Oral two-generation reproduction toxicity study with NM-200 synthetic amorphous silica in Wistar rats.

Synthetic amorphous silica (SAS) like NM-200 is used in a wide variety of technological applications and consumer products. Although SAS has been widely investigated the available reproductive toxicity studies are old and do not cover all requirements of current OECD Guidelines. As part of a CEFIC-LRI project, NM-200 was tested in a two-generation reproduction toxicity study according to OECD guideline 416.

Toxicity assessment of aggregated/agglomerated cerium oxide nanoparticles in an in vitro 3D airway model: the influence of mucociliary clearance.

We investigated the toxicity of aggregated nanoparticles of cerium oxide (CeO2) using an in vitro 3D human bronchial epithelial model that included a mucociliary apparatus (MucilAir™). CeO2 was dispersed in saline and applied to the apical surface of the model. CeO2 did not induce distinct effects in the model, whereas it did in BEAS-2B and A549 cell cultures.

Rapidly in situ forming biodegradable robust hydrogels by combining stereocomplexation and photopolymerization.

Our previous studies have shown that stereocomplexed hydrogels can be rapidly formed in vitro as well as in vivo upon mixing aqueous solutions of eight-arm poly(ethylene glycol)-poly(l-lactide) (PEG-PLLA) and poly(ethylene glycol)-poly(d-lactide) (PEG-PDLA) star block copolymers. In this study, stereocomplexation and photopolymerization are combined to yield rapidly in situ forming robust hydrogels. Two types of methacrylate-functionalized PEG-PLLA and PEG-PDLA star block copolymers, PEG-PLLA-MA and PEG-PDLA-MA, which have methacrylate groups at the PLA chain ends and PEG-MA/PLLA and PEG-MA/PDLA, which have methacrylate groups at the PEG chain ends, were designed and prepared.

High molecular weight supramolecular polymers containing both terpyridine metal complexes and ureidopyrimidinone quadruple hydrogen-bonding units in the main chain.

Using a hydroxy-functionalized terpyridine as initiator, a poly(epsilon-caprolactone) containing one terpyridine endgroup was prepared by tin octanoate-catalyzed controlled ring-opening polymerization. The omega-hydroxy group of this polymer was subsequently reacted with an isocyanato-ureidopyrimidinone, resulting for the first time in polymers bearing a metal-coordinating ligand on the one and a hydrogen-bonding unit on the other chain end. Hydrogen-bonded supramolecular dimers were shown to be present in chloroform solution.