Analytical nanotechnology for food analysis

Nanotechnology involves the study and use of materials at nanoscale dimensions (nanomaterial sizes of ≤100 nm), exploiting the different physiochemical properties exhibited by these nanomaterials from the same materials at a larger scale. Nanotechnology is being demonstrated to have a large impact on many aspects of food and agricultural systems, from the development of new food packing materials to nano-delivery systems, including the analytical control of the whole food chain. In fact, the need to generate fast, reliable and precise information on the quality and security of foodstuffs and food industry has resulted in an intensive search for more selective and sensitive analytical methods. Nanotechnology is one way to achieve these goals. Although analytical nanotechnology applied to food industry is still an emerging field, chemical sensor and biosensor technology for use in this area has rather early taken advantage of the unique merits of nanotechnology and nanomaterials. This article reviews the recent progress made in analytical nanotechnology as applied to the food industry and to food analysis, with particular emphasis on nano-sensing. A brief description of the various nano-based sensing approaches is given and their capabilities and limitations are discussed. Typical examples are presented for exogenous compounds (e.g. pesticides, toxic anions, ripening gases or vitamin supplements) and endogenous compounds (from microorganisms to vitamins) in food. In addition, selected nanotechnology-based analytical methods other than sensing are described.