Overview
ISO 13276:2020 specifies a gravimetric method for determining nicotine purity using tungstosilicic acid. The standard applies to pure nicotine and nicotine salts used as calibration materials in analytical testing of tobacco, tobacco products and smoke. The method is based on forming an insoluble nicotine silicotungstate precipitate which is collected, dried/ignited and weighed to calculate purity.
Key topics and technical requirements
- Principle: complex formation of nicotine (or nicotine salts) with tungstosilicic acid to produce an insoluble precipitate (nicotine silicotungstate) whose mass is measured gravimetrically.
- Reagents: analytical-grade reagents and distilled (or equivalent) water. Specification of a dodeca-tungstosilicic acid solution and hydrochloric acid solutions (20% and 0.1% dilutions) are provided.
- Sample and quantities: typical sample mass ≈ 0.1 g per replicate; recommended multiple replicates (example: five).
- Filtration options:
- Glass-filter (sintered Gooch crucible) procedure with oven drying at (120 ± 5) °C to constant mass.
- Filter paper procedure: ashless filter paper, transfer to porcelain/platinum crucible and ignition/combustion at >600 °C (furnace or Bunsen burner).
- Apparatus accuracy: analytical balance with 0.1 mg resolution; appropriate ovens, furnaces, sintered crucibles, ashless filter papers.
- Expression of results: nicotine purity reported as mass percent, calculated from the dried precipitate mass and a nicotine-equivalent factor that depends on the filtration procedure (factors provided in the standard). Results are averaged across replicates and reported to one decimal place.
- Performance: the standard includes repeatability and reproducibility data from interlaboratory studies (values for pure, degraded and tartrate forms are given).
- Safety: the document contains a warning about hazardous materials and the user’s responsibility to apply appropriate safety and health practices.
Applications and users
ISO 13276:2020 is used by:
- Tobacco and nicotine testing laboratories for calibration and verification of analytical nicotine assays.
- Manufacturers and suppliers of nicotine standards and reference materials.
- Regulatory and forensic laboratories performing smoke and product analysis.
- Research groups validating analytical methods or conducting interlaboratory comparisons.
Practical benefits include a standardized, well-characterized gravimetric procedure for producing nicotine purity values suitable for calibration, method validation and quality control.
Related standards
- ISO/IEC 17025 - General requirements for the competence of testing and calibration laboratories (referenced for laboratory competence and reporting).