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C. Marquina
such as those used in phytosanitary treatments, for pest control, etc. Although there
are still many problems to be solved for their large-scale use, the work presented here
can help in preliminary studies at laboratory scale (for instance, in those necessary for
the optimization of the routes and doses to be administered in a specific treatment).
Regarding their use in the laboratory, the Fe@C nanoparticles have been found as
very convenient when working with plants and plant cells, as they are very easy to be
visualized (without the need of any extra marker) by the microscopy techniques and
protocols that have been developed during the execution of the different experiments.
Therefore, the Fe@C magnetic nanoparticles can be of great help in elucidating the
penetration mechanisms and the localization of the nanoparticles into the cell (for
instance, by HR-TEM experiments) as well as the cell response to the nanocarriers.
These topics are currently under discussion and are of great importance from the
point of view of both basic and applied research (for example for the case of genetic
engineering). Moreover, cell viability and cytotoxicity assays as well as the study of
the relationship between cytotoxicity and phytotoxicity are of paramount importance
prior their use in practice.
The use of magnetic nanoparticles coated with silica is much more exploited
than that of the other magnetic nanoparticles. Their widespread implementation in
biomedical applications has stimulated the rapid growth that their utilization in areas
such as biotechnology, agriculture and agronomy is currently experiencing. The
previous section summarizes what constitutes a systematic study of the interaction
of Fe 3 O 4 @SiO 2 nanoparticles with a fungus that in one of its forma specialis is
a plant pathogen and even an opportunistic human pathogen. One aspect that this
work has highlighted is the importance of the physicochemical properties of the
nanoparticles that have to be precisely tuned for each particular application. In this
particular case, the size of the nanoparticles and their electrical charge has been
determinant for their application in a biosensor that detects and allows the separation of the pathogenic fungus from infected soils, plants and crops. In particular,
the different sign of the charge of the fungal cell wall of these hyphal cells and that
of the silica coating causes the nanoparticles to be located in the form of relatively
large magnetic aggregates on the fungal hypha. This has turned out to be decisive
for the development of the future device, facilitating the detection and subsequent
magnetic separation of the pathogen. Therefore, in the same way as for a given cell
model it is necessary to know the toxicity profile of a particular nanomaterial, an
exhaustive characterization of the physicochemical properties of this nanomaterial is
also essential. At present, nanotechnology offers us advanced characterization techniques (which include magnetic characterization techniques, advanced microscopy,
different spectroscopies etc.) that are more and more intended for the characterization of materials of biological interest, as well as biomaterials. In addition, the
methodology and protocols developed for the case of the silica coated nanoparticles
interacting with Fusarium oxisporum might then be implemented in the detection
and control of other pathogens and pests, which would have a major impact on areas
such as agronomy and agriculture, food industry etc. Moreover, this study could be
extended to other fungi that are or can become pathogenic for humans, as for example
those of Candida genus. Just as the resistance to antibiotics developed by bacteria
C. Marquina
such as those used in phytosanitary treatments, for pest control, etc. Although there
are still many problems to be solved for their large-scale use, the work presented here
can help in preliminary studies at laboratory scale (for instance, in those necessary for
the optimization of the routes and doses to be administered in a specific treatment).
Regarding their use in the laboratory, the Fe@C nanoparticles have been found as
very convenient when working with plants and plant cells, as they are very easy to be
visualized (without the need of any extra marker) by the microscopy techniques and
protocols that have been developed during the execution of the different experiments.
Therefore, the Fe@C magnetic nanoparticles can be of great help in elucidating the
penetration mechanisms and the localization of the nanoparticles into the cell (for
instance, by HR-TEM experiments) as well as the cell response to the nanocarriers.
These topics are currently under discussion and are of great importance from the
point of view of both basic and applied research (for example for the case of genetic
engineering). Moreover, cell viability and cytotoxicity assays as well as the study of
the relationship between cytotoxicity and phytotoxicity are of paramount importance
prior their use in practice.
The use of magnetic nanoparticles coated with silica is much more exploited
than that of the other magnetic nanoparticles. Their widespread implementation in
biomedical applications has stimulated the rapid growth that their utilization in areas
such as biotechnology, agriculture and agronomy is currently experiencing. The
previous section summarizes what constitutes a systematic study of the interaction
of Fe 3 O 4 @SiO 2 nanoparticles with a fungus that in one of its forma specialis is
a plant pathogen and even an opportunistic human pathogen. One aspect that this
work has highlighted is the importance of the physicochemical properties of the
nanoparticles that have to be precisely tuned for each particular application. In this
particular case, the size of the nanoparticles and their electrical charge has been
determinant for their application in a biosensor that detects and allows the separation of the pathogenic fungus from infected soils, plants and crops. In particular,
the different sign of the charge of the fungal cell wall of these hyphal cells and that
of the silica coating causes the nanoparticles to be located in the form of relatively
large magnetic aggregates on the fungal hypha. This has turned out to be decisive
for the development of the future device, facilitating the detection and subsequent
magnetic separation of the pathogen. Therefore, in the same way as for a given cell
model it is necessary to know the toxicity profile of a particular nanomaterial, an
exhaustive characterization of the physicochemical properties of this nanomaterial is
also essential. At present, nanotechnology offers us advanced characterization techniques (which include magnetic characterization techniques, advanced microscopy,
different spectroscopies etc.) that are more and more intended for the characterization of materials of biological interest, as well as biomaterials. In addition, the
methodology and protocols developed for the case of the silica coated nanoparticles
interacting with Fusarium oxisporum might then be implemented in the detection
and control of other pathogens and pests, which would have a major impact on areas
such as agronomy and agriculture, food industry etc. Moreover, this study could be
extended to other fungi that are or can become pathogenic for humans, as for example
those of Candida genus. Just as the resistance to antibiotics developed by bacteria