Bionsensors are devices that use biochemical reactions mediated by enzymes, tissues, or whole cells to detect chemical compounds through electrical, thermal, or optical signals. They work by having a bioreceptor interact with a specific analyte, and a transducer then measures this interaction and converts it into a proportional signal. There are several types of biosensors including calorimetric, potentiometric, amperometric, and optical biosensors that differ based on their transduction method. Biosensors have applications in food analysis, medical diagnosis, environmental monitoring, and more. Nanobiosensors integrate biosensing into miniaturized technologies like lab-on-a-chip devices for sensitive molecular diagnostics.

1. BIOSENORS

2. WHAT IS BIOSENSORS?
BIOSENSOR IS DEFINED AS A DEVICE THAT
USES SPECIFIC BIOCHEMICAL REACTIONS
MEDIATED BY ISOLATED
ENZYMES,IMMUNOSYSTEMS,TISSUES,ORGANELL
ES OR WHOLE CELLS TO DETECT CHEMICAL
COMPOUNDS USUALLY BY
ELECTRICAL,THERMAL OR OPTICAL SINGNALS.

3. WORKING PRINCIPAL
• Biosensors are operated based on the princpal of signal
transduction.
• Bioreceptor,is allowed to interact with a specific analyte.The
transducer measures this interaction and output is
proportional to the concentration of the analyte.The signal is
then amplified and processed by the electronic system.

4. TYPES OF BOSENSORS
1. Calorimetrc Biosensors
2. Potentiometric Biosensors
3. Acoustic Biosensors
4. Amperometric Biosensors
5. Optical Biosensors..
Based on transducter.
Based on bioreceptors
1. Enzyme biosensor
2. Microbial biosensor
3. Affinity biosensor.

5. 1. CALORIMETRIC BIOSENSORS
 Many enzyme catalysed reactions are
exothermic,generating heat which may be used as
a basis for measuring the rate of reaction and
,hence,the analyte concentration.
 An example is the use of glucose oxidase for
determination of glucose.
 The analyte solution is passed through a small
packed bed column contaning immobilized enzyme;
the temperature of the solution s determined just
before entry of the solution into the columm and just
leaving the column using separate thermistors.

6. 2.POTENTIOMETRIC BIOSENSORS
 These biosensors use ion-selective electrodes to
convert the biological reaction into electronic signal.
 Many reactions generate or ues H+ which is
detected and measured by the biosensor.urea
biosensor s an exmple of these biosensors.

7. 5.OPTICAL BIOENSORS
 These involv determining changes in light
absorption between the reactants and products of a
reaction,or measuring the light output by a
luminescent process.
 A most promisng biosensor involving luminescence
uses firefly enzyme luciferase for detection of
bacteria in food or clinical samples.

8. APPLICATIONS OF BOSENSORS
 Food analysis
 Drug development
 Crime detedcton
 Medical diagnosis
 Environmental
 Industrial process control
 Protein engineering
 Agriculture industry
 WesteWater treatment
 Manufacturing of pharmaceutical and replacement
of organs

9. NANOBIOSENSORS
 Advances in nanobiotecnology have led to the
development of nanoscale bioensors that have
exquisite sensitivity and versatility.
 They can be integrared into tecnologies such a lab-
on-a-chip to facilitator moleculer diagnostics.


10. BIOSENSORS IN MEDCAL FIELD
 Glucose bioensors are widely used in clinical applications for
diagnosis of diabetes mellitus
 A nobel biosensor,based on hafniu oxide(HfO2),has been used for
early stage detection of human interleukin.these are also used for
detedction of cardiovascular diseases.
 A new disease corona virus(covid 19) detection kit is repid test now
in all over world.Rapd testing takes just15 mins to provide result .