Université de Fribourg

A new angle on dynamic depolarized light scattering: number-averaged size distribution of nanoparticles in focus

Geers, Christoph ; Rodriguez-Lorenzo, Laura ; Urban, Dominic Andreas ; Kinnear, Calum ; Petri-Fink, Alke ; Balog, Sandor

In: Nanoscale, 2016, vol. 8, no. 34, p. 15813–15821

Size polydispersity is a common phenomenon that strongly influences the physicochemical properties of nanoparticles (NPs). We present an analytical approach that is universally applicable to characterizing optically anisotropic round NPs and determines directly the number-averaged size distribution and polydispersity via depolarized dynamic light scattering (DDLS). To demonstrate, we use...

Université de Fribourg

Plasmonic nanoparticles and their characterization in physiological fluids

Urban, Dominic A. ; Rodriguez-Lorenzo, Laura ; Balog, Sandor ; Kinnear, Calum ; Rothen-Rutishauser, Barbara ; Petri-Fink, Alke

In: Colloids and Surfaces B: Biointerfaces, 2016, vol. 137, p. 39–49

Nanoparticles possess unique properties beyond that of classical materials, and while these properties can be used for designing a dedicated functionality, they may also pose a problem to living organisms, to human health and the environment. The specific primary routes by which nanoparticles may interact with the human body include inhalation, injection, ingestion and application to the skin....

Université de Fribourg

Translocation of gold nanoparticles across the lung epithelial tissue barrier: Combining in vitro and in silico methods to substitute in vivo experiments

Bachler, Gerald ; Losert, Sabrina ; Umehara, Yuki ; Goetz, Natalie von ; Rodriguez-Lorenzo, Laura ; Petri-Fink, Alke ; Rothen-Rutishauser, Barbara ; Hungerbuehler, Konrad

In: Particle and Fibre Toxicology, 2015, vol. 12, no. 1, p. 18

The lung epithelial tissue barrier represents the main portal for entry of inhaled nanoparticles (NPs) into the systemic circulation. Thus great efforts are currently being made to determine adverse health effects associated with inhalation of NPs. However, to date very little is known about factors that determine the pulmonary translocation of NPs and their subsequent distribution to secondary...

Université de Fribourg

Nanoparticle colloidal stability in cell culture media and impact on cellular interactions

Moore, Thomas L. ; Rodriguez-Lorenzo, Laura ; Hirsch, Vera ; Balog, Sandor ; Urban, Dominic ; Jud, Corinne ; Rothen-Rutishauser, Barbara ; Lattuada, Marco ; Petri-Fink, Alke

In: Chemical Society Reviews, 2015, vol. 44, no. 17, p. 6287–6305

Nanomaterials are finding increasing use for biomedical applications such as imaging, diagnostics, and drug delivery. While it is well understood that nanoparticle (NP) physico-chemical properties can dictate biological responses and interactions, it has been difficult to outline a unifying framework to directly link NP properties to expected in vitro and in vivo outcomes. When introduced to...

Université de Fribourg

Uptake efficiency of surface modified gold nanoparticles does not correlate with functional changes and cytokine secretion in human dendritic cells in vitro

Fytianos, Kleanthis ; Rodriguez-Lorenzo, Laura ; Clift, Martin J.D. ; Blank, Fabian ; Vanhecke, Dimitri ; Garnier, Christophe von ; Petri-Fink, Alke ; Rothen-Rutishauser, Barbara

In: Nanomedicine: Nanotechnology, Biology and Medicine, 2015, vol. 11, no. 3, p. 633–644

Engineering nanoparticles (NPs) for immune modulation require a thorough understanding of their interaction(s) with cells. Gold NPs (AuNPs) were coated with polyethylene glycol (PEG), polyvinyl alcohol (PVA) or a mixture of both with either positive or negative surface charge to investigate uptake and cell response in monocyte-derived dendritic cells (MDDCs). Inductively coupled plasma optical...

Université de Fribourg

Nanoparticle polydispersity can strongly affect in vitro dose

Rodriguez-Lorenzo, Laura ; Rothen-Rutishauser, Barbara ; Petri-Fink, Alke ; Balog, Sandor

In: Particle & Particle Systems Characterization, 2015, vol. 32, no. 3, p. 321–333

When nanomaterials meet the biological world, the cellular interaction of nanoparticles is routinely assessed in in vitro systems. Establishing dose–response relationships requires that the dose of nanoparticles delivered to the cell is accurate and precise. Nanoparticles as such or coated with high molecular-weight compounds are rarely uniform and the influence of heterogeneity, including...

Université de Fribourg

Characterizing nanoparticles in complex biological media and physiological fluids with depolarized dynamic light scattering

Balog, Sandor ; Rodriguez-Lorenzo, Laura ; Monnier, Christophe A. ; Obiols-Rabas, Marc ; Rothen-Rutishauser, Barbara ; Schurtenberger, Peter ; Petri-Fink, Alke

In: Nanoscale, 2015, p. -

Light scattering is one of the few techniques available to adequately characterize suspended nanoparticles (NPs) in real time and in situ. However, when it comes to NPs in multicomponent and optically complex aqueous matrices – such as biological media and physiological fluids – light scattering suffers from lack of selectivity, as distinguishing the relevant optical signals from the...

Université de Fribourg

Dynamic depolarized light scattering of small round plasmonic nanoparticles: When imperfection is only perfect

Balog, Sandor ; Rodriguez-Lorenzo, Laura ; Monnier, Christophe A. ; Michen, Benjamin ; Obiols-Rabasa, Marc ; Casal-Dujat, Lucia ; Rothen-Rutishauser, Barbara ; Petri-Fink, Alke ; Schurtenberger, Peter

In: The Journal of Physical Chemistry C, 2014, vol. 118, no. 31, p. 17968–17974

Although small round gold nanoparticles (Au NPs) possess only a small degree of shape anisotropy, they support localized surface plasmon resonances and exhibit intrinsic optical anisotropy. These inherent features promote depolarized light scattering, whose temporal fluctuations carry information about rotational Brownian dynamics, and thus can be used to describe the size distribution of...

Université de Fribourg

In Vitro dosimetry of agglomerates

Hirsch, Vera ; Kinnear, Calum ; Rodriguez-Lorenzo, Laura ; Monnier, Christophe A. ; Rothen-Rutishauser, Barbara ; Balog, Sandor ; Petri-Fink, Alke

In: Nanoscale, 2014, p. -

Agglomeration of nanoparticles in biological fluids is a pervasive phenomenon that leads to difficulty in the interpretation of results from in vitro exposures, primarily due to the differing particokinetics of agglomerates to nanoparticles. Therefore, well-defined small agglomerates were designed that possessed different particokinetics profiles, and their cellular uptake was compared to a...

Université de Fribourg

Fluorescence-encoded gold nanoparticles: library design and modulation of cellular uptake into dendritic cells

Rodriguez-Lorenzo, Laura ; Fytianos, Kleanthis ; Blank, Fabian ; Garnier, Christophe von ; Rothen-Rutishauser, Barbara ; Petri-Fink, Alke

In: Small, 2014, vol. 10, no. 7, p. 1341–1350

In order to harness the unique properties of nanoparticles for novel clinical applications and to modulate their uptake into specific immune cells we designed a new library of homo- and hetero-functional fluorescence-encoded gold nanoparticles (Au-NPs) using different poly(vinyl alcohol) and poly(ethylene glycol)-based polymers for particle coating and stabilization. The encoded particles were...