Preparation and Properties of the Hybrid Material n‐Propyl(3‐methylpyridinium)silsesquioxane Chloride. Application in Electrochemical Determination of Nitrite

The synthesis and properties of the ion exchange polymer 3‐n‐propyl(3‐methylpyridinium)silsesquioxane chloride (SiPy⁺Cl^?) are described. Based on the Langmuir model, the equilibrium constant at the solid‐solution interface for the reaction, SiPy⁺Cl^?+NO ?SiPy⁺NO , was calculated for nitrite adsorption. The value found, β=8.7×10³ L mol^?1, indicates good affinity of the anion for the solid phase. A carbon paste electrode of the material was tested for NO oxidation and a linear response, in the concentration range between 6.3 and 143.6 μmol L^?1, was obtained by amperometry. The analytical applicability of the proposed system was ascertained by the satisfactory results attained in its application to monitoring of nitrite in natural waters.