M. Pilar Calatayud

Determination of the blocking temperature of magnetic nanoparticles: The good, the bad, and the ugly

In a magnetization vs. temperature (M vs. T) experiment, the blocking region of a magnetic nanoparticle (MNP) assembly is the interval of T values were the system begins to respond to an applied magnetic field H when heating the sample from the lower reachable temperature. The location of this region is determined by the anisotropy energy barrier depending on the applied field H, the volume V, the magnetic anisotropy constant K of the MNPs and the observing time of the technique. In the general case of a polysized sample, a representative blocking temperature value

Magnetic Field-Assisted Gene Delivery: Achievements and Therapeutic Potential

T_B

Neuronal cells loaded with PEI-coated Fe3O4 nanoparticles for magnetically guided nerve regeneration

can be estimated from ZFC-FC experiments as a way to determine the effective anisotropy constant. In this work, a numerical solved Stoner-Wolfharth two level model with thermal agitation is used to simulate ZFC-FC curves of monosized and polysized samples and to determine the best method for obtaining a representative

The orientation of the neuronal growth process can be directed via magnetic nanoparticles under an applied magnetic field

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Magnetic nanoparticles as intraocular drug delivery system to target Retinal Pigmented Epithelium (RPE)

value of polysized samples. The results corroborate a technique based on the T derivative of the difference between ZFC and FC curves proposed by Micha et al(the good) and demonstrate its relation with two alternative methods: the ZFC maximum (the bad) and inflection point (the ugly). The derivative method is then applied to experimental data, obtaining the

Development and evaluation of 90Y-labeled albumin microspheres loaded with magnetite nanoparticles for possible applications in cancer therapy

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Relaxation time diagram for identifying heat generation mechanisms in magnetic fluid hyperthermia

distribution of a polysized

Magnetic Nanoparticles for Efficient Delivery of Growth Factors: Stimulation of Peripheral Nerve Regeneration

Fe_3O_4

In Silico before In Vivo: how to Predict the Heating Efficiency of Magnetic Nanoparticles within the Intracellular Space

MNP sample suspended in hexane with an excellent agreement with TEM characterization.

Ultrasmall Platinum Nanoparticles on Fe3O4: A Low-Temperature Catalyst for the Preferential Oxidation Reaction

The discovery in the early 2000s that magnetic nanoparticles (MNPs) complexed to nonviral or viral vectors can, in the presence of an external magnetic field, greatly enhance gene transfer into cells has raised much interest. This technique, called magnetofection, was initially developed mainly to improve gene transfer in cell cultures, a simpler and more easily controllable scenario than in vivo models. These studies provided evidence for some unique capabilities of magnetofection. Progressively, the interest in magnetofection expanded to its application in animal models and led to the association of this technique with another technology, magnetic drug targeting (MDT). This combination offers the possibility to develop more efficient and less invasive gene therapy strategies for a number of major pathologies like cancer, neurodegeneration and myocardial infarction. The goal of MDT is to concentrate MNPs functionalized with therapeutic drugs, in target areas of the body by means of properly focused external magnetic fields. The availability of stable, nontoxic MNP-gene vector complexes now offers the opportunity to develop magnetic gene targeting (MGT), a variant of MDT in which the gene coding for a therapeutic molecule, rather than the molecule itself, is delivered to a therapeutic target area in the body. This article will first outline the principle of magnetofection, subsequently describing the properties of the magnetic fields and MNPs used in this technique. Next, it will review the results achieved by magnetofection in cell cultures. Last, the potential of MGT for implementing minimally invasive gene therapy will be discussed.