Electrically Facilitated Transport of Proteins through Glass Nanopores: Electroosmosis versus Electrophoresis

Nanopores are powerful tools for single molecule detection in biotechnology. A critical challenge of nanopore detection is the large translocation speed of proteins across the nanopore. In this work, we used glass nanopores made by laser-assisted capillary pulling to investigate the transport characteristics of bovine serum albumin (BSA) driven by electrophoretic or electroosmotic flow respectively. These two flow modes are achieved by modulating the direction of the applied electric field. The experimental results demonstrate that the translocation speed of BSA through glass nanopores driven by electroosmotic flow is significantly slower than that driven by electrophoretic flow. A lower translocation speed is more favorable, which allows more events to be detected and provides more insights into biomolecular information.