The effect of silica-magnetite nanoparticles on the ecotoxicity of the antibiotic ciprofloxacin

Abstract

Increasing production and application of engineered nanomaterials including nanoparticles (NPs) lead to their discharge into the environment, where they can interact with co-existing antibiotics from wastewaters, causing complicated joint effect to organisms that needs to be studied. Herein a typical engineered nanomaterial, silica-magnetite NPs modi ed with tetraethoxysilane and 3aminopropyltriethoxysilane (MTA-NPs, 1-2 g/L), and a common antibiotic cipro oxacin (CIP, 0-5 mg/L) were selected as the analytes. Their joint toxicity to a model ciliates infusoria Paramecium caudatum was speci cally investigated. The impact of CIP, MTA-NPs and humic acids (HA) was tracked for 24 h individually and collectively on the survival of infusoria. The addition of MTA-NPs and HA at the studied concentrations lead to the survival of 60% of organisms. The combined presence of the MTA-NPs at a concentration of 1.5-2 mg/L and НА at a concentration of 20-45 mg/L has a multiplier effect and allows increasing the survival rate of ciliates > 70% due to the enhanced removal of CIP.