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of pyridine-free Karl Fischer reagents for volumetric water determination.
Karl Fischer volumetric titrations are widely used to quantify water content in many different samples. It is used both in industrial processes and in quality control laboratories as well.
Karl Fischer titration is well known from the beginning of 20th Century. First Karl Fischer reagents developed contained pyridine, which was supposed to be essential in the reaction.
In the original K-F reaction, iodine reacts with water in presence of SO2, methanol and pyridine.
Further experiments demonstrated that pyridine just acted as a buffer substance and it could be substituted by other basic compound, able to play the same role and, if possible, of less toxicity.
Most of the pyridine-free reagents, including our Aquagent®, contain imidazole instead of pyridine. Imidazole is a non-toxic base, has good buffering capacity and it allows fast and stable titration end-points. | 
