The <scp>T</scp> hird <scp>W</scp> ay in Analytical Nanoscience and Nanotechnology

The subject matter of this article is the use of nanomaterials as tools (i.e. sorbents in microextraction techniques, optical sensors, vibrational spectroscopies, etc.) for the characterization and/or determination of nanoanalytes (analysis of the nanoworld). The so-called Third Way is the combination of the two classical approaches of analytical nanoscience and nanotechnology (AN&N), namely, the use of nanotools and determination of nanoanalytes, looking for synergies between the two nanoparticles involved in the same analytical process. After an overview of AN&N, the definition, the objectives, and the types of Third Way processes in AN&N are outlined. Moreover, examples of analytical methodologies involving the use of nanotools (i.e. sorbents in (micro)extraction techniques) for the determination of nanomaterials involving different analytical techniques (i.e. optical sensors and vibrational spectroscopies) are systematically presented. Last but not least, a critical approach to the future of these analytical nanotechnological mixed processes is discussed. Keywords: analytical chemistry; nanoscience; nanotechnology; nanotool; nanoanalyte; Third Way