A simple electrochemical methodology for evaluation of the velocity of electroosmotic flow at the tip of polarized microcapiliary.

摘要

A simple electrochemical methodology for evaluation of the velocity of electroosmotic flow at the tip of a polarized glass microcapiliary is presented. The methodology relies on the application of a composite, potentiostatically-controlled voltage signal which comprises both AC and DC polarization components. Subsequent analysis of the current-time response yields an approximation for the velocity of electroosmotic flow at the microcapiliary tip. Using this methodology, it is also shown, that previously observed low-frequency pseudo-inductive behaviour is related to an accumulation of ions into the capillary tip region under an applied potential via a mechanism based on electroosmosis.