The ability to directly observe membrane potential charging dynamics across a full microscopic field of view is vital for understanding interactions between a biological system and a given electrical stimulus. Accurate empirical knowledge of cell membrane electrodynamics will enable validation of fundamental hypotheses posited by the single shell model, which includes the degree of voltage change across a membrane and cellular sensitivity to external electric field non-uniformity and directionality. To this end, we have developed a high-speed strobe microscopy system with a time resolution of ~ 6 ns that allows us to acquire time-sequential data for temporally repeatable events (non-injurious electrostimulation). The imagery from this system allows for direct comparison of membrane voltage change to both computationally simulated external electric fields and time-dependent membrane charging models. Acquisition of a full microscope field of view enables the selection of data from multiple cell locations experiencing different electrical fields in a single image sequence for analysis. Using this system, more realistic membrane parameters can be estimated from living cells to better inform predictive models. As a proof of concept, we present evidence that within the range of membrane conductivity used in simulation literature, higher values are likely more valid.
Original Publication Citation
Kiester, A. S., Ibey, B. L., Coker, Z. N., Pakhomov, A. G., & Bixler, J. N. (2021). Strobe photography mapping of cell membrane potential with nanosecond resolution. Bioelectrochemistry, 142, 1-10, Article 107929. https://doi.org/10.1016/j.bioelechem.2021.107929
Kiester, Allen S.; Ibey, Bennett L.; Coker, Zachary N.; Pakhomov, Andrei G.; and Bixler, Joel N., "Stobe Photography Mapping of Cell Membrane Potential with Nanosecond Resolution" (2021). Bioelectrics Publications. 314.