This ppt provides information about the biosensors and their types,method,working,components details.,

1. BIOSENSORS

2. What are biosensors?
A biosensor is an analytical device which converts a biological
signal into electrical signal.
An analytical device where immobilized layer of biological
material is in contact with sensor which analyses the
biological signal& convert it in to electrical signal
(Gronow,1984).

3.  According to a recently proposed IUPAC definition , “ A biosensor is a
self-contained integrated device which is capable of providing specific
quantitative or semi-quantitative analytical information using a biological
recognition element (biochemical receptor) which is in direct spatial
contact with a transducer element.

5. Dr. Leland Clark Jr
“Father of the biosensor”
History of Biosensors
First described in 1962 by Dr. Leland Clark
1969, a sensor was invented to detect urea
1972 ,the first glucose biosensor
commercialized by Yellow Springs Instruments

6. Components of the Biosensor
A) Biological components
1. Enzymes
2. Antibody
3. Microorganisms
4. Cell etc.
B) Physical components
1. Transducer
2. Detector
3. Signal processing unit
4. Amplifier

7. Schematic illustration of a Biosensor
signal prossing monitoramplificationtransducerbioreceptor

8. Working of a Biosensor
Detector

9. Methods of detection
1. Electrochemical method of detection-
Production of electrical potential due to change distribution of
the electrons.
2. Amperometric method of detection-
Movement of electrons due to redox reactions.
3. Thermistor method of detection-
Heat released or absorbed by the reactions.
4. Optical method of detection-
Light produced or absorbed by the reaction.
5. Piezoelectric method of detection-
Change in the mass of biological components as a result of the
reaction.

12. 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.

13. Potentiometric Biosensor
• For voltage: Change in distribution of charge is detected using ion-
selective electrodes, such as pH-meters.

14. 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.

15. Advantages:
Rapid detection
Small volumes of samples needed
Can be used by the patient (blood glucose monitor)
They can measure nonpolar molecules that do not respond to most measurement devices
Biosensors are specific due to the immobilized system used in them
Rapid and continuous control is possible with biosensors
Response time is short (typically less than a minute) and
Practical

16. Disadvantages;
Cost
May require expertise to use
Sample collection can be painful
Stability of biological material (such as enzyme, cell, antibody, tissue, etc.),
depends on the natural properties of the molecule that can be denaturalized
under environmental conditions (pH, temperature or ions)
 The cells in the biosensor can become intoxicated by other molecules that
are capable of diffusing through the membrane.

17. Common biosensors
Blood glucose monitors
Heart and blood pressure monitors
Pacemakers
HIV and pregnancy tests

18. Blood glucose monitors
Used by diabetics to measure blood glucose concentration
Helps patients determine their insulin dose
Uses electrochemistry for detection

19. Pregnancy test
Detects the hCG protein in urine.
.

20. Wearable Biosensors
Ring Sensor
Smart Shirt

21.  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
 In military applications(gases used in chemical
Application of Biosensor

22. Application in agriculture and food products
Biosensor in agriculture

23. Biosensors can be used to measure the levels of pesticides, herbicide and
heavy metals in the soil and ground water.
 Biosensors can also be used to forecast the possible occurrence of soil
disease, which has not been feasible with the existing technology.
• A biosensor has been developed for the detection of the fungus
Phakopsora pachyrhizi that causes Asian rust or Soybean rust.
• Biosensor for the detection of aflatoxin in olive oil has been developed

24. Biosensors in today’s world;
• Mostly they are tested only on non-real samples such as in distilled
water or buffer solutions, but few applied to real samples in recent
years.
• The application of biosensors to real samples must be a necessary step
before their commercialization, which is the aim of the device
development.
• Most commercial biosensors developed are needed to focus in clinical
applications, such as for glucose and lactate.
• Prospective biosensor market for food, pharmaceutical, agriculture,
military, veterinary and environment are still to be explored.

25. Requirements needed for successful commercialization of biosensors
Insensitive
to
temperatur
e
Insensitive to
environmental
interference
The accuracy
and
reproducibility
The
response
rate
Costs and
capital
Biosensor
Prevention of
pollution

26. Reference;
• ‘Research and development in biosensors’ by F.W. Scheller, U.
Wollenberger, A. Warsinke
• Biosensors by Ralph P. Cavalieri and Jose I. Reyes De Corcuera
• Research paper on‘ Biosensor; use in agriculture’in International
journal of scientific research.