Clean Water and Sanitation (SDG 6), Climate Action (SDG 13)
Selective extraction through greener molecular imprinting routes and non-selective extraction of pharmaceuticals in water for environmental monitoring in South Africa
Lawrence Madikizela University of South Africa, Johannesburg, South Africa. E-mail: madiklm@unisa.ac.za
Recently, the occurrence of a wide range of pharmaceuticals including non-steroidal anti-inflammatory drugs, antibiotics, and antiretroviral drugs have been reported in South African waters. In this work, a detailed analysis of pharmaceuticals through non-target analysis resulted in the detection of 47 pharmaceuticals in river water with 31 drugs found present for the first time in South African waters, while 7 were not recognized as South African medications. The analytical approach made use of solid- phase extraction and ultra-high-performance liquid chromatography-quadrupole time-of-flight-mass spectrometry (UHPLC-QTOF-MS). Other novel work involved the synthesis of molecularly imprinted polymers (MIPs) for selective extraction of antiretrovirals in river water. Green monomers such as ionic liquids and deep eutectic solvents for molecular imprinting were explored. Notably, aliquat 336 was used as the functional monomer to produce a MIP that selectively recognized abacavir in aqueous samples (maximum adsorption capacity of 5.98 mg/g). Among the detected pharmaceuticals in South African surface waters include acetaminophen with the highest concentration of 430 ng/L, while oxolinic acid with the highest hazard quotient of 48.6 indicated a risk of toxicity to aquatic organisms. The fate of pharmaceuticals in the South African environment is not well-understood with recent work showing their occurrence in seawater. Key words: Sample preparation; selectivity; antiretroviral drugs; Contamination
P54
© The Author(s), 2025
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