We discuss the role of nanomaterials as tools for chemical speciation.

Nanosorbents include metal oxides, noble metals and carbon-based nanomaterials.

Optical probes based on both plasmonic and fluorescent nanoparticles are described.

Nanocatalysts can promote both photooxidation and photo-chemical vapor generation.

Applications of nanoparticle-assisted speciation of As, Cr, Hg, Se, etc. are reviewed.