13 Magnetic Nanoparticles for Life Sciences Applications
321
13.3.2 Fe 3 O 4 @SiO 2 Nanoparticle Toxicity on F. Oxysporum
Hyphal Cells
The experiments performed to outline the toxicity profile of the synthesized
Fe 3 O 4 @SiO 2 nanoparticles included colony growth assessment, the study of the
reactive oxygen species (ROS) accumulation and oxidative stress, and the study of
the fungal cell viability. In each case microconidia were grown in MM supplemented
with nanoparticle concentrations equal to 25, 50, 100 and 500 μg ml
−1 . The results
demonstrated the low toxicity of the nanoparticles to these forma specialis, even at
the highest nanoparticle concentration.
The experiments described above show that, although the fraction of Fe 3 O 4 @SiO 2
nanoparticles that penetrate the hypha is not very large, they remain as magnetic
aggregates adhered to the fungus surface, which is already enough to be separated
magnetically and to be detected by the magnetic reader of a biosensor. In addition, these nanoparticles in usual working doses are per se not toxic, so in principle
they are not harmful to other non-pathogenic/beneficial fungi that may exist in the
environment. This research constitutes the stage before the functionalization of the
nanoparticles for the detection of the pathogen and also paves the way for the search
of other biomolecules or active principles that could also be housed on the nanoparticle surface. This would result in multifunctional nanoparticles that could be used
not only for detection, but also for the selective control and eventual elimination of
the pathogenic fungus.
13.4 Summary and Persperctives
The work presented here evidences that magnetic nanoparticles are very attractive
nanomaterials to be considered in research related to Life Sciences areas different
from those more explored up to now, as the ones directly connected to Bio-medicine.
The results presented here show how these nanosystems can be very useful, first of
all, for basic research, to study the fundamental problems concerning their interaction
with plants and microorganisms. In addition, these studies open the way to solve a
large list of practical problems in agriculture, agronomy, environment, biotechnology,
food industry, etc., which in the short and/or long term also influence health, quality
of life and global welfare.
The work carried out with the Fe@C nanoparticles has shown that these nanoparticles are very appropriate for in-planta application and for plant cell research. First,
because they are suitable for the synthesis of different biocompatible magnetic fluids
easy to administer to living whole plants by different routes (injection, spray and
immersion of the roots in the fluid). Second, they have an adequate response to
magnetic field gradients. This characteristic, together with the high porosity and
high specific surface area of their coating makes them very appropriate as magnetically responsive carriers for the localized delivery of different chemical substances,
321
13.3.2 Fe 3 O 4 @SiO 2 Nanoparticle Toxicity on F. Oxysporum
Hyphal Cells
The experiments performed to outline the toxicity profile of the synthesized
Fe 3 O 4 @SiO 2 nanoparticles included colony growth assessment, the study of the
reactive oxygen species (ROS) accumulation and oxidative stress, and the study of
the fungal cell viability. In each case microconidia were grown in MM supplemented
with nanoparticle concentrations equal to 25, 50, 100 and 500 μg ml
−1 . The results
demonstrated the low toxicity of the nanoparticles to these forma specialis, even at
the highest nanoparticle concentration.
The experiments described above show that, although the fraction of Fe 3 O 4 @SiO 2
nanoparticles that penetrate the hypha is not very large, they remain as magnetic
aggregates adhered to the fungus surface, which is already enough to be separated
magnetically and to be detected by the magnetic reader of a biosensor. In addition, these nanoparticles in usual working doses are per se not toxic, so in principle
they are not harmful to other non-pathogenic/beneficial fungi that may exist in the
environment. This research constitutes the stage before the functionalization of the
nanoparticles for the detection of the pathogen and also paves the way for the search
of other biomolecules or active principles that could also be housed on the nanoparticle surface. This would result in multifunctional nanoparticles that could be used
not only for detection, but also for the selective control and eventual elimination of
the pathogenic fungus.
13.4 Summary and Persperctives
The work presented here evidences that magnetic nanoparticles are very attractive
nanomaterials to be considered in research related to Life Sciences areas different
from those more explored up to now, as the ones directly connected to Bio-medicine.
The results presented here show how these nanosystems can be very useful, first of
all, for basic research, to study the fundamental problems concerning their interaction
with plants and microorganisms. In addition, these studies open the way to solve a
large list of practical problems in agriculture, agronomy, environment, biotechnology,
food industry, etc., which in the short and/or long term also influence health, quality
of life and global welfare.
The work carried out with the Fe@C nanoparticles has shown that these nanoparticles are very appropriate for in-planta application and for plant cell research. First,
because they are suitable for the synthesis of different biocompatible magnetic fluids
easy to administer to living whole plants by different routes (injection, spray and
immersion of the roots in the fluid). Second, they have an adequate response to
magnetic field gradients. This characteristic, together with the high porosity and
high specific surface area of their coating makes them very appropriate as magnetically responsive carriers for the localized delivery of different chemical substances,