63443 2025 eng lecture 0 -- -- -- Engineered nanoparticles have a large application potential in fields such as medicine, sensing, catalysis, energy storage, and opto-electronics [1]. The applicability and performance of engineered nanoparticles is largely determined by their surface chemistry, i.e. functional groups and ligands on the particle surface. However, documented standards to quantify functional groups and ligands currently do not exist. Such standards are required to support quality control of nanomaterial production and surface modification processes, and safe-by-design concepts and to meet regulatory requirements. Here, this issue is addressed by developing and standardizing quantitative Nuclear Magnetic Resonance (qNMR) methods for the characterization of surface functionalized nanoparticles which specifically address the determination of the amount and chemical composition of surface functionalities and coatings. This work is being developed under the EMP project 23NRM02 SMURFnano - Standardised measurements of surface functionalities on nanoparticles. qNMR competence of 7 qNMR laboratories involved in the project was first tested with a molecular model sample i.e. citrate, to be assessed in terms of purity. Citrate is often used as hydrophilic surface ligand for different nanoparticles. Then, the first nanoparticle samples, here a set of aminated SiO2 NPs [1] with a particle size of 100 nm and two amino group densities, prepared and characterized by BAM regarding size and surface charge as well as stability over 21 months with an optical assay and qNMR, were assessed in an international interlaboratory comparison (ILC) on qNMR. Thereby, the amount of surface amino groups introduced by grafting of the silica cores with different amounts of 3-aminopropyl)triethoxysilane (APTES) was quantified by each participant following a sample preparation protocol previously developed by BAM and NRC.The results of the ILC were then used to refine the protocol for sample preparation and to identify critical points for qNMR measurement and data analysis. This work will contribute to the development of a Preliminary Work Item (PWI) 19257 (ISO/TC 229) on surface functional groups and coatings on nano-objects. Also, it will lay the groundwork to perform ILCs on the quantification and determination of the amount of surface functional groups under the roof of VAMAS TWA2 (Surface Chemical Analysis) for different types of nanomaterials possessing industry-relevant surface functionalities using qNMR. These ILCs will be complemented by other techniques like X-Ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS). BERM Halifax, Canada 01.06.2025 04.06.2025 0 publish false true C. Portesi eng uncontrolled Quality assurance eng uncontrolled Nano eng uncontrolled Particle eng uncontrolled Synthesis eng uncontrolled Advanced materials eng uncontrolled Characterization eng uncontrolled Electron microscopy eng uncontrolled Silica eng uncontrolled Surface eng uncontrolled qNMR eng uncontrolled Optical assay eng uncontrolled Interlaboratory comparison eng uncontrolled Metrology eng uncontrolled Validation eng uncontrolled Standardization Analytische Chemie Ingenieurwissenschaften und zugeordnete Tätigkeiten 1 Analytische Chemie; Referenzmaterialien 1.4 Non-Target-Analytik 1.2 Biophotonik 6 Materialchemie 6.1 Oberflächen- und Dünnschichtanalyse Material Chemie und Prozesstechnik Chemische Charakterisierung und Spurenanalytik Datei im Netzwerk der BAM verfügbar ("Closed Access") Präsentation Advanced Materials