The document discusses a presentation on biosensors. It provides an overview of biosensors including their objectives, introduction, definition, basic principles, components, how they work, what constitutes an ideal biosensor, types of analytes and biosensors, advantages, and applications. It lists the group members presenting on biosensors and the topics they will cover such as the definition of a biosensor, its components, principles of operation, ideal characteristics, analytes, types of biosensors, advantages, and sensing techniques.

2. Presentation Topic
BIOSENSORS

3. Groupmates
Hassaan Ahmad (27)
Haseeba (28)
Sobia (29)
Rashid Minhas (30)
Eishma (31)
Sana khan (32)
Abbas khan (33)
Bushra Rehman (34)
Farooq Khalil (35)
Husna (36)

4. Objectives of today’s
Presentation
What is biosensor?
Components of Biosensor.
How does it work?
Ideal Biosensor.
Elements of biosensor.
Analyte.
Types of biosensor.
Advantages.
Applications.

5. Introduction
The word “sensor” find its origin from the Latin word “sentire”
which basically means ‘to identify’ anything.
By hearing this word sensor, the foremost thing that springs into
our minds is the concept of basic five human senses:
Ophthalmoception, Audioception, Gustaoception, Olfacception
and Tactioception.

6. Any device that has specific biochemical reactions to
detect chemical compounds in biological samples.
FATHER OF BIOSENSOR:
Professor Leland C Clark (1918-2005)

7. What is a biosensor?
It is an analytical device which converts a
biological response into an electrical signal.
It detects, records and transmits information
regarding a physiological change or process.
It determines the presence and concentration of a
specific substance in any test solution.

9. Schematic diagram showing the main components of a biosensor.
(a) The biocatalyst or bioelement converts the substrate to product.
(b) This reaction is determined by the transducer which converts it
to an electrical signal.
(c) Amplifier: The output from the transducer is amplified,
(d) processed and
(e) displayed.
a) Bioelement
b) Transducer
c) Amplifier
d) Processor
e) Display

10. Haseeba
Roll. No 28

11. Basic Principle of Biosensor
Basic principle of biosensor is explained in the
following three elements:
1. First biological recognition element which is highly
specific towards the biological material analytes
produces.
2. Second transducers detects and transduces signal
from biological target receptor molecule to electrical
signal which is due to reaction occur.
3. Third after transduction signal from biological to
electrical signal where its amplification is necessary
and takes place and read out in detector after
processing the values are displayed for monitor and
controlling the system.

13. Basic Principle
The biological material is immobaized and a contact is
made between the immobilized biological material and the
transducer.
The analyte binds to the biological material to form a bound
analyte which in turn produces the electronic response that
can be measured.
Sometimes the analyte is converted to a product which
could be associated with the release of heat, gas (Oxygen),
electrons or hydrogen ions. The transducer then converts
the product linked changes into electrical signals which can
be amplified and measured.

14. Sobia
Roll # 29

15. Components of Biosensor
1. Biological Element:
The component used to bind the target molecule.
It must be highly specific, stable under storage
conditions and immobilized.

16. 2. Physiochemical Transducer:
Acts as an interface, measuring the physical
change that occurs with the reaction at the
bioreceptor then transforming that energy into
measurable electrical output.

17. 3. Detector
Signals form the transducer are passed to a
microprocessor where they are amplified and
analyzed.
The data is then converted to concentration units
and transferred to a display or data storage device.

18. Rashid Minhas
Roll # 30

19. How does they work?
Biosensors basically involve the quantitative
analysis of various substances by converting their
biological actions into measurable signals.
Generally the performance of the biosensors is
mostly dependent on the specificity and sensitivity
of the biological reaction besides the stability of
enzyme.

21. Eishma
Roll # 31

22. How should be an Ideal Biosensor?
The output signal must be relevant to
measurement environment.
The functional surface must be compatible with
the transducer.
High specificity and selectivity (low
interference).
Sufficient sensitivity and resolution.
Sufficient accuracy and repeatability.
Sufficient speed of response and dynamic range.

25. Sana
Roll # 32

26. Analyte
‘A substance whose chemical constituents are
being identified and measured’.
What do you want to detect?
Molecule:
Protein, toxin, peptide, vitamin, sugar, metal ion.

27. Sample Handling
How to deliver the Analyte to the sensitive region?
Micro fluidics.
Concentration.
Filtration/Selection

28. Detection/Recognition
How do you specifically recognize the analyte?

29. Signaling
How will you come to know that there is a detection?
What are the common signaling Principles?
1. Optical (IR).
2. Electrical (conductivity).
3. Electromechanical (QCM).
4. Thermal.
5. Magnetic.
6. Pressure.

30. Abbas Khan
Roll # 33

31. Types of Biosensor
Enzyme Biosensors.
Immunosensors.
The DNA biosensors.
Magnetic Biosensors.
Thermal Biosensors.
Optical Biosensors.

32. Types of biosensors
Biosensors started in the 1960s by the pioneers Clark and
Lyons. Various types of biosensors being used are enzyme-
based, tissue-based, immuno-sensors, DNA biosensors, and
thermal and piezoelectric biosensors.
The first enzyme-based sensor was reported by Updike and
Hicks in 1967..

33. Enzyme biosensors
Enzyme biosensors have been devised on
immobilization methods, i.e. adsorption of enzymes by
van der Waals forces, ionic bonding or covalent
bonding. The commonly used enzymes for this purpose
are oxidoreductases, polyphenol oxidases, peroxidases,
and aminooxidases

34. Immunosensors were established on the fact that
antibodies have high affinity towards their respective
antigens, i.e. the antibodies specifically bind to pathogens or
toxins, or interact with components of the host's immune
system.
The DNA biosensors were devised on the property that
single-strand nucleic acid molecule is able to recognize and
bind to its complementary strand in a sample. The
interaction is due to the formation of stable hydrogen bonds
between the two nucleic acid strands.

35. Bushra
Roll # 34

36. Magnetic biosensors are miniaturized biosensors
detecting magnetic micro- and nanoparticles in microfluidic
channels using the magneto-resistance effect have great
potential in terms of sensitivity and size.
Thermal biosensors or calorimetric biosensors are
developed by assimilating biosensor materials as mentioned
before into a physical transducer.

37. Optical biosensors consist of a light source, as well as
numerous optical components to generate a light beam
with specific characteristics and to beeline this light to a
modulating agent, a modified sensing head along with a
photodetector.
The DNA biosensors were devised on the property that
single-strand nucleic acid molecule is able to recognize
and bind to its complementary strand in a sample. The
interaction is due to the formation of stable hydrogen
bonds between the two nucleic acid strands.

38. Farooq Khalil
Roll # 35

39. Advantages
Highly specific.
Independent of factors like stirring, pH etc.
Linear response, tiny and biocompatible.
Easy to use, durable.
Require only small sample volume.
Rapid.
Accurate.
Stable and sterilizable.

40. Typical Sensing Techniques
Fluorescence.
DNA Microarray.
SPR (Surface Plasma Resistance).
Impedence Spectroscopy.
QCM (Quartz Crystal Microbalance).

41. Husna
Roll # 36

42. Applications

43. curriculum development process in
Paksitan