Differential pulse voltammetric determination of P(V) following adsorptive accumulation of alpha-[PMo(12)O(40)](3-) on a polypyrrole-modified glassy carbon electrode.
On the basis of the formation and pre-concentration of an alpha-Keggin-type [PMo(12)O(40)](3-) complex, a novel voltammetric method was developed for the determination of trace levels of P(V). The alpha-[PMo(12)O(40)](3-) complex was formed by heating a 5x10(-4) M Mo(VI)-0.2 M HCl-40% (v/v) CH(3)CN system containing a trace amount of P(V) at 70 degrees C for 30 min. During the electrochemical polymerization of pyrrole in the alpha-[PMo(12)O(40)](3-) solution, the alpha-[PMo(12)O(40)](3-) complex was accumulated into the polypyrrole film on a glassy carbon electrode. The differential pulse voltammetric peak current due to the alpha-[PMo(12)O(40)](3-) complex incorporated in the polypyrrole film was linearly dependent on the P(V) concentration in the range of 5x10(-9)-5x10(-7) M; a detection limit of 2x10(-9) M was achieved.
Takamoto
Masayo
M
Faculty of Science, Department of Chemistry, Kobe University, Nada, Kobe 657-8501, Japan.
Himeno
Sadayuki
S