This document discusses nanobiosensors, which are biosensors on the nano-scale size. It describes their two main components - a biological recognition element and a transducer. Various types are covered, including those using enzymes, antibodies, cells, nucleic acids, and nanoparticles. Applications discussed include medical uses like glucose monitoring, as well as environmental monitoring and agricultural quality control. The future potential of nanobiosensors for early cancer detection is also mentioned.

1. NANOBIOSENSORS
Biosensors on the nano-scale size

2. Nanobiosensor
A device incorporating a biological sensing element either
intimately connected to or integrated within a transducer and
a nanobiosensoris a biosensor that on the nano-scale size
• Recognition based on affinity between
complementary structures like:
enzyme-substrate, antibody-antigen , receptor-hormone
complex.
Selectivity and specificity depend on biological recognition
systems connected to a suitable transducer.

4. History
• The concept of biosensor was come up by Professor Leland
C Clark in 1956, who was identified as the father of the
biosensor concept.
• Oxygen electrode for measure the concentration of oxygen
in a any liquid
• 1962-the idea of oxygen electrode Clark came to reality

5. History ……….
• 1975- idea of utilizing bacteria as the biological element in
microbial electrodes for the measurement of alcohol
• 1975-first commercial biosensor (Yellow Spring
Instrumental Biosensor)
• 1975-first microbe based biosensor (first Immunosensor)
• 1983-first surface plasmonresonance (SPR) immunosensor
• 1987-Blood Glucose biosensor launchedby Medi-sense
ExacTech.
• 2000-nanotechnology biosensor, chip,quantumdots etc..

6. Two part of any biosensor

7. Component

10. Nucleic acids biosensor
• DNA biosensors are being developed as alternatives to
conventional DNA microarrays
• The complementary relationships between bases are used
for DNA sequence detection
• The reaction take place in the surface of the transducer

11. ANTIBODY/ANTIGEN:
• The high specificity between an antibody and an antigen can
be utilized in this type of sensor technology.
• Biosensors utilizing this specificity to detect the analyte

12. CELLS AND VIRUSES
• Microorganisms such as bacteria and fungi can be used as
biosensors to detect specific molecules or the overall
‘‘state’’ of the surrounding environment

13. ENZYMES
• Enzyme-based biosensors are composed of enzyme
bioreceptors that use their catalytic activity and binding
capabilities for specificity biomedical nanostructures
detection

14. Nanoparticle based biosensors
Acoustic wavebiosensor
Magnetic biosensor
Electrochemical biosensor

15. Acoustic wave biosensor
• The conjugation of antibody modified sol particles which bind
themselves on the electrode surface that has been complexed
with the particles of analyte conjugated in a manner that antibody
molecules are immobilized over the electrode surface.
• The large mass of bound sol particles of the antibody results in a
change in the vibrational frequency of the quartz based sensing
platform, and this change acts as the basis of detection.
• In general, the preferred diameter of the sol based antibody
particles is between 5 and 100 nm.
• Particles of gold, platinum, cadmium sulphide, and titanium
dioxide are generally preferred

17. Magnetic biosensor
• Utilize the specially designed magnetic nanoparticles.
• Mostly ferrite based materials, either used individually or in
combined form.
• Useful with reference to the biomedical applications
• With the incorporation of magnetic nanoparticles, the
conventionally used biodetection devices have further become
more sensitive and powerful.
• specific isolation of magnetically labeled targets with the help of
a magnetometer
• Special devices such as superconducting quantum interference
devices (SQUID)- for rapid detection of biological targets
• SQUID uses super paramagnetic nature of magnetic
nanoparticles.

19. Electrochemical biosensor
• To facilitate or analyze the biochemical reactions with the help of
improved electrical means.
• Mostly based on metallic nanoparticles.
• The chemical reactions between the biomolecules can be easily and
efficiently carried out with the help of metallic nanoparticles, which
significantly help in achieving immobilization of one of the reactants.
• This ability makes these reactions very specific and eliminates
undesirable side products.
• Example- 1) colloidal gold based nanoparticles have been used to
enhance the immobilization of DNA on gold electrodes which has
significantly increased the efficiency of an overall biosensor by
further lowering the detection limit.
• 2)Enzyme conjugated gold nanoparticles for the identification of
glucose, xanthine, and hydrogen peroxide

