Table of Contents
Why do we add buffer solution in culture media?
As bacteria grow in their natural habitat or in the laboratory they produce acid as a by produce of their matebolism. This acid by-product often inhibits their growth by changing the surrounding environment. To help prevent this in the laboratory buffers are used.
How do you buffer culture media?
Add the cell culture medium a good buffer such as HEPES (2.55 g/L), and maintain an atmosphere between 5-6% CO2 during incubation step. If you have sodium bicarbonate in the media you need to have the right amount of CO2 to prevent this.
Why are buffers important to cells?
Buffers are essential for living cells. This is because buffers maintain the right pH of a liquid. Since acidic liquids can destroy proteins, and cells are chock-full of proteins, cells need to have buffers inside and outside them in order to protect their protein machines.
Which buffer is used more in tissue culture?
The most commonly used buffer in tissue culture media is the bicarbonate + carbon dioxide buffer but phosphate or tris buffers have also been used.
How pH is maintained in CO2 incubator?
A CO2 incubator is used to culture cells to provide it with the optimum temperature, moisture and to maintain an optimum pH. When the media contains carbonate buffer, the CO2 gas from the cylinder is let into the incubator in such a way that the pH remains constant. You use CO2 in the gas form.
How much HEPES do you add to the media?
HEPES may be added to cell culture media at a final concentration of 10mM to 25 mM to provide additional buffering capacity if required. Lower concentrations are usually not adequate to control fluctuations in pH, and higher concentrations are often toxic.
What are the function of buffers?
The function of a buffer is to keep the pH of a solution within a narrow range.
Why do we place cells in incubator with 5% CO2?
5%CO2 is needed to buffer the system to ensure that the normal physiological pH is maintained for optimum cell growth. CO2 will react with water to form carbonate.
What is the purpose of HEPES?
HEPES : – A biological buffer (exist in a zwitterionic form ). It maintains physiological pH in cell culture when compared to bicarbonate buffers despite the changes in carbon dioxide concentration.
Is HEPES better than Tris?
The pKa of HEPES is 7.5 and the pKa of Tris is 8.1. If you want to maintain the pH at 7.5, HEPES is better than Tris. Because HEPES is a sulfonic acid, you have to add a base to neutralize it, so the solution ends up with a cation, usually Na+.