Extraction of geometric and transport parameters from the time constant of exocytosis transients measured by nanoscale electrodes

TL;DR

This paper develops analytical models and simulations to extract geometric and transport parameters from exocytosis transients measured by nanoscale electrodes, enhancing understanding of vesicle release dynamics.

Contribution

It introduces physics-based scaling laws for decay time constants in VIEC, enabling parameter extraction and improved analysis of exocytosis events.

Findings

Power law dependence of decay time on geometric and transport parameters

Models agree well with simulations and literature data

Potential for advanced parameter extraction strategies

Abstract

Exocytosis is a fundamental process related to the information exchange in the nervous and endocrine system. Among the various techniques, vesicle impact electrochemical cytometry (VIEC) has emerged as an effective method to mimic the exocytosis process and measure dynamic information about content transfer using nanoscale electrodes. In this manuscript, through analytical models and large scale simulations, we develop scaling laws for the decay time constant ($\tau$) for VIEC single-exponential transients. Specifically, our results anticipate a power law dependence of $\tau$ on the geometric and the transport parameters. This model compares very well with large scale simulations exploring the parameter space relevant for VIEC and with experimental results from literature. Remarkably, such physics based compact models could allow for novel multi-feature based self consistent strategies for back extraction of geometric and transport parameters and hence could contribute towards better statistical analysis and understanding of exocytosis transients and events.