Single-step electrical field strength screening to determine electroporation induced transmembrane transport parameters

Abstract

The design of effective electroporation protocols for molecular delivery applications requires the determination of transport parameters including diffusion coefficient, membrane resealing, and critical electric field strength for electroporation. The use of existing technologies to determine these parameters is time-consuming and labor-intensive, and often results in large inconsistencies in parameter estimation due to variations in the protocols and setups. In this work, we suggest using a set of concentric electrodes to screen a full range of electric field strengths in a single test to determine the electroporation-induced transmembrane transport parameters. Using Calcein as a fluorescent probe, we developed analytical methodology to determine the transport parameters based on the electroporation-induced pattern of fluorescence loss from cells. A monolayer of normal human dermal fibroblast (NHDF) cells were pre-loaded with Calcein and electroporated with an applied voltage of 750 V with 10 and 50 square pulses with 50 μs duration. Using our analytical model, the critical electric field strength for electroporation was found for the 10 and 50 pulses experiments. An inverse correlation between the field strength and the molecular transport time decay constant, and a direct correlation between field strength and the membrane permeability were observed. The results of this work can simplify the development of electroporation-assisted technologies for research and therapies.

Membrane permeabilization of mammalian cells using bursts of high magnetic field pulses

“…The non-homogeneous sample conductivity could be addressed by applying, high-frequency bipolar pulse protocols (H-FIRE) which mitigate the impedance differences ( Bhonsle et al, 2015 ; Sano et al, 2015 ) but unfortunately require delivery of higher energy than longer unipolar irreversible electroporation (IRE) pulses ( Murovec et al, 2016 ; Sweeney et al, 2016 ). However, universal protocols, which allow countering or optimising all the limitations described above, are still not available ( Pakhomova et al, 2011 ; Blumrosen et al, 2016 ; Yildirim et al, 2016 ).…”

A predictive model for personalization of nanotechnology-based phototherapy in cancer treatment

“…We model the probability of cell death after treatment as p D , which can be estimated as a function of the experimental conditions. The cell death rate associated with a particular experimental setup can be measured based on the fluorescent intensity of the cells present in the training data, as this variable attests to the cells' condition (43,44). Specifically, a signal indicating high fluorescent intensity can be taken to indicate reduced cell viability, since it means that membrane permeability is greater and consequently the cell has a higher probability of dying.…”

Electroporation-based proteome sampling ex vivo enables the detection of brain melanoma protein signatures in a location proximate to visible tumor margins

“…We also showed ex vivo that electroporation-based molecular harvesting extracts proteome with tissue-specific signatures for liver [ 23 ]. In the previous work in vitro , we showed that electroporation enables molecular transport out of the cells up to 3.9mm around the electrode [ 34 ]. Here we demonstrate the ability to gather the ex vivo extracted molecules for the diagnostics.…”