Tris

From OpenWetWare

(Difference between revisions)
Jump to: navigation, search
Current revision (13:17, 14 October 2008) (view source)
m (See also)
 
(8 intermediate revisions not shown.)
Line 1: Line 1:
-
Tris is a common buffering agent and is short for tris[hydroxymethyl]aminomethane (C<sub>4</sub>H<sub>11</sub>NO<sub>3</sub>).
+
[[Image:160px-Tris.png|thumb|Chemical structure of Tris - 2-Amino-2-hydroxymethyl-propane-1,3-diol]]
 +
 
 +
[http://en.wikipedia.org/wiki/Tris Tris] is a common buffering agent and is short for tris[hydroxymethyl]aminomethane (C<sub>4</sub>H<sub>11</sub>NO<sub>3</sub>, 2-Amino-2-hydroxymethyl-propane-1,3-diol).
* The formula weight is 121.14
* The formula weight is 121.14
* The pKa of Tris is 8.3
* The pKa of Tris is 8.3
* dpK<sub>a</sub>/dT is -.028
* dpK<sub>a</sub>/dT is -.028
-
* A buffer at pH 6.8 at 25C will have a pH of 6.46 at 37C
+
* A buffer at pH 6.8 at 25&deg;C will have a pH of 6.46 at 37&deg;C
** Note that adding HCl during titration will affect the temperature of the solution
** Note that adding HCl during titration will affect the temperature of the solution
* Dilution by a factor of 10 will reduce the pH by 0.1 pH units.
* Dilution by a factor of 10 will reduce the pH by 0.1 pH units.
 +
 +
== Preparing a 1M Tris, pH 7.4 solution, from [http://biologicalworld.com/trisbuffer.htm biologicalworld] ==
 +
* Weigh 121.1 g Tris in 700 ml double distilled water
 +
* Do not start with too much water; otherwise, the volume after pHing may be too great
 +
* Start stirring, and then check the pH
 +
* With a 3M HCl solution, start to pH the solution such that the pH reaches 7.4
 +
(Be careful not to inhale the HCl.)
 +
* Add with double distilled water up to 1L
 +
* Filter or autoclave if necessary
 +
* May be better to store at 4 degrees C
 +
* Dilute to appropriate concentration for use in biochemistry or molecular biology experiments.  20 mM or 50 mM Tris, pH 7.4 solutions are common.
 +
 +
== Stability ==
 +
* 18 months for Tris-HCl buffer according to this data sheet [http://www.labvision.com/pdf/uvdatasheet/AP-9005-XXX.pdf]
 +
* 2 years for Tris-EDTA according to this data sheet [http://www.labtech.co.uk/downloads/biothema/21-500.pdf]
 +
 +
== See also ==
 +
* [[TBS]] - tris-buffered saline
 +
* [[TBST]] - tris-buffered saline with Tween
 +
 +
[[Category:Material]]
 +
[[Category:Buffers]]

Current revision

Chemical structure of Tris - 2-Amino-2-hydroxymethyl-propane-1,3-diol
Chemical structure of Tris - 2-Amino-2-hydroxymethyl-propane-1,3-diol

Tris is a common buffering agent and is short for tris[hydroxymethyl]aminomethane (C4H11NO3, 2-Amino-2-hydroxymethyl-propane-1,3-diol).

  • The formula weight is 121.14
  • The pKa of Tris is 8.3
  • dpKa/dT is -.028
  • A buffer at pH 6.8 at 25°C will have a pH of 6.46 at 37°C
    • Note that adding HCl during titration will affect the temperature of the solution
  • Dilution by a factor of 10 will reduce the pH by 0.1 pH units.

Preparing a 1M Tris, pH 7.4 solution, from biologicalworld

  • Weigh 121.1 g Tris in 700 ml double distilled water
  • Do not start with too much water; otherwise, the volume after pHing may be too great
  • Start stirring, and then check the pH
  • With a 3M HCl solution, start to pH the solution such that the pH reaches 7.4

(Be careful not to inhale the HCl.)

  • Add with double distilled water up to 1L
  • Filter or autoclave if necessary
  • May be better to store at 4 degrees C
  • Dilute to appropriate concentration for use in biochemistry or molecular biology experiments. 20 mM or 50 mM Tris, pH 7.4 solutions are common.

Stability

  • 18 months for Tris-HCl buffer according to this data sheet [1]
  • 2 years for Tris-EDTA according to this data sheet [2]

See also

  • TBS - tris-buffered saline
  • TBST - tris-buffered saline with Tween
Personal tools