Biosensing at the nanoscale: There's plenty of room inside

Starting with the pioneering work of Cleland, Horrocks and Houlton [J. Chem. Soc.-Faraday Trans., 91 (1995) 4001], one of the chief applications of Si surface functionalization is chemical sensing. Grafting and assembling molecules onto Si surfaces has shown over the years to be a highly effective and efficient way to make semiconductor surfaces sensitive to chemical species, leading to novel classes of chemical sensors. The concurrent progress of device miniaturization and the more recent capability of getting functionalized systems down to the nanoscale has disclosed novel avenues to biosensing. Aim of this review is to analyze the most recent advancements in this field. Special emphasis will be placed on the fascinating possibilities opened by sensors operating with nanometric space resolution, discussing the potentials and the hurdles still on the way to use them for subcellular biosensing. © 2011 American Scientific Publishers.