Tris has a pKa of 8.07 at 25 °C, which implies that the buffer has an effective pH range between 7.07 and 9.07.
The pKa declines approximately 0.03 units per degree Celsius rise in temperature.
Silver-containing single-junction pH electrodes (e.g., silver chloride electrode) are incompatible with Tris (Ag-tris precipitation clogs the junction). Double-junction electrodes are resistant to this problem, and non-silver containing electrodes are immune.
Making buffer solutions by neutralizing TrisHCl requires attention to the attendant changes in ionic strength.
Tris inhibits a number of enzymes, and therefore it should be used with care when studying proteins.
Tris is prepared industrially in two steps from nitromethane via the intermediate (HOCH2)3CNO2. Reduction of the latter gives tris(hydroxymethyl)aminomethane.
The useful buffer range for tris (7-9) coincides with the physiological pH typical of most living organisms. This, and its low cost, make tris one of the most common buffers in the biology/biochemistry laboratory. Tris is also used as a primary standard to standardize acid solutions for chemical analysis.
Tris is used to increase membrane permeability of cell membranes.
^El-Harakany, A.A.; Abdel Halima, F.M. and Barakat, A.O. (1984). "Dissociation constants and related thermodynamic quantities of the protonated acid form of tris-(hydroxymethyl)-aminomethane in mixtures of 2-methoxyethanol and water at different temperatures". J. Electroanal. Chem.162 (1–2): 285–305. doi:10.1016/S0022-0728(84)80171-0.Cite uses deprecated parameters (help)
^Vega, C.A.; Butler, R.A. et al. (1985). "Thermodynamics of the Dissociation of Protonated Tris(hydroxymethy1)aminomethane in 25 and 50 wt % 2-Propanol from 5 to 45 °C". J. Chem. Eng. Data30 (4): 376–379. doi:10.1021/je00042a003.
^Desmarais, WT; et al. (2002). "The 1.20 Å resolution crystal structure of the aminopeptidase from Aeromonas proteolytica complexed with Tris: A tale of buffer inhibition". Structure10 (8): 1063–1072. doi:10.1016/S0969-2126(02)00810-9. PMID12176384.
^Ghalanbor, Z; et al. (2008). "Binding of Tris to Bacillus licheniformis alpha-amylase can affect its starch hydrolysis activity". Protein Peptide Lett.15 (2): 212–214. doi:10.2174/092986608783489616. PMID18289113.
^Irvin, R.T.; MacAlister, T.J.; Costerton, J.W. (1981). "Tris(hydroxymethyl)aminomethane Buffer Modification of Escherichia coli Outer Membrane Permeability". J. Bacteriol145 (3): 1397–1403.
^Kallet, RH; Jasmer RM, Luce JM et al. (2000). "The treatment of acidosis in acute lung injury with tris-hydroxymethyl aminomethane (THAM)". American Journal of Respiratory and Critical Care Medicine161 (4): 1149–1153. doi:10.1164/ajrccm.161.4.9906031. PMID10764304.Cite uses deprecated parameters (help)