volume: 91 Issue: 6 , June 2003 Page(s): 890 -901
10. Scaling issues in chemical and biological sensors Madou, M.J.; Cubicciotti, R.; Proceedings of the IEEE , Volume: 91 Issue: 6 , June 2003 Page(s): 830 -838
11. Electronic sensors with living cellular components Kovacs, G.T.A.; Proceedings of the IEEE , Volume: 91 Issue: 6 , June 2003 Page(s): 915 -929
12. New polyaniline-based potentiometric biosensor for pesticides detection Ivanov, A.N.; Evtugyn, G.A.; Lukachova, L.V.; Karyakina, E.E.; Budnikov, H.C.; Kiseleva, S.G.; Orlov, A.V.; Karpacheva, G.P.; Karyakin, A.A.; Sensors Journal, IEEE , Volume: 3 Issue: 3 , June 2003 Page(s): 333 -340
13. Emerging biomedical sensing technologies and their applications Cote, G.L.; Lec, R.M.; Pishko, M.V.; Sensors Journal, IEEE , Volume: 3 Issue: 3 , June 2003 Page(s): 251 -266
14. CMOS chip as luminescent sensor for biochemical reactions Ude Lu; Hu, B.C.-P.; Yu-Chuan Shih; Yuh-Shyong Yang; Chung-Yu Wu; Chiun-Jye Yuan; Ming-Dou Ker; Tung-Kung Wu; Yaw-Kuen Li; You-Zung Hsieh; Wensyang Hsu; Chin-Teng Lin; Sensors Journal, IEEE , Volume: 3 Issue: 3 , June 2003 Page(s): 310 -316
15. Sensor sensitivity training Peckerar, M.; Perkins, F.K.; Hodge-Miller, A.; Ehrlich, R.; Fertig, S.; Tender, L.; Circuits and Devices Magazine, IEEE , Volume: 19 Issue: 2 , March 2003 Page(s): 17 -24
16. Keeping watch on glucose Tamada, J.A.; Lesho, M.; Tierney, M.J.; Spectrum, IEEE , Volume: 39 Issue: 4 , April 2002 Page(s): 52 -57
17. An anthrax "smoke" detector Lester, E.D.; Ponce, A.; Engineering in Medicine and Biology Magazine, IEEE , Volume: 21 Issue: 5 , Sept.-Oct. 2002 Page(s): 38 -42
18. High-speed advanced sensors for bioterror weapons Kline, C.R., Jr.; Engineering in Medicine and Biology Magazine, IEEE , Volume: 21 Issue: 5 , Sept.-Oct. 2002 Page(s): 43 -47
19. Biological warfare canaries [biological attack detection] Aston, C.; Spectrum, IEEE , Volume: 38 Issue: 10 , Oct. 2001 Page(s): 35 -40
20. Fibre optic micro-optrode for dissolved oxygen measurements McCulloch, S.; Uttamchandani, D.; Science, Measurement and Technology, IEE Proceedings- , Volume: 146 Issue: 3 , May 1999 Page(s): 123 -127
21. Microfabricated cantilevers for measurement of subcellular and molecular forces Fauver, M.E.; Dunaway, D.L.; Lilienfeld, D.H.; Craighead, H.G.; Pollack, G.H.; Biomedical Engineering, IEEE Transactions on , Volume: 45 Issue: 7 , July 1998 Page(s): 891 -898
22. A high-sensitivity micromachined biosensor Baselt, D.R.; Lee, G.U.; Hansen, K.M.; Chrisey, L.A.; Colton, R.L.; Proceedings of the IEEE , Volume: 85 Issue: 4 , April 1997 Page(s): 672 -680
23. Molecular electronics: science and technology for the future Hong, F.T.; Engineering in Medicine and Biology Magazine, IEEE , Volume: 13 Issue: 1 , Feb.-March 1994Page(s): 25 -32