Electroporation Cuvettes, 0.2 cm - FAQs

Will Invitrogen cuvettes fit my electroporator?

Our cuvettes are known as the "Potter-style" cuvettes, and they fit most electroporators that accept a standard size cuvette.

How can I avoid arcing during electroporation of E. coli?

When electroporating cells at high voltage in conductive buffers, arcing may occur. MgCl₂ and PO₄ in particular are very conductive.

Some suggestions:

1) Keep ionic strength of cloning reactions to a minimum. If reaction buffers contain high salt, dilute DNA sample in water or TE buffer before electroporation.

2) Minimize addition of conductive ions. The volume of DNA solution should not exceed 5% of the total reaction. Example: 2 ?l DNA per 40 ?l of cells.

3) Be sure no air bubbles are present.

4) Make sure the electrical contacts are clean and tight. Wipe away any condensation on the outside of the cuvette.

5) For best results, the cells should be aliquoted into the bottom of the gap - tap the cuvette gently to help the cells settle to the bottom.

What is meant by "field strength" (kV/cm) when determining settings for electroporation? What are typical settings for different cell types?

The two most important electrical parameters for consideration in electroporation are pulse length and field strength. Field strength is defined as volts/centimeter, where V is equal to the initial peak voltage and cm is equal to the measurement of the gap between the electrodes of the cuvette in centimeters. For example, during electroporation of bacteria at 1,500 Volts in a 0.1 cm cuvette, the field strength would be 15,000 volts/cm, or 15 kV/cm. Typically, electroporation of bacteria requires field strengths of greater than 15 kV/cm. Yeast cells require 6-8 kV/cm, and mammalian cells often require optimization between 0.5 to 2.5 kV/cm.

What are recommended settings for bacterial electroporation of 80 ul cells in 0.2 cm cuvettes? What is the maximum cell volume to use in a 0.2 cm cuvette?

Depending upon the manufacturer of the electroporator, the settings may range in value (25 -50 ?F, 100-200 ohms, 1500-2500 volts). Follow the manufacturer's recommended settings for bacterial electroporation. The maximum recommended cell volume that should be used for a 0.2 cm cuvette without compromising efficiency is 160 ?l.