Overview
ISO/TS 19807-2:2021 is a technical specification in the ISO nanotechnologies series that defines the characteristics and measurement methods for nanostructured magnetic beads used in nucleic acid extraction. The document covers magnetic beads supplied as suspensions or powders that contain a substantial fraction of magnetic nanoparticles (including superparamagnetic particles). It lists critical bead and suspension characteristics, suggests applicable analytical methods, and defines reporting elements for sample preparation and test reports. Health, safety and environmental aspects are outside the scope.
Key topics and requirements
This specification identifies measurable properties and recommended test approaches rather than prescriptive performance limits. Key technical topics include:
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Bead composition and form
- Bead mass concentration (suspension or powder)
- Dispersing medium and operational time / shelf life
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Physical and morphological characteristics
- Bead size and bead size distribution
- Mass-specific surface area (e.g., BET)
- Size of primary magnetic nanoparticles (TEM, SEM)
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Surface chemistry and binding
- Surface functional group type and density (XPS, IR)
- Nucleic acid binding capacity under specified conditions
- Surface-modification descriptors relevant to DNA/RNA capture
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Magnetic properties
- Saturation mass magnetization
- Remanent mass magnetization
- Initial magnetic mass susceptibility (VSM, SQUID)
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Chemical composition and purity
- Iron ion concentration (ICP-OES)
- Other compositional descriptors (UV-Vis, elemental analysis)
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Measurement methods and reporting
- Lists applicable techniques: DLS, TEM, SEM, BET, VSM, SQUID, ICP-OES, XPS, IR, UV-Vis
- Guidance on sample preparation and required information in a test report
Practical applications
ISO/TS 19807-2 supports consistency, comparability and transparency in products and test data for magnetic beads used in:
- Molecular biology and genomics sample prep (DNA/RNA extraction)
- Diagnostic kit development (including liquid biopsy and ctDNA/cfDNA workflows)
- Clinical and research laboratories performing nucleic acid isolation
- Manufacturers and quality control (QC) teams standardizing bead production and batch release
By standardizing characterization and measurement methods, the specification helps ensure reliable nucleic acid recovery, reproducible kit performance, and clearer product specifications for end users.
Who should use this standard
- Magnetic bead manufacturers and formulators
- Diagnostic and reagent kit developers
- Analytical and QC laboratories
- Regulatory bodies evaluating product claims
- Research groups working with magnetic separation and biosample preparation
Related standards
Keywords: nanotechnologies, magnetic nanomaterials, magnetic beads, nucleic acid extraction, superparamagnetic beads, bead size distribution, saturation mass magnetization, nucleic acid binding capacity, BET, VSM, ICP-OES.