The construction and response characteristics of sensors based on polyvinyl chloride used for the assay of
ciprofloxacin (CFX) were described. The electroactive compound was the complex between ciprofloxacin and tetraphenylborate.
The wider linear concentration range 2x10-2 - 1.97x10-5mol/L was achieved when dibutylphthalate (DBP) and
bis(2-ethylhexyl)sebacate (DES) were used as plasticizers, with slopes of 29.12 and 29.55 mV per decade of concentration,
respectively, and detection limits of 3.687x10-6 and 7.362x10-6 mol/L, respectively. The optimized sensor had a fast
response (less than 5s), with good selectivities recorded versus some inorganic and organic compounds. The sensor was
successfully used for the analysis of ciprofloxacin in pharmaceutical formulation with the recoveries higher than 97.66 %,
by using a direct potentiometric method which does not require tedious sample preparation.