Person:
Garayo Urabayen, Eneko

Profile Picture

Email Address

Birth Date

Research Projects

Organizational Units

Job Title

Last Name

Garayo Urabayen

First Name

Eneko

person.page.departamento

Física

ORCID

0000-0002-3144-7898

person.page.upna

811381

Name

Filters

2019 - 201912020 - 20211
Reset filters

Settings

Author: García, José Ángel × Subject: Magnetic hyperthermia ×

Search Results

Now showing 1 - 2 of 2
  • Thumbnail Image
    PublicationOpen Access
    Iron oxide nanorings and nanotubes for magnetic hyperthermia: the problem of intraparticle interactions
    (MDPI, 2021) Das, Raja; Alonso Masa, Javier; Kalappattil, Vijaysankar; Nemati, Zohreh; Rodrigo, Irati; Garayo Urabayen, Eneko; García, José Ángel; Manh-Huong, Phan; Srikanth, Hariharan; Ciencias; Zientziak
    Magnetic interactions can play an important role in the heating efficiency of magnetic nanoparticles. Although most of the time interparticle magnetic interactions are a dominant source, in specific cases such as multigranular nanostructures intraparticle interactions are also relevant and their effect is significant. In this work, we have prepared two different multigranular magnetic nanostructures of iron oxide, nanorings (NRs) and nanotubes (NTs), with a similar thickness but different lengths (55 nm for NRs and 470 nm for NTs). In this way, we find that the NTs present stronger intraparticle interactions than the NRs. Magnetometry and transverse susceptibility measurements show that the NTs possess a higher effective anisotropy and saturation magnetization. Despite this, the AC hysteresis loops obtained for the NRs (0-400 Oe, 300 kHz) are more squared, therefore giving rise to a higher heating efficiency (maximum specific absorption rate, SAR(max) = 110 W/g for the NRs and 80 W/g for the NTs at 400 Oe and 300 kHz). These results indicate that the weaker intraparticle interactions in the case of the NRs are in favor of magnetic hyperthermia in comparison with the NTs.
  • Thumbnail Image
    PublicationOpen Access
    Unlocking the potential of magnetotactic bacteria as magnetic hyperthermia agents
    (Wiley, 2019) Gandía, David; Gandarias, Lucía; Rodrigo, Irati; Robles García, Joshua; Das, Raja; Garayo Urabayen, Eneko; García, José Ángel; Ciencias; Zientziak
    Magnetotactic bacteria are aquatic microorganisms that internally biomineralize chains of magnetic nanoparticles (called magnetosomes) and use them as a compass. Here it is shown that magnetotactic bacteria of the strain Magnetospirillum gryphiswaldense present high potential as magnetic hyperthermia agents for cancer treatment. Their heating efficiency or specific absorption rate is determined using both calorimetric and AC magnetometry methods at different magnetic field amplitudes and frequencies. In addition, the effect of the alignment of the bacteria in the direction of the field during the hyperthermia experiments is also investigated. The experimental results demonstrate that the biological structure of the magnetosome chain of magnetotactic bacteria is perfect to enhance the hyperthermia efficiency. Furthermore, fluorescence and electron microscopy images show that these bacteria can be internalized by human lung carcinoma cells A549, and cytotoxicity studies reveal that they do not affect the viability or growth of the cancer cells. A preliminary in vitro hyperthermia study, working on clinical conditions, reveals that cancer cell proliferation is strongly affected by the hyperthermia treatment, making these bacteria promising candidates for biomedical applications.