Sulfadiazine-selective determination in aquaculture environment: Selective potentiometric transduction by neutral or charged ionophores

Abstract

A B S T R A C TSolid-contact sensors for the selective screening of sulfadiazine (SDZ) in aquaculture waters are reported. Sensor surfaces were made from PVC membranes doped with tetraphenylporphyrin-manganese(III) chlo-ride, a-cyclodextrin, 13-cyclodextrin, or 1-cyclodextrin ionophores that were dispersed in plasticizer. Some membranes also presented a positive or a negatively charged additive. Phorphyrin -based sen-sors relied on a charged carrier mechanism. They exhibited a near-Nernstian response with slopes of 52 mV decade −1 and detection limits of 3.91 × 10 −5 mol L −1 . The addition of cationic lipophilic compounds to the membrane originated Nernstian behaviours, with slopes ranging 59.7-62.0 mV decade −1 and wider linear ranges. Cyclodextrin-based sensors acted as neutral carriers. In general, sensors with positively charged additives showed an improved potentiomet ric performance when compared to those without additive. Some SDZ selective membranes displayed higher slopes and extended linear concentration ranges with an increasing amount of additive (always <100% ionophore). The sensors were independent from the pH of test solutions within 2-7. The sensors displayed fast response, always <15 s. In general, a good discriminating ability was found in real sample environment. The sensors were successfully applied to the fast screening of SDZ in real waters samples from aquaculture fish farms. The method offered the advantages of simplicity, accuracy, and automation feasibility. The sensing membrane may contribute to the development of small devices allowing in locus measurements of sulfadiazine or parent-drugs.K e y w o r d s Sulphadiazine, Cyclodextrin-based ionophore, Porphyrin-based ionophore, Sensor, Potentiometry

A cellulose-based colour test-strip for equipment-free drug detection on-site: application to sulfadiazine in aquatic environment

“…The overall procedure is inexpensive, expeditious and quick, having no environmental impact. A comparison of this method to previous recently published chemical sensing systems [32,35,[49][50][51][52] may be established by checking Table 1, highlighting that the herein proposed method is highly simple in terms of synthesis (summarized in Figure S16) and analytical application.…”

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New and low cost plastic membrane electrode with low detection limits for sulfadimethoxine determination in aquaculture waters

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“…Taken (ng/mL) Found (ng/mL) Recovery (%) macrocyclic binds sulphonamide antimicrobial drugs [22] and it was therefore selected as a possible ligand, for concentrations of tiometric response. Carbonate, chlorate, chloride, chromate, cyanide, fluoride, hydrogenocarbonate, nitrate, nitrite, persulphate, phosphate, salicylate and sulphate were considered for this purpose.…”

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