"Traube Cell" experiment
How to grow an artificial cell
Biology and chemistry are closely connected, and in this enlightening experiment we will learn to create artificial cells by a chemical reaction.
Reagents and equipment:
- 5% copper sulfate solution;
- potassium ferrocyanide tablets;
- distilled water;
Dissolve 50 g of copper sulfate in 950 g of distilled water. Pour the solution into the cuvette. Add several tablets of potassium ferrocyanide.
Semi-permeability is the ability to pass certain substances through a membrane selectively. Membranes of plant cells have this property, for example. In the interaction of potassium ferrocyanide with copper sulfate, copper hexacyanoferrate (II) forms, which has properties of semi-permeability. This was established by the German physicist and physiologist Moritz Traube. His work showed that it was possible to find chemical compounds which on interaction became completely similar to a plant cell,capable of taking some substances from the environment and secreting others:
2CuSO₄ + K₄[Fe(CN)₆] → Cu₂[Fe(CN)₆] + 2K₂SO₄
The concentration of potassium ferrocyanate inside the cell is greater than the concentration of copper sulfate outside it, and so water starts to enter the cell, thus expanding it until the concentrations of potassium ferrocyanate and copper sulfate become equal. The growth of the Traube cell takes place unevenly, as the membrane of copper hexacyanoferrate (II) gradually breaks from pressure, and in the place of the break the copper sulfate and potassium ferrocyanate interact once more, and a film forms again.
Wear protective gloves and glasses during the experiment.
Warning! Only under professional supervision.