AF4-to-SAXS: expanded characterization of nanoparticles and proteins at the P12 BioSAXS beamline.

Biological small-angle X-ray scattering (SAXS) is a versatile and powerful technique for investigating the structural and biophysical properties of biologically and pharmaceutically relevant macromolecules and nanoparticles. SAXS offers detailed insights into macromolecular composition, size, shape and internal structure, while addressing key aspects such as oligomeric state, stability, molecular interactions, and conformational flexibility. Recently, asymmetrical-flow field-flow fractionation (AF4) was successfully coupled to SAXS, enabling online size-based fractionation and analysis of polydisperse samples.

Safe and sustainable by design of next generation chemicals and materials: SSbD4CheM project innovations in the textiles, cosmetic and automotive sectors.

The strategic objective of the Safe and sustainable by design of next generation chemicals and materials (SSbD4CheM) project is to develop screening and testing strategies for a variety of substances and materials to ensure safer and more sustainable products in line with the Sustainable Products Initiative. SSbD4CHeM is focusing on chemical safety using new approach methods, including studies without animal models and tools. Additionally, it integrates environmental sustainability for the implementation of the Safe and Sustainable by Design (SSbD) framework including risk assessment and life cycle assessment.

An integrated multimethod approach for size-specific assessment of potentially toxic element adsorption onto micro- and nanoplastics: implications for environmental risk.

Micro- and nanoscale plastics (MnPs), arising from the environmental degradation of plastic waste, pose significant environmental and health risks as carriers for potentially toxic element (PTE) metals. This study employs asymmetrical flow field-flow fractionation (AF4) coupled with multi-angle light scattering (MALS) and inductively coupled plasma mass spectrometry (ICP-MS) to provide a size-resolved assessment of chromium (Cr), arsenic (As), and selenium (Se) adsorption onto carboxylated polystyrene nanoparticles (COOH-PSNPs) of 100 nm, 500 nm, and 1000 nm. Cr exhibited the highest adsorption, with adsorption per particle surface area increasing from 9.

Quality assessment of LNP-RNA therapeutics with orthogonal analytical techniques.

The availability of analytical methods for the characterization of lipid nanoparticles (LNPs) for in-vivo intracellular delivery of nucleic acids is critical for the fast development of innovative RNA therapies. In this study, analytical protocols to measure (i) chemical composition, (ii) drug loading, (iii) particle size, concentration, and stability as well as (iv) structure and morphology were evaluated and compared based on a comprehensive characterization strategy linking key physical and chemical properties to in-vitro efficacy and toxicity. Furthermore, the measurement protocols were assessed either by testing the reproducibility and robustness of the same technique in different laboratories, or by a correlative approach, comparing measurement results of the same attribute with orthogonal techniques.

Quantitative size-resolved characterization of mRNA nanoparticles by in-line coupling of asymmetrical-flow field-flow fractionation with small angle X-ray scattering.

We present a generically applicable approach to determine an extensive set of size-dependent critical quality attributes inside nanoparticulate pharmaceutical products. By coupling asymmetrical-flow field-flow fractionation (AF4) measurements directly in-line with solution small angle X-ray scattering (SAXS), vital information such as (i) quantitative, absolute size distribution profiles, (ii) drug loading, (iii) size-dependent internal structures, and (iv) quantitative information on free drug is obtained. Here the validity of the method was demonstrated by characterizing complex mRNA-based lipid nanoparticle products.

Ex vivo models for intestinal translocation studies of cellulose nanocrystals.

Purpose: Cellulose nanocrystals (CNC) play a promising role in the development of new advanced materials. The growing demand of CNC-containing products in the food industry will lead to an increased human exposure through oral uptake. To date, there is a dearth of studies reporting on the risks which CNC pose to human health following ingestion.

Characterizing Non-covalent Protein Complexes Using Asymmetrical Flow Field-Flow Fractionation On-Line Coupled to Native Mass Spectrometry.

We report an online analytical platform based on the coupling of asymmetrical flow field-flow fractionation (AF4) and native mass spectrometry (nMS) in parallel with UV-absorbance, multi-angle light scattering (MALS), and differential-refractive-index (UV-MALS-dRI) detectors to elucidate labile higher-order structures (HOS) of protein biotherapeutics. The technical aspects of coupling AF4 with nMS and the UV-MALS-dRI multi-detection system are discussed. The "slot-outlet" technique was used to reduce sample dilution and split the AF4 effluent between the MS and UV-MALS-dRI detectors.

Physicochemical characterization and quantification of nanoplastics: applicability, limitations and complementarity of batch and fractionation methods.

A comprehensive physicochemical characterization of heterogeneous nanoplastic (NPL) samples remains an analytical challenge requiring a combination of orthogonal measurement techniques to improve the accuracy and robustness of the results. Here, batch methods, including dynamic light scattering (DLS), nanoparticle tracking analysis (NTA), tunable resistive pulse sensing (TRPS), transmission electron microscopy (TEM), and scanning electron microscopy (SEM), as well as separation/fractionation methods such as centrifugal liquid sedimentation (CLS) and field-flow fractionation (FFF)-multi-angle light scattering (MALS) combined with pyrolysis gas chromatography mass spectrometry (pyGC-MS) or Raman microspectroscopy (RM) were evaluated for NPL size, shape, and chemical composition measurements and for quantification. A set of representative/test particles of different chemical natures, including (i) polydisperse polyethylene (PE), (ii) (doped) polystyrene (PS) NPLs, (iii) titanium dioxide, and (iv) iron oxide nanoparticles (spherical and elongated), was used to assess the applicability and limitations of the selected methodologies.

