Structural and magnetic properties of nanoparticles of NiCuZn ferrite prepared by the self-combustion method

NiCuZn ferrites were prepared by the sol-gel self-combustion method. Nanosized, homogeneous and highly reactive powders were obtained at relatively low temperatures. In present work the variations of structural, magnetic, and microwave properties of NiCuZn ferrite nanoparticles were studied as a function of the annealing temperature. The analysis of XRD patterns showed that only the spinel phase is present. Cell parameters slightly vary with thermal treatment while a crystalline size increases. Magnetic nanoparticles were mixed with an epoxy resin for reflectivity studies with a microwave vector network analyzer using the microwave-guide method in the range of 7.5 to 13.5GHz. Static saturation magnetization value (measured by SQUID) and microwave absorption show clear dependence on the annealing temperature/particle size and the absorption maximum moves towards the higher frequencies with an increase in the average size of the particles

Estudio de la morfología de partículas de magnetita y carbón activado

El arsénico representa un peligro para la salud pública ya que la intoxicación prolongada mediante el consumo de las aguas subterráneas contaminadas acarrea problemas tales como cáncer de piel y lesiones cutáneas. Por estas razones, es necesario encontrar métodos para la remediación que sean económicos y accesibles. En este trabajo, se diseñó un material adsorbente desarrollado a partir de residuos naturales. Se prepararon muestras de carbón activado dopado con magnetita debido a su elevada capacidad para adsorber arsénico. Se eligió el uso de cáscara de maní como precursor para la producción del carbón activado ya que es un residuo muy común procedente de la industria agropecuaria Argentina. Se estudió el proceso de síntesis de las partículas de magnetita sobre el carbón activado en función del tiempo de reacción. Se observó que luego de 6 horas de reacción se genera una dispersión de las partículas de magnetita provocando que no se generen “cúmulos”. Mediante la técnica empleada se logró controlar el tamaño de partícula soportada en la matriz carbonosa.Fil: Pellegrini, J. y de Celis, Jorge Pablo. Facultad Regional Avellaneda, UTN. (Departamento de Ingeniería Química) Argentina,Fil: APHESTEGUY, J. LAFMACEL, Facultad de Ingeniería. UBA. ArgentinaPeer Reviewe

Magnetic carbon nanostructures and study of their transport in microfluidic devices for hyperthermia

Cancer incidence and mortality are growing worldwide at an alarming pace, emphasizing the urgent need for new strategies to combat this disease. One of the frontiers of cancer research is currently focused on the design of multifunctional magnetic nanoparticles capable to achieve the synergistic cancer theranostics (both diagnosis and therapy). Although the potentiality that these multifunctional nanosystems represents to nanomedicine, cancer treatment and diagnostic, there are still many challenges that must be addressed in a near future before this approach became a reality. The development of efficient multifunctional magnetic nanosystems able to selectively destroy cancer cells in detriment of healthy ones, is one of the main challenges that have damped the spread of this technology into clinical applications. The limited biological and biophysical studies between the biomedical nanosystems and cells/tissues/organs is another challenge that has to be addressed. With these two main challenges in mind, the present Ph.D. work was focused in the development of: (1) Multifunctional magnetic carbon nanostructures as multifunctional nanosystems for the treatment of cancer, and (2) New advanced microfluidic devices capable to give new insights over the developed nanosystems and human cells.The successful accomplishment of the multidisciplinary tasks considered in this Ph.D. work, was supported by important collaborations that were strengthened at different stages in the frame of this Ph.D. project, namely INL -International Iberian Nanotechnology Laboratory (Braga, Portugal); CeRiCol -Centro Ricerche Colorobbia Consulting (Vinci, Italy); CIMO -Centro de Investigacao da Montanha (Braganca, Portugal) and Harvard-MIT Division of Health Sciences and Technology (Cambridge, USA).R.O. Rodrigues acknowledge the Ph.D. scholarship SFRH/BD/97658/2013 granted by Fundacao para a Ciencia e a Tecnologia (FCT), as well as a Fulbright Research Grant 2017, granted by Fulbright Portugal