SIMS has become a valuable chemical analysis tool in biological research providing information on chemical distribution in cells and tissues at subcellular spatial resolution. SIMS is especially suitable for analysis of light elements such as Li, Be, B, and of the electrolytes important in cell metabolism. The high spacial resolution of FIB-SIMS using the V500 allows new areas such as the effects of nanoparticles/nanomaterials on biological systems to be studied.

User story: Biological effects of Ag nanoparticles and nanowires

Fizeşan et al used the V500 FIB-SIMS as part of a study to investigate the differences in biological effects on the a tetraculture representing the alveolar barrier of silver or coated silver nanomaterials. Two sizes of Ag nanoparticle (20 and 200 nm) and PVP coated silver nanowires with lengths up to 50 µm were studied. The high spacial resolution of the V500 allowed the researchers to study the morphology and composition of the nanostructures. Figure 1. shows SE and Ag SIMS images of the nanomaterials after sonification and deposition on a silicon substrate.

FIB-SIMS Ag Nanoparticle Biology Toxicology

Figure 1. modified from Fizeșan, I., Cambier, S., Moschini, E. et al. In vitro exposure of a 3D-tetraculture representative for the alveolar barrier at the air-liquid interface to silver particles and nanowires. Part Fibre Toxicol 16, 14 (2019). under creative commons license 4.0

The study evaluated oxidative stress induction, antioxidant defence mechanisms, pro-inflammatory responses and cellular death to investigate the biocompatibility of the silver nanomaterials. Significant cytotoxic effects were observed for all three types of silver nanomaterial at the highest tested doses. For example, all three types of silver nanomaterial increased the mRNA level of the anti-oxidant enzyme HMOX-1 and of the anti-oxidant metallothioneins. This research demonstrates that the direct exposure of a complex tetra-culture alveolar model to different types of silver nanomaterials induces shape- and size-specific biological responses. The researchers conclude that, of the three silver nanomaterials tested, silver nanowires were the most potent in inducing biological alterations.  At doses representative of an acute exposure in a high exposure occupational setting, silver nanowires induced prominent changes indicative of a pro-inflammatory response. The acute responses towards a dose representative for a full-lifetime exposure were also evaluated. However studies on chronic exposure scenarios at low dose are still required to establish the wider human health impact of silver nanomaterials. 

For more details, and to read the latest FIB-SIMS publications on biology, check out the V500 publications section here.