@article {141, title = {Comparison of the effects of the repetition rate between microsecond and nanosecond pulses: Electropermeabilization-induced electro-desensitization?}, journal = {Biochimica et Biophysica Acta (BBA) - General Subjects}, volume = {1840}, year = {2014}, pages = {2139 - 2151}, keywords = {Electroporation}, issn = {0304-4165}, doi = {http://dx.doi.org/10.1016/j.bbagen.2014.02.011}, url = {http://www.sciencedirect.com/science/article/pii/S0304416514000725}, author = {Aude Silve and A. Guimer{\`a} Brunet and B. Al-Sakere and Antoni Ivorra and L.M. Mir} } @conference {Silve2011, title = {{Detection of permeabilisation obtained by micropulses and nanopulses by means of bioimpedance of biological tissues}}, booktitle = {5th European Conference on Antennas and Propagation (EUCAP)}, year = {2011}, pages = {3164{\textendash}3167. {\textcopyright} 2011 Institute of Electrical and Electronics Engineers, Inc.}, address = {Rome, Italy}, abstract = {

In this paper permeabilisation of potato tissue caused by either microsecond electric pulses or nanosecond electric pulses is compared. The intensity of permeabilisation is quantified by means of bio-impedance change. Thanks to this method, the impact of the repetition frequency was investigated. Data show that very low repetition frequencies can be much more efficient to permeabilise.

}, author = {Aude Silve and Antoni Ivorra and L.M. Mir} } @article {Ivorra2010a, title = {{Electric field redistribution during tissue electroporation: its potential impact on treatment planning}}, journal = {Comptes Rendus Physique}, volume = {Accepted (still pending publication)}, year = {2010}, abstract = {
Electroporation is the phenomenon in which cell membrane permeability is increased by exposing the cell to short high electric field pulses. Electroporation is accompanied by an increase of tissue electrical conductivity during the pulses. Such conductivity increase results in a redistribution of the electric field magnitude that can be simulated with simple functions describing the change in tissue conductivity. Experiments on potato tuber reveal that the conductivity increase phenomenon has indeed a significant impact on field distribution, and validate the use of models that take into account such conductivity alteration. For instance, the error in electroporated area estimation can decrease from 30 \% to 3 \%.\ 
}, author = {Antoni Ivorra and Boris Rubinsky and L.M. Mir} } @article {Ivorra2010, title = {{Electrical modeling of the influence of medium conductivity on electroporation.}}, journal = {Physical chemistry chemical physics : PCCP}, volume = {12}, number = {34}, year = {2010}, pages = {10055{\textendash}64}, abstract = {

Electroporation is the phenomenon in which cell membrane permeability is increased by exposing the cell to short high electric field pulses. Experimental data show that the amount of permeabilization depends on the conductivity of the extracellular medium. If medium conductivity decreases then it is necessary to deliver a pulse of larger field amplitude in order to achieve the same effect. Models that do not take into account the permeabilization effect on the membrane conductivity cannot reproduce qualitatively the experimental observations. Here we employ an exponential function for describing the strong dependence of membrane conductivity on transmembrane potential. Combining that model with numerical methods we demonstrate that the dependence on medium conductivity can be explained as being the result of increased membrane conductance due to electroporation. As experimentally observed, extracellular conductivities of about 1 and 0.1 S m(-1) yield very similar results, however, for lower conductivities (\<0.01 S m(-1)) the model predicts that significantly higher field magnitudes will be required to achieve the same amount of permeabilization.

}, keywords = {Biological, Cell Membrane, Cell Membrane Permeability, Cell Membrane: metabolism, Diffusion, Electric Conductivity, Electroporation, Membrane Potentials, Models, Reproducibility of Results}, issn = {1463-9084}, doi = {10.1039/c004419a}, url = {http://www.ncbi.nlm.nih.gov/pubmed/20585676}, author = {Antoni Ivorra and J. Villemejane and L.M. Mir} } @inbook {Silve2010, title = {{Nanosecond pulsed electric field delivery to biological samples: difficulties and potential solutions}}, booktitle = {Advanced Electroporation Techniques in Biology and Medicine}, year = {2010}, pages = {353{\textendash}370}, abstract = {

In this chapter we discuss particular features of the nanosecond electric pulsed fields (nsPEFs) that must be taken into account when experimenting on their delivery to biological samples. The purpose of the chapter is to provide future users of this technology with some advice on how to correctly apply it. It is first analyzed how propagation related phenomena can impact on the actual electric field pulse that is applied to the sample. In particular, it is shown that impedance matching for the exposure chamber will be a key element. It is then proposed to employ monitoring systems for voltage and current signals and some indications about their use and limitations are given. Finally, the electrochemical and thermal consequences of nsPEFs delivery are also discussed. We conclude that only excellent experimental conditions can result in robust, controlled and reproducible data on the nsPEFs biological effects.

}, keywords = {breakdown of dielectric, electrochemical reactions, impedance, matching, materials, monitoring, nanosecond electric pulses, thermal effects, transmission line, waves propagation}, isbn = {978-1-439-81906-7}, author = {Aude Silve and J. Villemejane and Joubert, V. and Antoni Ivorra and L.M. Mir} }