Overview
ISO/TS 21362:2018 - Nanotechnologies: Analysis of nano-objects using asymmetrical‑flow and centrifugal field‑flow fractionation specifies the parameters, conditions and minimal reporting needed to develop and validate methods that apply asymmetrical‑flow field‑flow fractionation (AF4) and centrifugal field‑flow fractionation (CF3) to nano‑objects and their aggregates/agglomerates dispersed in aqueous media. The Technical Specification covers integrated measurement systems that combine fractionation with one or more detectors to determine size, size distribution, concentration and material identification.
Key topics and requirements
- Scope and purpose: Method development and validation for AF4 and CF3 applied to nano‑objects in aqueous dispersions.
- Principles of operation: Fundamentals of field‑flow fractionation (FFF), with AF4 (flow field) and CF3 (centrifugal field) highlighted.
- Method development:
- Sample specifications and mobile phase selection
- Channel and membrane selection for AF4
- Injection, relaxation and optimization of flow/field programmes
- Field strength and decay programming for CF3
- Detection and analysis:
- Online sizing and concentration: multi‑angle light scattering (MALS), dynamic light scattering (DLS), UV‑Vis, fluorescence, and elemental detectors (e.g., ICP‑MS) are discussed as typical detector options
- Material identification and off‑line fraction collection
- Qualification and performance:
- System qualification, focusing performance, and carrier liquid flow control
- Method performance metrics: recovery, selectivity, retention, resolution
- Precision and measurement uncertainty considerations
- Calibration and reporting:
- Calibration of retention time for online size analysis
- Minimum reporting requirements to allow method reproduction and critical comparability of results
- Test reporting: Required apparatus, measurement parameters and recommended reporting formats.
Applications and users
ISO/TS 21362:2018 is intended for laboratories and organizations involved in:
- Nanomaterials characterization in research & development, materials discovery and nanomanufacturing
- Regulatory testing, compliance and environmental risk assessment
- Quality control in industry and analytical service labs
- Academic and government laboratories adopting AF4/CF3 as part of a nano‑characterization toolbox
Practical applications include accurate determination of nanoparticle size distribution, concentration profiling, separation of aggregates/agglomerates, and compositional analysis when coupled with appropriate detectors.
Related standards
- Prepared by ISO/TC 229 (Nanotechnologies).
- Intended to be used alongside other ISO nanotechnology specifications and instrument‑specific calibration and validation standards (see ISO/TC 229 publications for related documents).
Keywords: ISO/TS 21362:2018, AF4, CF3, field‑flow fractionation, asymmetrical‑flow FFF, centrifugal FFF, nanoparticle analysis, size distribution, nanotechnologies.