Confined Nanopipette-A new microfluidic approach for single cell analysis

Monitoring the dynamic behaviour of a single cell in a natural environment is vital in biological studies and contributes to the understanding of the relationship between the function of single cells and the pathology. The advent of specially designed and sensitive chemical or biological analytical methods that enable the application in single cell analysis is urgently demanded. Confined nanopipettes, a unique microfluidic channel with a tunable size, have been proven to be a facile approach capable of identifying small molecules in a label-free manner. The microfluid in the confined space and the electrochemically confined effect within the nanopipette renders a high sensitivity to the analytes of individual cells. In contrast to ensemble analytical techniques, nanopipettes can precisely manipulate single cells with submicron accuracy. Here, we review the fabrication and characteristics of confined nanopipettes, summarize their application in single cell analysis, and conclude with a perspective for their future development in the single cell analysis area. (C) 2019 Elsevier B.V. All rights reserved.