Nanotechnology-based approaches for the removal of microplastics from wastewater: a comprehensive review

The increasing prevalence of microplastics (MPs) in aquatic environments has raised significant concerns due to their persistence, potential for bioaccumulation, and adverse effects on human and ecosystem health. Conventional wastewater treatment technologies are largely inadequate for effectively removing MPs, especially those in the nanosize range. This review presents a detail analysis of the sources, pathways, detection methods, and health impact of MPs, while emphasizing the emerging role of nanotechnology in their remediation. Nanomaterials, including nanoadsorbents, photocatalysts, and advanced membrane materials, exhibit unique properties such as high surface area, enhanced reactivity, and tunable surface chemistry, which offer promising avenues for the selective and efficient removal of MPs from water. This paper also explores the mechanism, performance and limitations of various nanoenabled treatment strategies such as adsorption, photocatalysis, and membrane filtration using materials like metal-organic frameworks, carbon-based nanomaterials, MXenes, and metal oxides. It also highlights recent innovations such as microrobotic systems and AI-assisted detection frameworks for MP monitoring. Despite high laboratory scale efficiencies, there are several challenges such as material scalability, environmental safety, regulatory frameworks, and real water applicability. This study proposes future directions for sustainable nanotechnology deployment, including green synthesis, hybrid system integration, and machine learning optimization. Together, these approaches aim to establish a comprehensive, scalable, and environmentally safe solution for the remediation of MPs in wastewater systems.