Highly Flexible Platform for Tuning Surface Properties of Silica Nanoparticles and Monitoring Their Biological Interaction

• Published in: ACS applied materials & interfaces Vol. 8; no. 7; pp. 4838 - 4850
• Main Authors: Ojea-Jiménez, Isaac, Urbán, Patricia, Barahona, Francisco, Pedroni, Matteo, Capomaccio, Robin, Ceccone, Giacomo, Kinsner-Ovaskainen, Agnieszka, Rossi, François, Gilliland, Douglas
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 24-02-2016
• Subjects: Cell Line; Cell Survival - drug effects; Culture Media - chemistry; Epithelial Cells - drug effects; Fluorescent Dyes - administration & dosage; Fluorescent Dyes - chemistry; Humans; Nanoparticles - administration & dosage; Nanoparticles - chemistry; Particle Size; Silicon Dioxide - administration & dosage; Silicon Dioxide - chemistry; Surface Properties; toxicity; A549 cells; uptake; silica nanoparticles; surface charge; fluorescent nanoparticles; epoxide functionalization; cell membrane interaction
• ISSN: 1944-8244; 1944-8252
• DOI: 10.1021/acsami.5b11216

The following work presents a simple, reliable and scalable seeding-growth methodology to prepare silica nanoparticles (SiO2 NPs) (20, 30, 50 and 80 nm) directly in aqueous phase, both as plain- as well as fluorescent-labeled silica. The amount of fluorescent label per particle remained constant regardless of size, which facilitates measurements in terms of number-based concentrations. SiO2 NPs in dispersion were functionalized with an epoxysilane, thus providing a flexible platform for the covalent linkage of wide variety of molecules under mild experimental conditions. This approach was validated with ethylenediamine, two different amino acids and three akylamines to generate a variety of surface modifications. Accurate characterization of particle size, size distributions, morphology and surface chemistry is provided, both for as-synthesized particles and after incubation in cell culture medium. The impact of physicochemical properties of SiO2 NPs was investigated with human alveolar basal epithelial cells (A549) such as the effect in cytotoxicity, cell internalization and membrane interaction.