METHOD FOR DETECTING SMALL MOLECULES IN LIQUIDS

摘要

A method for detecting organic molecules such as benzene xylene ethylbenzene and toluene present in trace quantities in aqueous solutions is provided. The method uses a zeolite having a multiple cage structure specifically cases of two different volumes. The zeolite is chosen so that the organic molecules are able to access the zeolite on the basis of size. The small cages contain electroactive ions therein and the larger cages contain electroinactive counter cations therein. An aqueous liquid sample to be tested for small molecules is flowed into contact with the zeolite whereby at least some of the electroactive ions in the small cages are released into the aqueous liquid sample by small molecules entering the second cages and coupling with the electroactive ions in the smaller cages and exiting the zeolite. Thereafter the liquid sample is flowed into contact with an electrode downstream of the zeolite and a potential is applied to the electrode with respect to a counter-electrode effective to cause an electrochemical reaction of the electroactive ions.