Limits...
Electroporation Knows No Boundaries: The Use of Electrostimulation for siRNA Delivery in Cells and Tissues.

Luft C, Ketteler R - J Biomol Screen (2015)

Bottom Line: The RNAi technology has emerged as one of the major tools for drug target identification and has been steadily improved to allow gene manipulation in cell lines, tissues, and whole organisms.Some cell types are refractory to high-efficiency transfection with standard methods such as lipofection or calcium phosphate precipitation and require different means.Electroporation is a powerful and versatile method for delivery of RNA, DNA, peptides, and small molecules into cell lines and primary cells, as well as whole tissues and organisms.

View Article: PubMed Central - PubMed

Affiliation: MRC Laboratory for Molecular Cell Biology, University College London, London, UK.

No MeSH data available.


Electroporation of cells. Electroporation occurs through four main steps: (1) polarization of the cell, (2) rapture of the membrane creating nanopores, (3) entry of the macromolecules, and (4) resealing of the membrane. (1) Application of short electrical pulses will result in membrane charging, creating an electrical field and resulting in polarization of the cell. The strong electrical field will result in structural rearrangements of the membrane, creation of water-filled membrane structures (“aqueous pores”) and “nanopores” with a size of more than 1 nm that allow ionic transport. (2) Larger pores are formed in the membrane that allows influx of macromolecules such as DNA or RNA. Generally, more pores are formed at the site facing the negative electrode. (3) Large macromolecules can enter the cell. The negative charge of DNA/RNA can act as a drag to enhance uptake, although, on the other hand, positive ions such as calcium can enhance proximity to the negatively charged membrane prior to uptake. (4) Electroporation is reversible, and once the electric field is switched off, the membrane has the capacity to reseal and keep the macromolecules inside the cell. Resealing occurs on a much longer time frame (minutes to hours), whereas pore formation can occur within milliseconds. Low temperature can enhance resealing, although this may not be practical for eukaryotic cells in some applications.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2 - License 3
getmorefigures.php?uid=PMC4543902&req=5

fig2-1087057115579638: Electroporation of cells. Electroporation occurs through four main steps: (1) polarization of the cell, (2) rapture of the membrane creating nanopores, (3) entry of the macromolecules, and (4) resealing of the membrane. (1) Application of short electrical pulses will result in membrane charging, creating an electrical field and resulting in polarization of the cell. The strong electrical field will result in structural rearrangements of the membrane, creation of water-filled membrane structures (“aqueous pores”) and “nanopores” with a size of more than 1 nm that allow ionic transport. (2) Larger pores are formed in the membrane that allows influx of macromolecules such as DNA or RNA. Generally, more pores are formed at the site facing the negative electrode. (3) Large macromolecules can enter the cell. The negative charge of DNA/RNA can act as a drag to enhance uptake, although, on the other hand, positive ions such as calcium can enhance proximity to the negatively charged membrane prior to uptake. (4) Electroporation is reversible, and once the electric field is switched off, the membrane has the capacity to reseal and keep the macromolecules inside the cell. Resealing occurs on a much longer time frame (minutes to hours), whereas pore formation can occur within milliseconds. Low temperature can enhance resealing, although this may not be practical for eukaryotic cells in some applications.

Mentions: The basis for all electrochemical manipulations of cells is the formation of a polarized cell in an electric field (Fig. 2). This occurs as a consequence of the interaction of an electrical field with charges on the cell surface and interior of the cell. Accordingly, the cellular membrane will impose a restriction on the movement of charges in an electrical field and thus lead to polarization of the cell when placed between two electrodes. This polarization of the cell can result in motions in the cytoplasm leading to structural rearrangements or mechanical fracture. Cell membranes have low polarizability with a dielectric constant of about 2 and low conductivity (~1 nS/cm), whereas the surrounding media have a high dielectric constant (around 80) and high conductivity (about 0.1 S/cm).43 The application of an electrical field will result in high movement of ions in the surrounding media and accumulation at the membrane surface, thus leading to polarization. This in turn will create an electrical field inside the cell that can be of much higher strength than the field in the surrounding media and thus lead to the formation of pores resulting in discharge of the charges at the membrane. The basic relationship to calculate the voltage across a membrane in a spherical object is estimated as


Electroporation Knows No Boundaries: The Use of Electrostimulation for siRNA Delivery in Cells and Tissues.

