This document provides an overview of enzyme-based biosensors. It discusses the history and components of biosensors, including the biological recognition element and transducer. Common types of biosensors are described based on their method of detection such as calorimetric, optical, and potentiometric. Examples like glucose meters and pregnancy tests are explained. Glucose meters work by measuring the hydrogen peroxide produced from the reaction of glucose and glucose oxidase using an electrode. Overall, the document provides a high-level introduction to the principles, components, applications and examples of enzyme-based biosensors.

1. Topic : ENZYME BASED BIOSENSOR
Submitted to: Submitted by:
Ms Kanushri Ranawat Shivangi Soni

2. Index
• History
• Introduction
• Sensor
• Principle
• Components and working
• Enzymes biosensor
• Glucometer
• Types of biosensor
• Advantage and disadvantage
• Reference

3. History
First commercial glucose biosensor was invented in 1975.

4. Introduction
It is an analytical device, used for the detection of analyt, that
combine a biological component
with a physiochemical detector.

5. Sensor
- It is an analytical device which convert a biological response into an electric
signal.
- It detects, records and transmit information regarding a physiological change or
process.

6. Principle
 1. Biological recognization
element which is highly specific
toward the biological analyt.
2. Transducer detect and traduce
signal from biological target to
electric signal which is due to
reaction occur.
3. This electrical signal are
amplified and can be read in
detector after processing the
value are display in monitor.

7. Components and Working
Bioreceptor (biological)+Transducer (physiological)

8. Components:
Bioreceptor
(biological)
1.The component used to bind
the target molecule.
2. This must be highly
specific, stable under storage
condition.
3. And immobilized on
transducer.

9. Immobilization of receptor
The bioreceptor must immobilized on transducer by following
method.
- physical adsorption
- covalent binding
-entrapment etc.

10. Transducer
- It convert the bio recognization eventinto a measurable
signal.
- This is done by measuring the change that occur in the
bioreceptor reaction.

11. Detector
- Signal from the transducer are passed to a
microprocessor where they are amplified and analyze.
- The data is then converted and is display on monitor.

12. Ideal biosensor should be:
- highly specific for analyt.
- device should be tiny and biocompatible.
- device should be cheap and small.
- easy to use.
- should be durable.
- capable of repeated use.
- Should be sterilizable.
- Should require small sample volume.

13. Enzyme based biosensor
- The biological material i.e. Enzyme is immobilized on transducer.
- The analyte i.e. substrate binds to the enzyme to form a bound analyte.
- The analyte is converted into a product which could be associated with the
release of heat, gas, or hydrogen ions.
- The transducer then convert the product linked change into electrical single
which is amplified and measure.

14. Example of enzyme biosensor
Glucometer

15. Procedure
- A blood glucose meter is an electronic device for measuring the blood
glucose level.
- A relatively small drop of blood is placed on a disposable test strip
which interfaces with a digital meter.
- Within seconds, the level of blood glucose will be shown on the digital
display.

16. How does it works?
- Glucose react with glucose oxidase (GOD) to form gluconic acid.
- Glucose mediator reacts with surrounding oxygen to form H2O2
(hydrogen peroxide).
- higher the glucose content higher the O2 consumption.
- glucose content can be detect by electrode.

17. 3 different type of transducer can be use:
- an oxygen sensor that measure 02 concentration.
- A pH sensor that measure the gluconic acid production.
- A peroxide sensor that measure H2O2 concentration.

19. Types of biosensor
1. Calorimetric: measure changes in heat.
2. Optical: measure changes in light intensity.
3. Electrometric: detect changes in electrical conductivity.
4. piezoelectric: measure changes in mass.
5. potentiometric: measure changes in charge.

20. calorimetric biosensor
- these biosensor are also called thermometric biosensor or
thermal biosensor.
- Many enzyme catalyzed reaction produce heat (exothermic)
- calorimetric biosensor measure the change in temperature of
the solution containing the analyt.

21. Optical biosensor
- this biosensor measure the changes in fluorescence or in
absorbance caused by the product generated by catalytic reaction.
Luciferin + ATP + O2 ---- oxyluciferin +CO2 + pyrophosphate + light
the above reaction happens in presence of enzyme Luciferase.

22. Potentiometric biosensor
- These biosensor use ion selective electrode to convert the
biological reaction into electronic signal.
- The electrodes employed are most commonly pH meter glass
electrodes.
CO(NH2)2 + 2H2O + H(+ion) -- 2NH4 (+ion) + HCO3 (-ion)
The above reaction happens in presence of enzyme urease.

23. Advantage
1. more specific than cell based sensor.
2. Faster responds due to shorter diffusion path (no cell walls).
Disadvantage
1. More expensive to produce due to additional problem of isolating the enzyme.
2. Enzyme are often unstable when isolated.

24. Example

25. Example

26. Example
pregnancy test kit

27. Reference
• B.D. Singh, Biotechnology ,Expanding Horizon .
Second edition, Chapter 15 , Enzymes Technology ,
Biosensor , Page 666-672.
• http://www.slideshare.net/951384/biosensors-
33317356
• http://engineering.mit.edu/ask/how-do-glucometers-
work
• https://en.wikipedia.org/wiki/Blood_glucose_monitoring
#Blood_glucose_meters
• http://de.123rf.com/photo_9176220_diabetes-
patienten-lustig-finger-glucose-level-bluttest-von-
neuen-smart-glucometer-auf-weissem-hinte.html

28. THANK YOU