Agriculture Reference
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and chemical analysis. These procedures conventionally use techniques as titration,
spectrophotometry, electrophoresis, chromatography and others. These methods do
not enable a rapid, easy monitoring, because they are complex analytical methods
with expensive instrumentation, increasing the time of analysis, and also need well-
trained operators. Currently, food analysis needs affordable and rapid methods to
determine compounds that have not previously been monitored and to replace
existing ones (Wagner and Guilbault
1994
). An alternative to ease the analysis in
routine of industrial products is the biosensors development. Biosensors are a
subgroup of chemical sensors that integrate biological sensing elements with
physical transducers where the interactions between target molecules and biolog-
ical sensing elements are directly converted into an electronic signal (Viswanathan
and Radecki
2008
).
Applications of food nanotechnology might be defined under four parts. Systems
(releasing of bioactive compounds and nutraceuticals, food processing and improv-
ing functional products, detecting pathogens and improving food safety and devel-
oping packaging systems) might affect product quality and shelf life in a positive
way. In the last two groups, biosensors are playing an important role (Senturk
et al.
2013
).
8.2 Biosensors and Nanobiosensors
Biosensors are analytical devices combining a biological material, such as
enzymes, cells, antibodies, etc., a biologically derived surface associated with a
transducing system which can be piezoelectric, electrochemical, optical or mag-
netic. They have been applied to a wide range of analytical problems in food,
medicine and the environment (Schaertel and Firstenberg-Eden
1988
). A biosensor
is an instrument combining a recognition element with a transducing device.
Common to all such instruments is a support material, on which one of two
affinity-pairing partners—the recognition element—is immobilized. The partners
might be an antibody/antigen pair, an enzyme and its substrate, a receptor and its
specific ligand or even living cells and an analyte that binds specifically to them. To
detect the interaction of this pair, a biosensor uses a sensing transducer or device
that converts the biological response into an electrical signal that is stored, quan-
tified and amplified by a processor. There are many different kinds of biosensors
that could be classified according to the transducing system or the biological
recognition element used (Huet et al.
2010
).
According to another definition, biosensors show a conceptually novel approach
to on-site, real-time and simultaneous detection of multiple biohazardous agents.
Samples are minimally processed, and they present rapid testing in the field setting
with the option for post-analysis culture in the laboratory. Real-time detection of
pathogenic contaminants is critical to the control and prevention of widespread
damage from intentional or natural contamination. It offers immediate interactive
information about the sample being tested, allowing decision makers to take
