NanoLabels · Labelling of engineered nanomaterials for nanosafety tracing

Labelling of engineered nanomaterials for nanosafety tracing

There has been a notable rise in the development and production of engineered nanomaterials (ENMs) in recent years. However, concerns still remains regarding their potential impact on environmental safety and human health. Despite much research effort devoted to nanosafety studies in the past 15 years, a mechanistic understanding of the action of ENMs remains limited. A particular challenge is the detection of ENMs in complex biological tissues and environmental media, and against high natural background levels of either namoparticulate matter (natural borne nanoparticles) or constituent elements (e.g., Cu, Zn, or Fe). Besides, ENMs are highly dynamic, and prone to transformation (physical or chemical) upon entering the environment or biological tissues. For example, some metal-based NMs (silver, copper, zinc oxide) may dissolve quickly or transform to structurally and/or chemically different phases. These processes further complicate the detection of ENMs. A common solution for this problem involves the introduction of a tracer in the ENMs (“labelling”). A tracer maybe a fluorescence dye, a foreign element of low natural abundance, or a less-abundant isotope (stable or radioactive) of the same constituent element(s) of the ENM. Labeling with fluorescent dye or exogenous radioactive isotopes, however, possibly modify and change the surface chemistry of ENMs and thus alter their environmental and biological behavior. The labels may also detach from the core ENMs and would thus not replicate the real behavior of ENMs. Using radioisotope labelling is of more limited applicability due to the hazards involved in handling a radioactive substance. Compared with the labeling methods above, stable isotope labeling is safer and more versatile. The tracers may be detected using most commonly highly sensitive ICP-MS analysis (or other techniques that can distinguish isotopes of the same element, e.g. SIMS/nano-SIMS, thus providing very sensitive signals that could distinguish them from endogenous background elements in a variety of samples. Stable isotope labeling has no quenching issue of labels, thus is very suitable for life-cycle monitoring of various products and also conduct trophic transfer experiments. The objective of NanoLabels is to assign “ownership” or “source” to ENMs using different labelling techniques thereby enabling tracing of them in environment. The project not only helps scientific community to understand fundamental questions in nanosafety, i.e. the biological and environmental behaviour (uptake, translocation, transformation) by improving the tracing ability, but also provide labelling strategy that can be adopted by industry to facilitate applications such as nanosafety assessments before ENMs enter the market and environment, as well as for product authentication and tracking.

Data: CORDIS, © European Union