Biosensors are analytical devices that combine a biological component with a physicochemical detector. They detect a biological response and convert it into a measurable signal. There are two main components - a biological recognition element like an enzyme or antibody and a transducer that converts the biological response into a detectable signal. Common types include amperometric, potentiometric, and optical biosensors which detect current, potential, or optical changes respectively. Biosensors have wide applications in healthcare, food safety testing, and environmental monitoring.

1. Rizwan Abbas Baho

2. 
 Definitions
 History
 Characteristics
 Components
 Principles
 Types
 Applications
Contents

3. 
Introduction

4.  Biosensors. are devices
which are used to sense
or detect the biological
activity.
 E.g. Glucometer
 A device that utilizes
biological
components e.g.
enzymes to indicate the
amount of a biomaterial
or processes.

5. 
 IUPAC definition
Biosensors are devices which use a biological
recognition element retained in direct spatial contact
with transduction system.
 Are devices use to sense or monitor the
reactions/processes.
 devices that convert a physical or biological event
into a measurable signal.
Biosensors

6. 
 Analytical device use for analysis reaction of
biochemical molecule .
 Detecting target analyte and converts a biological
response.
 Process the response and generate result.
(measureable signals)
Processing

7. Biosensor Schematic daigram

8. 
 The first 'true' biosensor was
developed by Leland C. Clark,
Jr in 1956 for oxygen detection.
 He is known as the 'father
of biosensors' and his
invention of the oxygen
electrode bears his name: 'Clark
electrode
History
Professor Leland C
Clark Jnr 1918–2005

9. 
 1916:
Immobilization of proteins: adsorption of invertase on
activated charcoal.
 1972:
First commercial biosensor: Yellow Springs Instruments
glucose biosensor.
 1980 :
First fiber optic pH sensor for in vivo blood gases.
 1987:
MediSense Launched blood glucose biosensor
Cont .

10. 
 High selectivity and sensitivity
 Reliability
 Short Assay time
 Stability
 Simplicity
 Low cost for operation and storage
Characteristics

11. 
 Industry -- process monitoring and control,
particularly food and drinks
 „Medicine -- diagnostics, metabolites,
hormones
 Military -- battlefield monitoring of poison
gases, nerve agents & people.
 „Domestic -- home monitoring of non acute
conditions
Why & Where

12. 
 Glucometer
 HCG test
 Benzene biosensor
 Nitrosamine biosensors
 Hydrogen peroxide biosensors
 DNA probe based biosensors
Examples

13.  Consist of two distinct components.
which include
 Biological component: enzyme, Cells etc.
 Physical component: transducer, amplifier etc.
Component of Biosensors

14. 

15. 
 Analyte (feed)
 Bioreception
 Transduction
 Display (Detection)
Process

16. 
 Biosensors works on basis of process/reaction
 Heat detection
 Distribution of charge
 Movement of electrons
 Light output
 Effects on mass
Principle

17. Detector

19. 
 Biosensors are categorized in five types according to
the principles follows,
 Calorimetric Biosensor
 Potentiometric Biosensor
 Amperometric Biosensor
 Optical Biosensor
 Piezo-electric Biosensor

20. 
 Calorimetric biosensors measure the temperature
change of the solution containing the analyte.
 Immobilized enzyme are used.
 Thermistors are used as detectors.
 Maintaining temperature is its disadvantage.
 Applied in case of exothermic process
Calorimetric biosensors

21. 
 These biosensors use ion-selective electrodes.
 Works where catalyze reaction generates Hydrogen
ions .
 Convert the biological reaction into electronic signal.
 Detected by pH meters
Potentiometric Biosensor

22. 
Potentiometric Biosensor

23. 
 Piezoelectric biosensors are based on the principle of
acoustics (sound vibrations), so also known as
acoustic biosensors.
 Piezo-electric devices use gold to detect the specific
angle at which electron waves are emitted .
 resonance frequencies which can be measured by
electronic devices.
Piezoelectric biosensors

24. 
 Functions on basis of
oscillations.
 Disadvantage in case of
crystals cease to
oscillate

25. 
 These electrodes function by the production of a
current .
 When potential is applied between two electrodes,
the magnitude of current being proportional to the
substrate concentration.
 Applicable in redox reactions.
Amperometric Biosensor

26. 
Amperometric Biosensor

27. 
 Optical biosensors are the devices that utilize the
principle of optical measurements.
 (absorbance, fluorescence, chemiluminescence etc.).
 Optical biosensors allow a safe non-electrical remote
sensing of materials.
Optical Biosensor

28. 
 Colorimetric
Color detection
 Photometric
light intensity
Examples
Electrochemical DNA
sensors

30. 
Applications

31. 
 Nutritional component
 Epidemiological research
 Nutritional fact
 Microbial Content
 Food Additives
Food Quality Analysis

32. 
 In the doctor's office as point of care devices. Like
glucose sensor.
 HCG strips for pregnancy tests.
 Diagnosis of diseases
 Cancer, microbial counts
Electrochemical (potentiometric and
amperometric)

33. 
 Electrochemical biosensors offer the capability of
detecting damage DNA as well as carcinogens that caused
the damage
 Environmental applications e.g. the detection of pesticides
and river water contaminants such as heavy metal ions.
 Determining levels of toxic substances before and after
bioremediation
 Detection of pathogens
Application

34. 
 Food quality control Hydrogen peroxide Biosensors
 Soft drinks (Benzene Biosensors)
 DNA probes
 Acetyl choline biosensors for soil analysis.
 Analysis of purification.
 Fermentation process and Microbial counts.
Down stream and
Biosensing

35. If any. Feel free to ask.