Electric field-mediated transport of plasmid DNA in tumor interstitium in vivo.

Local pulsed electric field application is a method for improving non-viral gene delivery. Mechanisms of the improvement include electroporation and electrophoresis. To understand how electrophoresis affects pDNA delivery in vivo, we quantified the magnitude of electric field-induced interstitial transport of pDNA in 4T1 and B16.

Electric fields around and within single cells during electroporation-a model study.

One of the key issues in electric field-mediated molecular delivery into cells is how the intracellular field is altered by electroporation. Therefore, we simulated the electric field in both the extracellular and intracellular domains of spherical cells during electroporation. The electroporated membrane was modeled macroscopically by assuming that its electric resistivity was smaller than that of the intact membrane.

Electric fields in tumors exposed to external voltage sources: implication for electric field-mediated drug and gene delivery.

The intratumoral field, which determines the efficiency of electric field-mediated drug and gene delivery, can differ significantly from the applied field. Therefore, we investigated the distribution of the electric field in mouse tumors and tissue phantoms exposed to a large range of electric stimuli, and quantified the resistances of tumor, skin, and electrode-tissue interface. The samples used in the study included 4T1 and B16.

A single molecule detection method for understanding mechanisms of electric field-mediated interstitial transport of genes.

The interstitial space is a rate limiting physiological barrier to non-viral gene delivery. External pulsed electric fields have been proposed to increase DNA transport in the interstitium, thereby improving non-viral gene delivery. In order to characterize and improve the interstitial transport, we developed a reproducible single molecule detection method to observe the electromobility of DNA in a range of pulsed, high field strength electric fields typically used during electric field-mediated gene delivery.

Electric fields within cells as a function of membrane resistivity--a model study.

Externally applied electric fields play an important role in many therapeutic modalities, but the fields they produce inside cells remain largely unknown. This study makes use of a three-dimensional model to determine the electric field that exists in the intracellular domain of a 10-microm spherical cell exposed to an applied field of 100 V/cm. The transmembrane potential resulting from the applied field was also determined and its change was compared to those of the intracellular field.