Volume 94, Issue 10

Superparamagnetic Iron Oxide Nanoparticles (SPIONs) are more and more used in biomedical applications such as therapy (treatment for certain cancers, hyperthermia), diagnostic (contrast agent for Magnetic Resonance Imaging) or both. For these applications, SPIONs must be stable in an aqueous solution, monodisperse, with a narrow size distribution and without aggregation. To obtain these nanoparticles, a microwave process is carried out in this study as an easy, fast and reproducible synthesis method. Currently, in the literature, most synthesis of SPIONs are in ultra-pure water or another solvent. To consider the use of SPIONs in biomedical applications, it is essential to ensure the preservation of the physico-chemical parameters of the nanoparticles in the physiological medium to validate a synthesis process. With this objective, this study reports a comparison between the SPIONs synthesis in ultra-pure water and the SPIONs direct synthesis in a physiological serum (containing NaCl). To complete this comparison, the dispersion of SPIONs in physiological serum after an elaboration in ultra-pure water is reported. Characterizations of these different SPIONs samples are carried out to determine the physico-chemical parameters and magnetic properties. SPIONs are characterized by Transmission Electronic Microscopy, Dynamic Light Scattering, X-Ray Diffraction, Raman spectroscopy and magnetic measurements. Finally, to check if SPIONs can be used as contrast agent for MRI, a relaxometry measurement is performed.

Pesticides constitute an integral part of modern agriculture. However, there are still concerns about their effects on non-target organisms. To address this the European Commission has imposed a stringent regulatory scheme for new pesticide compounds. Assessment of the aquatic toxicity of pesticides is based on a range of advanced tests. This does not apply to terrestrial ecosystems, where the toxicity of pesticides on soil microorganisms, is based on an outdated and crude test (N mineralization). This regulatory gap is reinforced by the recent methodological and standardization advances in soil microbial ecology. The inclusion of such standardized tools in a revised risk assessment scheme will enable the accurate estimation of the toxicity of pesticides on soil microorganisms and on associated ecosystem services. In this review we (i) summarize recent work in the assessment of the soil microbial toxicity of pesticides and point to ammonia-oxidizing microorganisms (AOM) and arbuscular mycorrhizal fungi (AMF) as most relevant bioindicator groups (ii) identify limitations in the experimental approaches used and propose mitigation solutions, (iii) identify scientific gaps and (iv) propose a new risk assessment procedure to assess the effects of pesticides on soil microorganisms.

This article discusses the ways of linking physical objects to digital information relevant to chemical entities, specifically those that can be described by the use of the IUPAC International Chemical Identifier (InChI). It makes recommendations on the form of the computer readable components of labels provided for chemicals and materials that are used on product/sample containers and on the associated documentation that is used when transporting these containers (either internally or during export/import). The focus is on specification of the content of the 2D Quick Response bar codes required to describe the molecular content of the containers and link to digital resources to supplement that provided on a physical label. The necessary technical and (possible) business infrastructure necessary to support the use of the InChI and InChIKey for rapid recall of relevant information is considered here and suggestions are made.