Metal-based nanoparticles and nanohybrids for sensing and remediation of environmental pesticides

Nanotechnology is an emerging field in engineering, health science, and environmental management. Recent studies have advocated the potential scope of nanoparticles and nanohybrids in pesticide sensing and removal from environmental samples. Metal oxide nanoparticles, metallic and bimetallic nanoparticles, halloysite, and carbon nanotubes have shown their efficacy in pesticide remediation. These materials can be coupled with conventional colorimetric, Surface Plasmon Resonance, fluorescence-based, aptameric, and enzyme-based approaches to detect pesticides belonging to organophosphate, organochlorine, carbamate, neonicotinoid, and atrazine groups. Degradation mechanisms like hydrolysis, photocatalysis, oxidation, and ozonation are employed by nanotechnology to remove pesticides from water and soil samples. However, certain issues like scalability, unavailability of rigorous testing protocols, and lack of uniform regulatory frameworks for nanomaterial synthesis limit its usage. Moreover, toxicity profiles of the majority of nanomaterials are lacking. Studies indicate that nanomaterials can be cytotoxic. Therefore, safety is another major concern. Hence, the present review aims to discuss the recent advances in nanoparticle and nanohybrid-mediated sensing and the removal of pesticides from real samples. Moreover, the chemistry behind pesticide sensing and removal will also be delineated. Finally, the review sheds light on existing limitations associated with nanomaterial-based pesticide sensing and remediation at the global scale.