Biomimetic solid-state nanochannels for chemical and biological sensing applications

Biomimetic solid-state nanochannels enable new modalities for biosensing. In the last decade, these nanofluidic architectures have been widely studied due to their rapid and sensitive detection capabilities. Developing nanofluidic sensors with great ability to sense ions, small biomolecules, and biological macromolecules requires the combination of versatile surface modification strategies with reliable nanofabrication techniques. Solid-state nanochannels display unique ion transport properties and appealing effects arise when their inner surfaces are charged and the confinement length scale is comparable to the range of the electrostatic interactions in solution. In this context, the integration of molecular recognition elements into the nanochannels yields novel nanofluidic elements with tailored sensoric functions. This review describes recent advances in solid-state nanochannel-based (bio)chemical sensors. The topics covered in this work include sensing principles, nanofabrication techniques and strategies adopted for detecting specific targets, such as ions, small molecules, proteins or nucleic acids, among others. The review highlights several exceptionally promising research directions and discusses how the interplay between the interface chemistry, governed by the bio-receptors, and the remarkable ion transport properties of nanochannels plays a critical role in the analytical performance of the developed devices. In the end, we also offer our vision of the future prospects of this field of research.