BIOSENSORS NATIONAL INSTITUTE OF SCIENCE & TECHNOLOGY Under the guidance of Mr. Vivek sharma Presented By Pramoda Padhy Roll no-(EI200117092) NATIONAL INSTITUTE OF SCIENCE & TECHNOLOGY Palur Hills,Berhampur-761008,Orissa,India

INTRODUCTION What Is a Biosensor? Biosensor = bioreceptor + transducer. The bioreceptor is a biomolecule that recognizes the target analyte whereas the transducer converts the recognition event into a measurable signal. Enzyme is a Bioreceptor Requirements for Sensors

Need for Biosensor Diagnostic Market The current climate of prevention the need for detection at increasingly lower limits is increasing in many diverse areas Clinical Testing clinical testing is one of the biggest diagnostic markets clinical testing products market in excess of 4000 million US$ in the 1990s Other Markets The medical arena (Technical Insights Inc.) with veterinary and agricultural applications

Specificity Speed Simplicity Continuous monitoring capability With biosensors, it is possible to measure specific analytes with great accuracy. Speed analyte tracers or catalytic products can be directly and instantaneously measured Simplicity receptor and transducer are integrated into one single sensor& the measurement of target analytes without using reagents is possible Continuous monitoring capability Biosensors regenerate and reuse the immobilized biological recognition element

Applications of Biosensor Health Care Measurement of Metabolites Market Potential Diabetes Insulin Therapy Artificial Pancreas Industrial Process Control Bioreactor Control Military Application Environmental Monitoring Air and Water Monitoring

Bioreceptor Molecules Enzymes Enzymes act as catalysts for biochemical reactions occurring in the cell Antibody Antibodies constitute about 20% of the total plasma protein and are collectively called immunoglobulin Receptor Protein Receptor proteins having specific affinity for hormones, antibodies, enzymes Other Possibilities

Transducers Conventional Transducers Piezoelectric Transducers Coniductimetry Capacitance Measurement Thermometry Enzyme Thermistor FET as a Transducer

Growth of Biosensor Biosensor Configurations Discriminative Membrane Sensitivity Requirements Immunoassay DNA Probe Evolution of Biosensors

Receptors Receptors at Membrane Hormone Receptors Smell Receptor Biological receptors are protein molecules most of them are bound to the cell membrane Hormone Receptors Many hormones released into the blood do not penetrate the cell membrane but react with specific receptors at the cell surface Smell Receptor taste and olfactory receptors are typical examples of this biospecific recognition process Light Receptor

Types of biosensor Glucose Biosensor Amperometric Biosensor Glucose biosensor using glucose oxidase is used as an example Potentiometer Biosensor Examples of Potentiometric Biosensor Penicillin biosensor Glucose biosensor Urea biosensor

Design Variables Immobilization Methods Change in Conformation adsorption (2) entrapment (3) covalent coupling (4) cross-linking Change in Conformation Change in Microenvironment Non-Uniform Distribution Reaction and Diffusion

Future Prospects Data Processing and Pattern Recognition Micro Instrument Molecular Electronics Multi-Disciplinary Nature

CONCLUSION Biosensors consist of bio-recognition systems, typically enzymes or binding proteins, such as antibodies, immobilized onto the surface of physico-chemical transducers Disadvantages They cannot be steam sterilized   They react with the product   And are oversensitive