Description
TAPS is a zwitterionic buffering agent used in biochemistry and molecular biology. It is part of the Tris family of buffers and is useful for a pH range of 7.7 – 9.1. The members of TRIS family are tris(hydroxymethyl)aminomethane (TRIS), N-[tris(hydroxymethyl)methyl]-2-aminoethanesulfonic acid (TES), N-[tris(hydroxymethyl)methyl]-3-aminopropanesulfonic acid (TAPS), N-[tris(hydroxymethyl)methyl]-3-amino-2-hydroxypropanesulfonic acid (TAPSO), and N-tris(hydroxymethyl)methyl-4-aminobutanesulfonic acid (TABS) buffers[1]. The solubilities of TAPS in aqueous solution decrease with increasing concentration of the salts (salting-out effect)[2]. TAPS is the preferred culture media buffer used for dinoflagellate experiments, allowing for minimal pH change and maximal growth. It is also often used in capillary electrophoresis to analyze DNA and in planar chromatography to separate dyes. TAPS may form a complex with some common metals so stability constants and concentrations should be taken into account when choosing this buffer. TAPS is capable of inhibiting connexin channels in animal cells.
Chemical Properties
White/clear crystalline powder
Uses
A zwitterionic Good's Buffer
Definition
ChEBI: N-[tris(hydroxymethyl)methyl]-3-aminopropanesulfonic acid is an organosulfonic acid.
Application
TAPS is a zwitterionic buffer used in biochemistry and molecular biology. It has a useful pH range of 7.7 - 9.1. TAPS has been utilized in capillary electrophoresis of DNA and DNA-dye complexes. Dyes can be separated by planar chromatography with electroosmotic flow containing 1 mM TAPS in the mobile phase. The stability constants of metal ions with TAPS have been investigated through the use of capillary electrophoresis. TAPS has also been shown to inhibit the activity of connexin channels. The activity of various carbonic anhydrases has been studied using TAPS physiological buffer, pKa = 8.4 at 20° C.
References
[1] Gupta B, et al. Stability Constants for the Equilibrium Models of Iron(III) with Several Biological Buffers in Aqueous Solutions. Journal of Solution Chemistry, 2013; 42: 2296–2309.
[2] Taha M, et al. New Insights into Buffer-Ionic Salt Interactions: Solubilities, Transfer Gibbs Energies, and Transfer Molar Volumes of TAPS and TAPSO from Water to Aqueous Electrolyte Solutions. Journal of Solution Chemistry, 2010; 39: 1665–1680.
