Carbon-based materials as promising sorbents for analytical sample preparation: Recent advances and trends in extraction of toxic metal pollutants from various media

The extraction of heavy metal ions from different matrices is a critical aspect of environmental monitoring and analysis. The sorbent-based techniques provide a valuable platform for extraction of heavy metals, particularly from liquid media and their efficiency is influenced by the choice of sorbent, as it governs the physical and chemical interactions with the analyte. In this review, we discussed the role of carbon-based sorbents in extraction of heavy metal ions from environmental, biological, and food samples as they stand out due to their remarkable adsorption efficiency, versatility, and widespread application. They have been classified into carbon nanotubes and their composites, graphene-based materials or composites, and other carbon-based materials. The synthesis aspects that enhance extraction capabilities and selectivity for specific heavy metal ions are discussed. An overview of sorbent-based extraction techniques where carbon-based materials are employed is provided. A brief account of limitations, challenges, and future dimensions is also provided.