Development and Characterization of a 96-Well Exposure System for Safety Assessment of Nanomaterials.

In this study, a 96-well exposure system for safety assessment of nanomaterials is developed and characterized using an air-liquid interface lung epithelial model. This system is designed for sequential nebulization. Distribution studies verify the reproducible distribution over all 96 wells, with lower insert-to-insert variability compared to non-sequential application.

Fluorescence Labeling of Cellulose Nanocrystals-A Facile and Green Synthesis Route.

Efficient chemical modification of cellulose nanocrystals (CNCs) by grafting commonly involves aprotic solvents, toxic reactants, harsh reaction conditions, or catalysts, which have negative effects on the particle character, reduced dispersibility and requires further purification, if products are intended for biomedical applications. This work, in contrast, presents a robust, facile, and green synthesis protocol for the grafting of an amino-reactive fluorophore like fluorescein isothiocyanate (FITC) on aqueous CNCs, combining and modifying existent approaches in a two-step procedure. Comparably high grafting yields were achieved, which were confirmed by thermogravimetry, FTIR, and photometry.

Influence of Physicochemical Characteristics and Stability of Gold and Silver Nanoparticles on Biological Effects and Translocation across an Intestinal Barrier-A Case Study from In Vitro to In Silico.

A better understanding of their interaction with cell-based tissue is a fundamental prerequisite towards the safe production and application of engineered nanomaterials. Quantitative experimental data on the correlation between physicochemical characteristics and the interaction and transport of engineered nanomaterials across biological barriers, in particular, is still scarce, thus hampering the development of effective predictive non-testing strategies. Against this background, the presented study investigated the translocation of gold and silver nanoparticles across the gastrointestinal barrier along with related biological effects using an in vitro 3D-triple co-culture cell model.

Analysis of complex particle mixtures by asymmetrical flow field-flow fractionation coupled to inductively coupled plasma time-of-flight mass spectrometry.

Asymmetrical flow field-flow fractionation (AF4) hyphenated with inductively coupled plasma-mass spectrometry (ICP-MS) has been widely used to characterize metal containing particles. This study demonstrates the advantages of coupling AF4 with ICP-time-of-flight mass spectrometry (ICP-TOFMS) in standard and single particle modes to determine size distribution, elemental composition, and number concentration of composite particles. The coupled system was used to characterize two complex particle mixtures.

Fast and Purification-Free Characterization of Bio-Nanoparticles in Biological Media by Electrical Asymmetrical Flow Field-Flow Fractionation Hyphenated with Multi-Angle Light Scattering and Nanoparticle Tracking Analysis Detection.

Accurate physico-chemical characterization of exosomes and liposomes in biological media is challenging due to the inherent complexity of the sample matrix. An appropriate purification step can significantly reduce matrix interferences, and thus facilitate analysis of such demanding samples. Electrical Asymmetrical Flow Field-Flow Fractionation (EAF4) provides online sample purification while simultaneously enabling access to size and Zeta potential of sample constituents in the size range of approx.

Asymmetrical Flow Field-Flow Fractionation for Sizing of Gold Nanoparticles in Suspension.

Particle size is arguably the most important physico-chemical parameter associated with the notion of a nanoparticle. Precise knowledge of the size and size distribution of nanoparticles is of utmost importance for various applications. The size range is also important, as it defines the most "active" component of a nanoparticle dose.

Multi-endpoint toxicological assessment of polystyrene nano- and microparticles in different biological models in vitro.

Nanoplastics (NP) and microplastics (MP) accumulate in our environment as a consequence of the massive consumption of plastics. Huge knowledge-gaps exist regarding uptake and fate of plastic particles in micro- and nano-dimensions in humans as well as on their impact on human health. This study investigated the transport and effects of 50 nm and 0.

Integration of Inverse Supercritical Fluid Extraction and Miniaturized Asymmetrical Flow Field-Flow Fractionation for the Rapid Analysis of Nanoparticles in Sunscreens.

We report the use of inverse supercritical fluid extraction (SFE) and miniaturized asymmetrical flow field-flow fractionation (mAF4) for the preparation and subsequent analysis of titanium dioxide nanoparticles in model and commercial sunscreens. The approach allows for the fast and reliable fractionation and sizing of TiO nanoparticles and their quantitation in commercial products. This new method represents a powerful and efficient tool for the verification of nanoparticle content in a wide range of matrixes, as demanded by recently introduced regulatory requirements.

Effect of Protein Corona on Silver Nanoparticle Stabilization and Ion Release Kinetics in Artificial Seawater.

In parallel with the growing use of nanoparticle-containing products, their release into the environment over the coming years is expected to increase significantly. With many large population centers located in near-coastal areas, and increasing evidence that various nanoparticles may be toxic to a range of organisms, biota in estuarine and coastal waters may be particularly vulnerable. While size effects may be important in cases, silver nanoparticles have been found to be toxic in large part due to their release of silver ions.