1. BTY100-Lec# 2.2
BIOSENSORS
Created By:
Soumya Srivastava

2. Outline
Biosensors: Basic Concept
WorkingPrinciple
Types
Examples

3. What are Biosensors???
SENSORS..???

4. SENSORS
A sensor is a converter that measures a physical quantity and converts it into a signal which can be read by an observer or by an (today mostly electronic) instrument.
Any Examples in your surrounding????
A piezoelectric sensor is a device that uses the piezoelectric effect, to measure changes in pressure, acceleration, strain or force by converting them to an electrical charge. The prefix piezo- is Greek for 'press' or 'squeeze'.
Ref: logos.co
Ref: en.clipart-fr.com
Ref:
Ref: javla.com
Button on Lift-Tactile Sensors
Touch Screen Mobile Phones
Peizo-electric sensor
Thermometer-Temperature Sensor

5. But Still......What are Biosensors???
BIOLOGY + SENSORS??

6. Professor Leland C Clark Jnr
Bio Sensors
A biosensor is an analytical device which converts a biological response into an electrical signal.
Any device that uses specific biochemical reactions to detect chemical compounds in biological samples.
Father of Biosensors:
EUREKA!!!
Ref:
Professor Leland C Clark Jnr
1918–2005

7. Characteristics of a Biosensor
Selectivity: Selectivity means that sensor detects a certain analyte and does not react with added mixtures and contaminants.
Precision: is the degree to which repeated measurements under unchanged conditions show the same results.
Signal stability : signal drift under constant conditions, which causes an error in measured concentration.
Sensitivity (detection limit): the minimal amount (or concentration) of analyte that can be detected.
Working range : range of analyte concentrations in which the sensor can operate.
Regeneration time : time required to return the sensor to working state after interaction with the sample.

8. Working Principle :
Ref: Biosensor Research Centre
Biosensors are based on the specific interactions between biological molecules.

9. Specific Interactions????
Enzyme and substrate
Antigen and Antibody
Dye and Ligand
Sugar and Lectin

10. Elements of a Biosensor
Ref:

11. A biosensor is a device composed of two main elements:
A bioreceptor that is an immobilized sensitive biological element (e.g. enzyme, DNA probe, antibody) recognizing the analyte (e.g. enzyme substrate, complementary DNA, antigen).
2. A transducer is used to convert (bio)chemical signal resulting from the interaction of the analyte with the bio-receptor into an electronic one.

12. 3.An Electronic Amplifier is an electronic device that increases the power of a signal. 4. A Data processing system is a combination of machines that for a set of inputs produces a defined set of outputs. The inputs and outputs are interpreted as data, facts, information, ... depending on the interpreter's relation to the system.

13. So overall the components collaborate in the following manner :
Quickyak:
Parts of a BIOSENSOR:
Bioreceptor
Transducer
Amplifier
Data Processing System

14. Working of Biosensor

15. Example of an enzyme based Biosensor
Blood Glucose Biosensor: It is very often used to measure the glucose concentration in blood.
Its applicable for diabetes patients for monitoring the blood glucose level.

16. Working:
The basic concept of the glucose biosensor is based on the fact that the immobilized GOx (Glucose oxidase-an enzyme) catalyzes the oxidation of β-D-glucose by molecular oxygen producing gluconic acid and hydrogen peroxide .
The enzyme is re-oxidized with an excess of a mediator .
The mediator is re-oxidized by a reaction at the electrode and a current is created.
The charge passing the electrode is proportional to glucose level.
Quickyak:
Examples of other biosensors may be given

17. Types of Biosensors
Biosensors are usually classified into various groups:
a) On the basis of type of transducer employed:

18. b) On the kind of bio recognition element utilized (antibody, enzymes, nucleic acids, and whole cells).
Enzyme Electrode
Enzymes
Enzymes are immobilised on the surface of an electrode
Current is generated when enzyme catalyses
Immunosensor
Antibodies
Detects change in mass when antibody binds to antigen
DNA Sensor
Use of DNA probe
Microbial Sensor
Microbial Cells

19. Applications The application of biosensor areas are following:
Clinical, diagnostics and medical applications.
Process control
Bioreactors
Quality control
Agriculture and veterinary medicine
Bacterial and viral diagnostics
Control of industrial waste water
Mining
Military defence industry.
Environmental control and monitoring

20. Advantages and Disadvantages
They can measure non-polar molecules that do not respond to most measurement devices.
Rapid and continuous control is possible with biosensors
Biosensors are specific due to the immobilized system used in them.
Response time is short (typically less than a minute) and Practical
Disadvantages
Heat sterilization is not possible because of denaturation of biological material.
Stability of biological material depends on the natural properties of the molecule that can be denatured under environmental conditions.
The cells in the biosensor can become intoxicated by other molecules that are capable of diffusing through the membrane.

21. Recent Advances Technologies Already Available in Market Zeo
Designed to analyze and improve sleep
In 2011, the widget maker Zeo introduced a mobile version to its Sleep Manager product line. By wearing a special headband, with sensors to measure electrical current, the Zeo could track different phases of sleep, such as Light, Deep and REM sleep, in addition to awake time. This data was then sent to an iPhone, iPod, or Android phone, and could be automatically uploaded to a personal and private online sleep database. This data along with some analytical tools could then be used to help improve your sleep and health.
Zeo tells you how you really sleep, and helps you find ways to improve your sleep
Accurately measure your sleep quality and sleep quanity at home
Discover factors that are stealing your Deep, REM & total sleep
Analyze your sleep patterns using online tools and journals
Add sleep coaching for a customized sleep improvement program tailored just for you

22. i-STAT Portable Clinical Analyzer
Handheld blood analyzer system
BODYBUGG
Personal calorie management system
Home Blood Glucose Monitors
ACCUTRANS
- Disposable blood pressure transducer

23. Future Endeavours Tattoo Biosensors: Quickyak:
Chip Sensors:
It allows one to measure pesticide content on food produce, water and soil.
Ring Sensor:
It allows one to continuously monitor heart rate and oxygen saturation. The device is shaped like a ring.
Smart Shirt:
This technology has been used to integrate sensors for monitoring the vital signs like temperature, heart rate and respiration rate.
Tattoo Biosensors:
Biosensor tattoos were developed to monitor sweat and lactate levels as indicators of excessive physical activity
Quickyak:
These products are still not commercialized

24. Ring Sensor Advantages Disadvantages
Wireless supervision of people during hazardous operations.
In an overcrowded emergency department.
Chronic surveillance of abnormal heart failure.
In cardio-vascular disease for monitoring the hyper tension.
Advantages
Continuous monitoring.
Easy to use.
Reducing hospitalization fee
Disadvantages
Initial cost is high.
Limited number of physiological parameters can be monitored.

25. Smart Shirts
Also known as GTWM i.e. Georgia Tech Wearable Motherboard.
This GTWM (smart shirt) provides an extremely versatile framework for the incorporation of sensing, monitoring and information processing devices.
It uses optical fibers to detect bullet wounds and special sensors and interconnects to monitor the body vital signs during combat conditions.
It is used to integrate sensors for monitoring the vital signs like temperature, heart rate and respiration rate.
Fig- Architechture of Smart Shirt[2]

26. Working of Smart Shirt (cont..)

27. A Day may come… Quickyak: Is this a biosensors
Soon humans may also have a unique bar code
Quickyak:
Is this a biosensors
Could they act as Biosensors??

28. Next Class: Nanobiotechnology