Description
New PVC membrane electrodes for the determination of sulfadiazine (SDZ) are presented. The electrodes are fabricated
with conventional and tubular configurations with a graphite-based electrical contact, and no internal reference solution.
The selective membranes consist of bis(triphenylphosphoranilidene)ammonium·SDZ (electrode A), tetraoctylammonium
bromide (electrode B), or iron(II)-phthalocyanine (FePC) (electrode C) electroactive materials dispersed in a PVC matrix
of o-nitrophenyl octyl ether (o-NPOE) plasticizer. The sensors A, B, and C displayed linear responses over the
concentration ranges 1.0*10-2 – 1.0*10–5, 1.0*10–2 – 7.5*10–6, and 3.2*10–2 – 7.0* 10–6 mol l–1 (detection limits of
1.09, 2.04 and 0.87 mg ml–1) with anionic slopes of –57.3 ± 0.1, –46.7 ± 0.5, and –65.1 ± 0.2 mV decade–1, respectively.
No effect from pH was observed within 4.0 – 5.5, 4.8 – 10, and 4.5 – 8, respectively, and good selectivity was found. The
sensors were applied to the analysis of pharmaceuticals and biological fluids in steady state and in flow conditions.
; Almeida, Sofia A. A. 
