Electroporation Is Not Just About Voltage

Electroporation is used to deliver materials such as DNA, RNA, and proteins into cells by applying a short electrical pulse. This pulse temporarily creates pores in the cell membrane, allowing the target materials to enter.

It is often thought that voltage is the most important setting in electroporation, as it controls the pore formation. But it is not the only important factor. Electroporation depends not just on the pulse voltage but also on the pulse width and number, and these parameters should be optimized together.

Balance is more important than one strong setting

Electroporation is about finding the optimal balance.

To achieve high transfection efficiency, sufficient material must enter the cells.

To achieve high viability, sufficient cells should recover and remain viable.

If the condition is too strong, the cells may become stressed and damaged, and it is hard for them to recover. Whereas for weak conditions, not enough pores will be formed so that not much material will enter the cells.

Parameter 1: Voltage - How strong should it be?

Voltage mainly determines the electric field strength applied to the cells.

This affects pore formation in the cell membrane. Depending on cell type (stiffness, thickness, etc.) and material type (structure, size, etc.), the voltage needs to be adjusted.

Higher voltage: may form more and larger pores

Lower voltage: may form fewer and smaller pores

Parameter 2: Pulse width - How long should it be?

Pulse width controls the time of each electrical pulse.

Some materials, because of their size and shape, require a longer time to enter the cells.

Higher pulse width: keeps pores open longer + may increase material entry

Lower pulse width: keeps pores open for a shorter time + may decrease material entry

Parameter 3: Pulse number - How many times should it be?

Pulse number controls the number of electrical pulses applied to cells.

While some cells need a single pulse for pore formation, some require multiple pulses.

Also, some materials may require a stronger force to be pushed inside the cell.

Higher pulse number: may form more pores + more force applied to materials

Lower pulse number: may form fewer pores + less force applied to materials

No single protocol works best for all cell types. Since electroporation results can vary with cell type and conditions, it is important to optimize the protocol to achieve the best outcome.