Adsorptive stripping voltammetry of a fentanyl derivative at a mercury electrode

In a supporting electrolyte of NaOH, a pair of cathodic and anodic peaks of N,N'-diphenyl-N,N'-bis(1-phenylmethyl-4-piperidinyl)-ethanediamide (DBPPE) is found by cyclic voltammetry at a Hg electrode. The cathodic and anodic peak potentials are -1.53 and -1.46 V (vs. Ag/AgCl), respectively. The cathodic peak shows adsorptive characteristics when the concentration of DBPPE is low and the preconcentration time is long. The adsorbed species is most probably the DBPPE neutral molecule. The method for measuring trace amount of DBPPE by adsorptive stripping voltammetry is established and the detection limit can reach 5 x 10(-9)M with a 6-min preconcentration.