Université de Fribourg

Simple and fast evaluation of relaxation parameters of magnetic nanoparticles

Lemal, Philipp ; Balog, Sandor ; Ackermann-Hirschi, Liliane ; Taladriz-Blanco, Patricia ; Hirt, Ann M. ; Rothen-Rutishauser, Barbara ; Lattuada, Marco ; Petri-Fink, Alke

In: Journal of Magnetism and Magnetic Materials, 2020, vol. 499, p. 166176

The efficacy of magnetic hyperthermia treatment depends on the optimal available magnetic nanoparticles (MNPs) that are excited in a given alternating magnetic field and viscosity of the region of interest. In this regard, assessing the relevant relaxation parameters is of upmost importance and could improve the speed of development of efficient applications. Here, we demonstrate how to...

Université de Fribourg

Polymer-coated gold nanospheres do not impair the innate immune function of human b lymphocytes in vitro

Hočevar, Sandra ; Milošević, Ana ; Rodriguez-Lorenzo, Laura ; Ackermann-Hirschi, Liliane ; Mottas, Ines ; Petri-Fink, Alke ; Rothen-Rutishauser, Barbara ; Bourquin, Carole ; Clift, Martin James David

In: ACS Nano, 2019, vol. 13, no. 6, p. 6790–6800

Gold nanoparticles (GNPs) are intended for use within a variety of biomedical applications due to their physicochemical properties. Although, in general, biocompatibility of GNPs with immune cells such as macrophages and dendritic cells is well established, the impact of GNPs on B lymphocyte immune function remains to be determined. Since B lymphocytes play an important role in health and...

Université de Fribourg

A hydrofluoric acid-free method to dissolve and quantify silica nanoparticles in aqueous and solid matrices

Bossert, David ; Urban, Dominic A. ; Maceroni, Mattia ; Ackermann-Hirschi, Liliane ; Haeni, Laetitia ; Yajan, Phattadon ; Spuch-Calvar, Miguel ; Rothen-Rutishauser, Barbara ; Rodriguez-Lorenzo, Laura ; Petri-Fink, Alke ; Schwab, Fabienne

In: Scientific Reports, 2019, vol. 9, no. 1, p. 7938

As the commercial use of synthetic amorphous silica nanomaterials (SiO2-NPs) increases, their effects on the environment and human health have still not been explored in detail. An often-insurmountable obstacle for SiO2-NP fate and hazard research is the challenging analytics of solid particulate silica species, which involves toxic and corrosive hydrofluoric acid (HF). We therefore developed...

Université de Fribourg

A quantitative study of particle size effects in the magnetorelaxometry of magnetic nanoparticles using atomic magnetometry

Dolgovskiy, Vladimir ; Lebedev, Victor ; Colombo, Simone ; Weis, Antoine ; Michen, Benjamin ; Ackermann-Hirschi, Liliane ; Petri-Fink, Alke

In: Journal of Magnetism and Magnetic Materials, 2015, vol. 379, p. 137–150

The discrimination of immobilised superparamagnetic iron oxide nanoparticles (SPIONs) against SPIONs in fluid environments via their magnetic relaxation behaviour is a powerful tool for bio-medical imaging. Here we demonstrate that a gradiometer of laser-pumped atomic magnetometers can be used to record accurate time series of the relaxing magnetic field produced by pre-polarised SPIONs. We have...