Why is DNA extraction important

DNA isolation from tomatoes

What is behind it:

Detergent breaks open the cell envelope

In a first step, the DNA has to be freed from the cell nucleus. The mortar tears the cells apart and partially breaks them open. With the detergent and the acid of the lemon, the cell and nuclear envelope is now dissolved. This is done as follows: The washing-up liquid is a so-called detergent, i.e. a substance that dissolves fats. Since the shell of the cell and the nucleus consists of fats, it dissolves in the detergent. The acidity of the lemon increases the solubility of the fats.

DNA is soluble in water

Water particles are not charged, but they have polarity. This means that within the water particle there is one side that is more positively charged and another side that is more negatively charged. This polarity allows the more positive side of the water to attach to the negatively charged DNA and thus make it soluble. It can easily flow through the coffee filter. The salt concentration in the extraction buffer corresponds roughly to the conditions in the living organism, i.e. a physiological saline solution.

Nebulas are used to form balls of DNA

Nitrogen does not have the same polarity as water. If you add methylated spirits to the mixture of water and cell components, the DNA becomes insoluble, begins to clump and becomes visible as a white tangle.

Source: Interpharma

Images: SimplyScience.ch

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