Overview
ISO 2881:1992 - Tobacco and tobacco products - Determination of alkaloid content - Spectrometric method specifies a reference analytical procedure for measuring total alkaloids expressed as nicotine in unmanufactured tobacco, manufactured tobacco and tobacco products. The method combines steam distillation under strongly alkaline conditions with UV‑spectrometric measurement of the acidified distillate and calculation of nicotine content on a water‑free basis.
Key topics and technical requirements
- Principle: Steam‑distill ground, dried tobacco under alkaline conditions; collect and acidify the distillate; measure UV absorbance and calculate alkaloids as nicotine.
- Reagents: analytical grade reagents including sodium chloride, sodium hydroxide (c = 8 mol·L‑1), concentrated and dilute sulfuric acid (as specified), and a nicotine standard (≥98 % purity).
- Apparatus:
- Steam distillation apparatus (as per ISO 3401 or equivalent) validated for ≥98 % recovery with a nicotine check.
- UV spectrometer covering 230–290 nm and matched quartz cells with 1 cm pathlength.
- Grinder, 500 µm sieve, drying oven (≤40 °C), volumetric flasks and pipettes.
- Sample preparation:
- Dry test sample (≤40 °C), grind to pass a 500 µm sieve (do not grind >2 minutes to avoid heat loss of alkaloids).
- Typical distillate collection: 220–230 mL at a rate of 10–12 mL/min.
- Measurement:
- Dilute aliquot of acidified distillate; measure absorbance at 236, 259 and 282 nm against an acid blank.
- Use the stated absorptivity at 259 nm (given in the standard) and the provided formulae to compute mg nicotine and percent nicotine on a water‑free basis.
- Quality & repeatability:
- Procedural check: recovery ≥98 % with pure nicotine.
- Repeatability requirement: two determinations by the same analyst should not differ by more than 0.05 % (expressed as nicotine).
Applications and who uses it
- Tobacco industry QC and manufacturing laboratories - routine batch testing, process control and product specification.
- Contract testing and analytical service labs - standardized method for inter‑laboratory comparability.
- Regulatory and public‑health laboratories - compliance testing and monitoring of nicotine/alkaloid levels in products.
- R&D and academic researchers - formulation studies, ingredient profiling and comparative analyses.
Practical uses include labeling verification, product development, supply‑chain quality checks and toxicological exposure assessment where accurate nicotine quantification is required.
Related standards
- ISO 3401 (distillation apparatus validation), ISO 4874 and ISO 8243 (sampling), ISO 6488 (water determination), ISO 565 (sieves). These referenced standards support sampling, apparatus and supporting measurements required by ISO 2881:1992.
Keywords: ISO 2881:1992, tobacco alkaloid determination, nicotine analysis, spectrometric method, steam distillation, tobacco testing, analytical standard.