Metrohm takes the opportunity to provide a counter-argument to a recent marketing campaign promoting 'reagent-free' chromatography
To any analytical chemist it is obvious that a given analytical problem in ion chromatography can be solved best by choosing the optimum column and the optimum eluent.
Nevertheless a recent marketing campaign suggests to use so-called 'reagent-free' ion chromatography.
First of all, says Metrohm, for anion separation this method uses potassium hydroxide as an eluent and by all means potassium hydroxide is a reagent.
For cation separations methanesulphonic acid is the eluent.
And no chemist doubts that this is a reagent too.
One eluent fits all? It is more than obvious that a single reagent for all anions and cations cannot perform as well as a specifically chosen and composed eluent with optimum eluent strength and customised chemical properties.
This reminds one of the merchandising of socks being promoted with the argument that 'one size fits all'.
In conclusion: this so-called 'reagent-free' IC does need reagents indeed which the customer has to purchase in the form of cartridges filled with chemicals which subsequently form the eluent.
A further fact is that potassium hydroxide is not a very strong eluent.
And the cartridges have to be disposed of as hazardous waste.
No reagent - but hazardous waste instead? Metrohm recommends for instance carbonate based or other eluents which are far more specific and tailor-made for a given anion separation problem.
And similarly it suggests the use of optimised application-specific eluents for cation separation.
