(LB/PAn-PTSA/GCE) has been used for the detection of trace concentrations of Ag . UV–vis abso
spectra indicated that the PAn was doped by PTSA. The surface morphology of the PAn LB ?lm wa
acterized by atomic force microscopy (AFM). The electrochemical properties of this LB/PAn-PTS
were studied using electrochemical impedance spectroscopy (EIS) and cyclic voltammetry. The L
PTSA/GCE was used as a voltammetric sensor for determination of trace Ag＋ at pH 5.0 using
scanning stripping voltammetry. Under the optimal experimental conditions， the stripping curre
proportional to the Ag＋ concentration over the range from6.0×10?10 mol L?1 to 1.0×10?6 mol L?
a detection limit of 4.0×10?10 mol L?1. The high sensitivity， selectivity， and stability of this L
PTSA/GCE also demonstrated its practical utility for simple， rapid and economical determination
in water samples.
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