JRC scientists, in collaboration with the EU FP7 funded project NanoMile, developed a flexible method to prepare size controlled and surface modified nanoparticles for use in systematic nanotoxicity studies. This tool can be used by cell biologists attempting to unravel the complexities of how biological systems interact with nanomaterials.
When nanoparticles encounter living systems their surface chemistry is an important factor in defining the way that the biological systems react towards them. Such reactions, whether beneficial or harmful, can be crucial in determining whether a nanomaterial is effective in its desired application, such as in the case of a nanomedicine, or problematic by interfering with an organism following unintentional exposure. Recent studies have begun to systematically examine the effect of particle surface chemistry on in-vitro cell systems but progress has been limited due to the complexity of producing an adequate variety of chemically modified nanomaterials to use as models in the testing. Such libraries, generally based on gold nanoparticles, are challenging to produce as the desired chemical variations use tailored thiol molecules which, in many cases, must be laboriously custom synthesised as they are not commercially available.
In a study undertaken by JRC in collaboration with the FP7 project NanoMile, an alternative method has been developed which offers a simple, yet reliable and scalable seed-growth methodology to prepare libraries of size controlled, surface modified silica nanoparticles suited to studies of nano-bio-interactions. In this work, mono-dispersed silica particles synthesised by a simple, aqueous seed-growth method are coated with a thin, chemically reactive layer which can, in a second step, bind a wide variety of different amino functionalised molecules whose nature then defines the surface chemistry of the particles. Since the binding step proceeds under mild aqueous conditions and many different amino functionalised molecules are available commercially this procedure offers a flexible way to produce libraries of model nanoparticles with a combination of varied chemistry and controlled size. This approach to modifying surface chemistry has been verified by binding different amino acids to change surface charge while alkylamino compounds of varying length can be used to change particle hydrophobicity.
Read more in:I. Ojea-Jiménez et al. "Highly flexible platform for tuning surface properties of silica nanoparticles and monitoring their biological interaction", ACS Applied Material Interfaces, 8 (2016) 4838–4850, doi:10.1021/acsami.5b11216
- Publication date
- 9 May 2017