Preliminary experiments revealed that suitable conditions for
dissolving Zn(II)–PAN complex in aqueous solution could be
achieved by adding some non-ionic surfactants such as Tween-
80, Triton X-100, poly(vinylalcohol) were successively at different
concentrations (0.1–1.0%, v/v) into the reaction medium.
Preliminary experiments pointed out those cationic surfactants
could not be used for this purpose. In fact, the analytical signal
was not observed in the presence of cetyltrimethylammonium
or cetrypriridinium chloride, in view of the hydration caused by
the ionic group [30] that reduced the molecular forces impairing
the dissolution, thus the establishment of the organized
medium. Cationic surfactants were then not investigated further.
Among the different non-ionic surfactants tested, Triton X-100
was selected because the attainable sensitivity was the highest.