Luft C, Ketteler R - J Biomol Screen (2015)

Electroporation of cells. Electroporation occurs through four main steps: (1) polarization of the cell, (2) rapture of the membrane creating nanopores, (3) entry of the macromolecules, and (4) resealing of the membrane. (1) Application of short electrical pulses will result in membrane charging, creating an electrical field and resulting in polarization of the cell. The strong electrical field will result in structural rearrangements of the membrane, creation of water-filled membrane structures (“aqueous pores”) and “nanopores” with a size of more than 1 nm that allow ionic transport. (2) Larger pores are formed in the membrane that allows influx of macromolecules such as DNA or RNA. Generally, more pores are formed at the site facing the negative electrode. (3) Large macromolecules can enter the cell. The negative charge of DNA/RNA can act as a drag to enhance uptake, although, on the other hand, positive ions such as calcium can enhance proximity to the negatively charged membrane prior to uptake. (4) Electroporation is reversible, and once the electric field is switched off, the membrane has the capacity to reseal and keep the macromolecules inside the cell. Resealing occurs on a much longer time frame (minutes to hours), whereas pore formation can occur within milliseconds. Low temperature can enhance resealing, although this may not be practical for eukaryotic cells in some applications.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2 - License 3
Show All Figures
getmorefigures.php?uid=PMC4543902&req=5

fig2-1087057115579638: Electroporation of cells. Electroporation occurs through four main steps: (1) polarization of the cell, (2) rapture of the membrane creating nanopores, (3) entry of the macromolecules, and (4) resealing of the membrane. (1) Application of short electrical pulses will result in membrane charging, creating an electrical field and resulting in polarization of the cell. The strong electrical field will result in structural rearrangements of the membrane, creation of water-filled membrane structures (“aqueous pores”) and “nanopores” with a size of more than 1 nm that allow ionic transport. (2) Larger pores are formed in the membrane that allows influx of macromolecules such as DNA or RNA. Generally, more pores are formed at the site facing the negative electrode. (3) Large macromolecules can enter the cell. The negative charge of DNA/RNA can act as a drag to enhance uptake, although, on the other hand, positive ions such as calcium can enhance proximity to the negatively charged membrane prior to uptake. (4) Electroporation is reversible, and once the electric field is switched off, the membrane has the capacity to reseal and keep the macromolecules inside the cell. Resealing occurs on a much longer time frame (minutes to hours), whereas pore formation can occur within milliseconds. Low temperature can enhance resealing, although this may not be practical for eukaryotic cells in some applications.
Mentions: The basis for all electrochemical manipulations of cells is the formation of a polarized cell in an electric field (Fig. 2). This occurs as a consequence of the interaction of an electrical field with charges on the cell surface and interior of the cell. Accordingly, the cellular membrane will impose a restriction on the movement of charges in an electrical field and thus lead to polarization of the cell when placed between two electrodes. This polarization of the cell can result in motions in the cytoplasm leading to structural rearrangements or mechanical fracture. Cell membranes have low polarizability with a dielectric constant of about 2 and low conductivity (~1 nS/cm), whereas the surrounding media have a high dielectric constant (around 80) and high conductivity (about 0.1 S/cm).43 The application of an electrical field will result in high movement of ions in the surrounding media and accumulation at the membrane surface, thus leading to polarization. This in turn will create an electrical field inside the cell that can be of much higher strength than the field in the surrounding media and thus lead to the formation of pores resulting in discharge of the charges at the membrane. The basic relationship to calculate the voltage across a membrane in a spherical object is estimated as

Bottom Line: The RNAi technology has emerged as one of the major tools for drug target identification and has been steadily improved to allow gene manipulation in cell lines, tissues, and whole organisms.Some cell types are refractory to high-efficiency transfection with standard methods such as lipofection or calcium phosphate precipitation and require different means.Electroporation is a powerful and versatile method for delivery of RNA, DNA, peptides, and small molecules into cell lines and primary cells, as well as whole tissues and organisms.

View Article: PubMed Central - PubMed

Affiliation: MRC Laboratory for Molecular Cell Biology, University College London, London, UK.

No MeSH data available.