Microinjection allows for the efficient transfer of controlled nucleotide amounts into the nucleus of a specific target cell. It is a very precise, but time-consuming and expensive transfection method with a very low throughput only. Microinjection is mostly used for special applications, such as single cell manipulation or the generation of transgenic animals, e.g., by pronuclear injection in mice.
Principle:
With this physical method, the target cell is positioned under a microscope and being fixed by a pipette. The nucleotide solution is then directly injected into the cytoplasm and/or the nucleus using a fine glass capillary needle. This precise procedure demands a rather expensive microinjection system and a lot of skill and practice. Once within the nucleus, the nucleotide can immediately integrate into the endogenous DNA. Given these prerequisites, microinjection is highly effective and offers the transfer of precisely controlled nucleotide amounts. However, as each single cell needs to be microinjected individually, this method is very time-consuming.
ibidi Solutions:
- ibidi provides specialized µ-Dishes with low walls, which have been designed to give easy access to the target cells for microinjection. The μ-Dish 35 mm, low enables exact positioning of micromanipulators for a precise injection process. Further, their excellent optical quality allows for high-quality visualization during microinjection.
Electroporation allows for the transient and stable transfection of any cell type. This method is easy and reliable, but it requires high cell numbers due to high rates of cell death during the procedure. Therefore, electroporation is not suitable for sensitive and difficult-to-culture cell types, such as primary cells. Further, a special, expensive electroporation device is required.
Principle:
During electroporation, a mixture of the cells and the nucleotide of interest is exposed to an intense electric field. This leads to transient cell membrane destabilization, making the cell membrane permeable to the nucleotides that are present in the surrounding solution. The cell membrane is transiently permeabilized by a short electric pulse, allowing the nucleotides, which are present in the surrounding solution, to enter the cytoplasm. After removing the electric field, the cell membrane stabilizes, enclosing the nucleotides in the cytoplasm, where they are expressed.
Read on and learn more about Chemical Transfection or Viral Transduction.