Assessment of Sulfadiazine Accumulation Capacity of a Native Macrophyte Using Optimized Analytical Methods

MERINO MARIA BELEN; CORTES FACUNDO LEONEL; MONFERRÁN, MAGDALENA VICTORIA; WUNDERLIN, DANIEL ALBERTO; VALDÉS, MARÍA EUGENIA

Valdivia

Congreso; SETAC Latin America 14th Biennial Meeting. Latin America, Diversity of Knowledge for a Sustainable Future; 2021

SETAC LA

Antibiotics are widely used to prevent/treat animal diseases and also as growth promoters and feed additives in intensive agri- and aquaculture production. These compounds are not completely metabolized and up to 90% of them are excreted into the environment via faeces and wastewater resulting in contamination events. Phytoremediation is a possible low-cost and eco-friendly technology to remove antibiotics from contaminated water by the use of plants. Therefore, sensitive and specific quantification methodologies to measure antibiotics accumulation need to be validated. This work aimed (i) to optimize the extraction methods of three veterinary drugs (flumequine, sulfadiazine and oxytetracycline) from a native macrophyte Potamogeton pusillus and (ii) to evaluate the sulfadiazine accumulation capacity of this macrophyte under laboratory conditions. To meet the first aim, two extraction methods were evaluated through recovery tests: 1) ultrasonic extraction using different solvents, acidic and basic solutions, followed by solid phase extraction (SPE); 2) QuEChERS dispersive solid phase extraction (d-SPE) at two pH values: 2.4 and 4. Antibiotics were quantified by liquid chromatography coupled to high resolution mass spectrometry (HPLC-HRMS). Flumequine and oxytetracycline were efficiently recovered by both extraction methods (88% and 81% recovery with ultrasonic extraction, 116% and 73% with QuEChERS, respectively). The highest recovery for sulfadiazine was observed with QuEChERS at both pH evaluated (48% and 54%). On the other hand, the macrophyte was exposed to 1 mg/L sulfadiazine solution in Hoagland nutrient medium. Both total accumulation and chlorophyll content were evaluated at 3 and 7 days of exposure. Results showed that sulfadiazine was accumulated at 91±35 and 187±9 ng/g w.w., after 3 and 7 days, respectively. Chlorophyll content indicated that there was no physiological damage. Further studies are required to indicate that this macrophyte can be effectively used for removal of sulfadiazine from polluted waters.