Nanotechnology in Veterinary Sciences: Magnetic nanosystems development based in functionalized iron oxide with silica and gelatine as theranostic agents

Abstract

Magnetic nanoparticles (MNPs) based on magnetite (Fe3O4)
coated with silica find various applications in the field of biomedical
nanotechnology, due to their stability in aqueous medium.
However, the inertia of the silica in terms of its reactivity limits
the incorporation of specific functionalizers such as drugs and
other ligands of interest. The challenge of this work focuses on
obtaining biocompatible MNPs coated with silica and gelatin as
theranostic agents in various biomedical fields, including veterinary
medicine. Photodynamic therapy represents an alternative
and a complement to chemo and radiotherapy, conventional 

tools for the treatment of different pathologies such as oncology.
It consists of the use of photosensitive molecules that, when activated
with light of a certain wavelength, transfer their excess
of energy to neighboring oxygen molecules. This phenomenon
generates reactive oxygen species toxic to cells. Thus, the incorporation
of a photosensitive agent to the magnetic silica nanoparticles
functionalized with gelatin would facilitate their specific
transport to the affected cells from the effect of an external
magnetic field. This would result in a functional theranostic both
for the diagnosis (by MRI) and for the treatment (phototherapy).
In this work, various experimental conditions were explored
from MNPs of magnetite coated with citric acid and silica
for the deposition of gelatin from the co-precipitation method.
An optimum formulation was obtained that was characterized
integrally from the physicochemical point of view. As a photosensitive
molecule, methylene blue was selected and two routes
were explored for its incorporation into MNPs: 1-simple adsorption
for 24 hours and 2-encapsulation. The evaluation of both
procedures revealed the successful incorporation of the photosensitive
agent, obtaining magnetic nanosystems with potential
theranostic properties applicable in the veterinary field.