Tris-Buffered Saline
Encyclopedia
Tris-buffered saline is a buffer used in some biochemical
techniques to maintain the pH
within a relatively narrow range. Tris (with HCl) has a slightly alkaline buffering capacity in the 7–9.2 range.
Tris
has a pKa of 8.06 at 25 °C. The pKa declines approximately 0.03 units per degree Celsius rise in temperature. This can lead to relatively dramatic pH shifts when there are shifts in solution temperature.
Adjust pH with HCl to pH 7.6.
The simplest way to prepare a TBS solution is to use TBS tablets. They are formulated to give a ready to use TBS solution upon dissolution in 500 ml of deionized water.
Note that concentration of tris and NaCl as well as the pH can vary, and the resulting solution would still be referred to as "TBS". Tris concentration (giving buffering capacity) can vary from 10 to 100 mM. As TBS is used to emulate physiological conditions (as in animal or human body), the pH value is slightly alkaline, ranging from 7.4 to 8.0. NaCl gives the isotonic (mostly used 150 mM NaCl corresponds to physiological conditions: 0.9% NaCl) or hypertonic (500mM NaCl) salt concentration. Additionally Tween 20 can also be added in order to use it as wash solution in immunoassays or to block. (TTBS or TBST
)
TBS-tween tablets are also available.
In the preparation of gels for western blotting, the lower gel contains tris with a pH of 8.8 and the upper gel contains Tris with a pH of 6.8
Biochemistry
Biochemistry, sometimes called biological chemistry, is the study of chemical processes in living organisms, including, but not limited to, living matter. Biochemistry governs all living organisms and living processes...
techniques to maintain the pH
PH
In chemistry, pH is a measure of the acidity or basicity of an aqueous solution. Pure water is said to be neutral, with a pH close to 7.0 at . Solutions with a pH less than 7 are said to be acidic and solutions with a pH greater than 7 are basic or alkaline...
within a relatively narrow range. Tris (with HCl) has a slightly alkaline buffering capacity in the 7–9.2 range.
Tris
Tris
Tris is an abbreviation of the organic compound known as trisaminomethane, with the formula 3CNH2. Tris is extensively used in biochemistry and molecular biology. In biochemistry, tris is widely used as a component of buffer solutions, such as in TAE and TBE buffer, especially for solutions of...
has a pKa of 8.06 at 25 °C. The pKa declines approximately 0.03 units per degree Celsius rise in temperature. This can lead to relatively dramatic pH shifts when there are shifts in solution temperature.
Applications
TBS has many uses because it is isotonic and non-toxic. It can be used to dilute substances. Additives can be used to add function.Contents of TBS
The following is a sample recipe for TBS:- 50 mM trisTrisTris is an abbreviation of the organic compound known as trisaminomethane, with the formula 3CNH2. Tris is extensively used in biochemistry and molecular biology. In biochemistry, tris is widely used as a component of buffer solutions, such as in TAE and TBE buffer, especially for solutions of...
- 150 mM NaCl
Adjust pH with HCl to pH 7.6.
The simplest way to prepare a TBS solution is to use TBS tablets. They are formulated to give a ready to use TBS solution upon dissolution in 500 ml of deionized water.
Note that concentration of tris and NaCl as well as the pH can vary, and the resulting solution would still be referred to as "TBS". Tris concentration (giving buffering capacity) can vary from 10 to 100 mM. As TBS is used to emulate physiological conditions (as in animal or human body), the pH value is slightly alkaline, ranging from 7.4 to 8.0. NaCl gives the isotonic (mostly used 150 mM NaCl corresponds to physiological conditions: 0.9% NaCl) or hypertonic (500mM NaCl) salt concentration. Additionally Tween 20 can also be added in order to use it as wash solution in immunoassays or to block. (TTBS or TBST
TBST
TBST is mixture of Tris-Buffered Saline and Tween 20. It is a buffer used for washing nitrocellulose membrane in western blotting and microtiter plate wells in ELISA assays.-Contents of TBS-Tween:The following is a sample recipe for TBST:...
)
TBS-tween tablets are also available.
In the preparation of gels for western blotting, the lower gel contains tris with a pH of 8.8 and the upper gel contains Tris with a pH of 6.8