5 research outputs found
Environmental considerations and current status of grouping and regulation of engineered nanomaterials
This article reviews the current status of nanotechnology with emphasis on application and related environmental considerations as well as legislation. Application and analysis of nanomaterials in infrastructure (construction, building coatings, and water treatment) is discussed, and in particular nanomaterial release during the lifecycle of these applications. Moreover, possible grouping approaches with regard to ecotoxicological and toxicological properties, and the fate of nanomaterials in the environment are evaluated. In terms of potential exposure, the opportunities that arise from leveraging advances in several key areas, such as water treatment and construction are addressed. Additionally, this review describes challenges with regard to the European Commission’s definition of ‘nanomaterial’. The revised REACH information requirements, intended to enable a comprehensive risk assessment of nanomaterials, are outlined
Analytical and toxicological aspects of nanomaterials in different product groups: Challenges and opportunities
The widespread integration of engineered nanomaterials into consumer and industrial products creates new challenges and requires innovative approaches in terms of design, testing, reliability, and safety of nanotechnology. The aim of this review article is to give an overview of different product groups in which nanomaterials are present and outline their safety aspects for consumers. Here, release of nanomaterials and related analytical challenges and solutions as well as toxicological considerations, such as dose-metrics, are discussed. Additionally, the utilization of engineered nanomaterials as pharmaceuticals or nutraceuticals to deliver and release cargo molecules is covered. Furthermore, critical pathways for human exposure to nanomaterials, namely inhalation and ingestion, are discussed in the context of risk assessment. Analysis of NMs in food, innovative medicine or food contact materials is discussed. Specific focus is on the presence and release of nanomaterials, including whether nanomaterials can migrate from polymer nanocomposites used in food contact materials. With regard to the toxicology and toxicokinetics of nanomaterials, aspects of dose metrics of inhalation toxicity as well as ingestion toxicology and comparison between in vitro and in vivo conclusions are considered. The definition of dose descriptors to be applied in toxicological testing is emphasized. In relation to potential exposure from different products, opportunities arising from the use of advanced analytical techniques in more unique scenarios such as release of nanomaterials from medical devices such as orthopedic implants are addressed. Alongside higher product performance and complexity, further challenges regarding material characterization and safety, as well as acceptance by the general public are expected
Model Peptides Uncover the Role of the β‑Secretase Transmembrane Sequence in Metal Ion Mediated Oligomerization
The
β-secretase or β-site amyloid precursor protein cleaving
enzyme 1 (BACE1) is the enzyme responsible for the formation of amyloid-β
peptides, which have a major role in Alzheimer pathogenesis. BACE1
has a transmembrane sequence (TMS), which makes it unique among related
proteases. We noticed that the BACE1 TMS contains an uncommon sulfur-rich
motif. The sequence MxxxCxxxMxxxCxMxC spans the entire TMS, resembles
metal ion binding motifs, and is highly conserved among homologues.
We used a synthetic 31-mer model peptide comprising the TMS to study
metal ion binding and oligomerization. Applying diverse biochemical
and biophysical techniques, we detected dimer and trimer formation
of the TMS peptide with copper ions. Replacement of the central Cys466
by Ala essentially abolished these effects. We show that the peptide
undergoes a redox reaction with copper ions resulting in a disulfide
bridge involving Cys466. Further, we find peptide trimerization that
depends on the presence of monovalent copper ions and the sulfhydryl
group of Cys466. We identified Cys466 as a key residue for metal ion
chelation and to be the core of an oligomerization motif of the BACE1-TMS
peptide. Our results demonstrate a novel metal ion controlled oligomerization
of the BACE1 TMS, which could have an enormous therapeutic importance
against Alzheimer disease
Environmental considerations and current status of grouping and regulation of engineered nanomaterials
This article reviews the current status of nanotechnology with emphasis on application and related environmental considerations as well as legislation. Application and analysis of nanomaterials in infrastructure (construction, building coatings, and water treatment) is discussed, and in particular nanomaterial release during the lifecycle of these applications. Moreover, possible grouping approaches with regard to ecotoxicological and toxicological properties, and the fate of nanomaterials in the environment are evaluated. In terms of potential exposure, the opportunities that arise from leveraging advances in several key areas, such as water treatment and construction are addressed. Additionally, this review describes challenges with regard to the European Commission’s definition of ‘nanomaterial’. The revised REACH information requirements, intended to enable a comprehensive risk assessment of nanomaterials, are outlined