20. Nanotube based sensors
• Nanocarbons such as carbon powder, carbon nanotubes, graphene
sheets and carbon capsules
• Carbon nanotubes –hollow cylinder of a unique carbon sheet with a
single walled carbon nanotube (SWCNT) or concentric carbon sheets
of different diameters forming multiwalled carbon nanotubes
(MWCNT)
• CNT synthesis by arc-discharge, laser-ablation and chemical vapour
deposition
• cylindrical form of CNT- provides quantum confinement effect,
possibility to increase the chemical reactivity and electronic
properties of this particular carbon material
• high mechanical strength and folding abilities
• can enhance the electrochemical reactivity of important biomolecules

21. Con…….
• can promote the electron-transfer reactions of
proteins
• Accumulate important biomolecules (e.g.,nucleic
acids)
• Alleviate surface fouling effects
• Remarkable sensitivity of CNT- awide range of
electrochemical biosensors ranging from
amperometric enzyme electrodes to DNA
hybridization biosensors

23. Biosensor in medical field
Glucose biosensors
• In glucose biosensors, use of nanotubes as immobilizing
surfaces for enzyme glucose oxidaze
• Use of single walled nanotubes- for enzymatic detection
of glucose
• Increased performance- due to the high enzyme loading
and better electrical conductivities of nanotubes
• Most glucose biosensors are based on a GOD because
the GOD is able to identify glucose target molecules
quickly and accurately through catalyzing glucose to
gluconic acid and H2O2

24. Biosensor for determination of cholesterol
• Electrochemical biosensor for free cholesterol
monitoring
• Horseradish peroxidase and cholesterol oxidase are
simultaneously immobilized within a polymeric film,
• Which will react with cholesterol

25. DNA Electrochemical Biosensor for the
Detection of HIV
• The sensor relies on the immobilization and hybridization of
the 21- or 42-mer single-stranded oligonucleotide from the
HIV-1 U5 long terminal repeat (LTR) sequence at carbon
paste or strip electrode
• Hybridization between the complementary sequences is
determined by the enhancement of the chronopotentiometric
peak of the Co(phen)3
3+ indicator

26. Other example
• Electrochemical DNA biosensor for the detection
of TT and Hepatitis B virus
• Biosensor for avian influenza virus detection
• Silicon nanowire biosensor for highly sensitive
and rapid detection of Dengue virus

27. Biosensor assay for determination of haptoglobin
in bovine milk
• Mastitis is a disease which reduce the milk quality
• Haptoglobin is protein molecule present in the milk
• By introducing the antibody specific to the haptoglobin
• Developed SPR based biosensor

28. Multiplex biosensor immunoassays
for antibiotics
• Based on multi-component antibodies and/or combined
immunoassays in serially connected flow channels
• Development of multi-sulfonamide monoclonal antibodies
(Mabs)
• Which are immobilize in sensor surface
Example
Sulfonamides detection in Broiler’s blood serum

29. Screening of Chloramphenicol Residues in
Milk
• Chloramphenicol (CAP) are baned use for food
producing animals,
• polyclonal antibodies against CAP to immobilized
CAP on a sensor chip
• It is mainly spr based biosensor
• Which will give the specifity and concentration of
antibiotic

30. Analysis of b -Lactam Antibiotics
• monoclonal H1 antibody is injected across the sensor
surface
• It will bind on the transducer surface
• And it is mainly SPR based optical biosensor
• Analysis of b-lactum necessary due it will create problem
in fermentation process in milk

31. Application in agriculture
• Microbiological control in Foods
• Detection of infectious disease in products
• Quality control of marketable packaged
products
• Quality control of milk
• Quality control of fruits
• Quality control of meats

32. Applications of Nanobiosensors
• Biological Applications
• DNA Sensors; Genetic monitoring, disease
• Immunosensors; HIV, Hepatitis,other viral diseas, drug
testing, environmental monitoring…
• Cell-based Sensors; functional sensors, drug testing…
• Point-of-care sensors; blood, urine, electrolytes, gases,
steroids, drugs, hormones, proteins, other…
• Bacteria Sensors; (E-coli, streptococcus, other): food
industry, medicine, environmental, other.
• Enzyme sensors; diabetics, drug testing,

33. Environmental Applications
• Detection of environmental pollution and toxicity
• Agricultural monitoring
• Ground water screening
• Ocean monitoring

34. Future Application
Cancer Monitoring
• Nanobiosensors play a very important role for early cancer
detection in body fluids
• The sensor is coated with a cancer-specific antibody or
other bio recognition ligands. The capture of a cancer cell
or a target protein yields electrical, optical or mechanical
signal for detection