Overview
ISO/TR 13097:2013 - "Guidelines for the characterization of dispersion stability" provides practical guidance for assessing the physical stability of liquid dispersions (suspensions, emulsions, foams and combinations). The Technical Report defines dispersion stability in terms of changes in one or more physical properties over time and focuses on kinetic/thermodynamic instability (not chemical, enzymatic or microbial degradation). It covers measurement choices, acceleration procedures, and approaches to predict or estimate shelf life.
Key topics and technical requirements
- Definition of stability: stability metrics (what to monitor) and stability criteria (acceptable deviations) for a given product and use case.
- Mechanisms of instability: agglomeration, aggregation, coalescence, creaming, sedimentation, Ostwald ripening, phase inversion and phase separation.
- Characterization approaches:
- Direct methods - direct observation and measurement of state changes (e.g., particle/droplet size distribution, separation layers).
- Correlative methods - indirect measurements correlated to stability (e.g., rheology, zeta potential, turbidity).
- Acceleration procedures - validated accelerated aging tests to speed evaluation of long-term stability while preserving relevant mechanisms.
- Data evaluation & shelf-life prediction:
- Comparative analysis for ranking formulations.
- Predictive analysis to estimate shelf life from observed rates of change and product specifications.
- Measurement selection guidance - choose metrics that reflect the product’s functional quality; no single parameter universally characterizes stability.
- Annex A compiles relevant international and national standards to support measurement and method selection.
Practical applications
ISO/TR 13097:2013 is applicable throughout the product lifecycle:
- Formulation & R&D - guiding selection of stabilizers (electrostatic, steric, electrosteric), optimizing droplet/particle properties and continuous-phase rheology.
- Quality control & manufacturing - setting stability criteria, monitoring process consistency, and validating accelerated tests.
- Shelf-life estimation & product labeling - deriving storage recommendations from measured instability rates.
- Instrument manufacturers & testing labs - aligning measurement methods and reporting practices with an internationally recognized framework.
Who should use it
- Formulation scientists (cosmetics, paints, food, pharmaceuticals, agrochemicals)
- QC/analytical laboratories and production engineers
- Regulatory and compliance teams assessing product stability claims
- Instrument vendors and method developers
Related keywords: ISO/TR 13097:2013, dispersion stability, characterization, suspension stability, emulsion stability, stability metrics, accelerated aging, shelf life, sedimentation, creaming, Ostwald ripening, DLVO.