Hydroxymethyl aminomethane

H0CH3)3CNHH3 121.137 Tris(hydroxymethyl)aminomethane is available commercially as a primary standard. Dry at 100-103°C (<110°C). In titrations with a strong acid the equivalence point is at about pH 4.5-5. Equivalent weight is the formula weight. [J. H. Eossum, P. C. Markunas, and J. A. Riddick, Anal. Chem., 23 491 (1951).]... 

The end point for this titration is improved by titrating to the second equivalence point, boiling the solution to expel CO2, and retitrating to the second equivalence point. In this case the reaction is Na2C03 + 2H3O+ -> CO2 + 2Na+ + 3H2O TRIS stands for tr/s-(hydroxymethyl)aminomethane. 

AB, AEFD and TRIS AMINO are registered trademarks of ANGUS Chemical Company. Common name is tris(hydroxymethyl)aminomethane. 

Fig. 3. (a) Reaction of pytidoxal 5 -phosphate (PLP) witii an amino-temiinal amino group of hemoglobin (Hb). The reagent is in the form of a Schiff s base with tris(hydroxymethyl)aminomethane [77-86-1] (Tris) buffet, and the reaction is a transamination, (b) The resulting unstable Schiff s base is reduced with... 

AACC Method32-07for TDF, SDF, and IDF. This approved method is a modification of the Prosky method. The phosphate buffer is replaced by a buffer of 2(A[-morpholino)ethanesulfonic acid (MES) [4432-31-9] and tris(hydroxymethyl)aminomethane (TRIS) [77-86-1]. Precision is improved and analysis time is reduced. I DE may be determined on a separate sample or calculated by summing the SDE and IDE values. The MES /TRIS-modified method has received final approval by AACC and official first action by AO AC (5). 

Heavy metal contamination of pH buffers can be removed by passage of the solutions through a Chelex X-100 column. For example when a solution of 0.02M HEPES [4-(2-HydroxyEthyl)Piperazine-l-Ethanesulfonic acid] containing 0.2M KCl (IL, pH 7.5) alone or with calmodulin, is passed through a column of Chelex X-100 (60g) in the K" " form, the level of Ca ions falls to less than 2 x 10" M as shown by atomic absorption spectroscopy. Such solutions should be stored in polyethylene containers that have been washed with boiling deionised water (5min) and rinsed several times with deionised water. TES [, N,N, -Tetraethylsulfamide] and TRIS [Tris-(hydroxymethyl)aminomethane] have been similarly decontaminated from metal ions. 

These same dependencies will, in general, apply to the heat of ionization of the buffer acid, AH. Thermodynamic quantities, namely, AH°, have been reported for some buffer substances, and it is found that A//° is temperature dependent. Bates and Hetzer studied the temperature dependence of for the important buffer tris(hydroxymethyl)aminomethane (TRIS), finding... 

FIGURE 3 Effect of the amount of cholesterol on the particle size. Phosphatidylcholine/cholesterol liposomes were prepared by the octyl glucoside dilution technique. The begin concentration of the mixed micelles was 150 mM octyl glucoside and 10 mM phosphatidylcholine in 10 mM tris(hydroxymethyl)aminomethane and 0.9% NaCl, pH 7.4. Dilution was performed with an automatic titration unit at a dilution rate (= dilution factor, relative to the initial volume, per unit of time) of 0.026 sec"l ( a and ) or 0.69 sec l ( and o). Mean diameters after dilution and ) and after filtration ( L and q) are repi sented. (Adapted from Jiskoot et al, 1986a.)... 

Tris-hydroxymethyl-aminomethane (THAM) has been evaluated in ischemic stroke to reduce mass effect and ICP. It acts as a bulfer, neutralizing acidosis on a local level, including in the brain parenchyma. It has been studied in animal models of stroke, showing an effect in reducing the size of and swelling from cerebral infarction. To date, however, THAM has not been studied in a controlled fashion in humans with ischemic stroke. 

FIGURE 5.7 Second-order hyperfine shift in the X-band EPR of the Cu(II)-Tris complex. The thin solid line is the experimental spectrum of 1.5 mM CuS04 in 200 mM Tris-HCl buffer, pH 8.0 taken at v = 9420 MHz and T = 61 K. Tris is tris-(hydroxymethyl)aminomethane or 2-amino-2-hydroxymethyl-l,3-propanediol. The broken lines are simulations using the parameters g = 2.047, gN = 2.228, Atl = 185 gauss. In the lower trace the second-order correction has been omitted. 

TEP TL TLC TMB TMP TMP TMPG TNS TPB TRIS TRITC TTAB UA USDA-FSIS Triethylphosphine Total luminescence Thin layer chromatography T etramethylbenzidine 2,4,6,8-Tetrathiomorpholinopyrimido [5,4-d] pyrimidine Trimethylphosphine S S -Trimethoxyphenylglyoxal Potassium 2-p-toluidinylnaphthalene-6-sulfonate Tetradecylpyridine bromide Tris (hydroxymethyl) aminomethane Tetramethylrhodamine isothiocyanate Tetradecyltrimethyl ammonium bromide Uric acid U.S. Department of Agriculture-Food Safety and Inspection Service... 

A series of amphiphiles containing a polygalactosylated tris(hydroxymethyl) aminomethane (Tris) linked to a diacyl aspartic acid (31) were synthesized by Polidori and co-workers.88 These compounds had a peptidic spacer for control of the hydrophilic/lipophilic balance as well as providing intermolecu-lar hydrogen bonding. The mono- and digalactosylated (31a, 31b) derivatives... 

The preformed (BC) method is a one-step process used in this case to introduce high multiplicity of terminal hydroxy groups. The method involves direct coupling of branch cell reagents (i.e. tris(hydroxymethyl)aminomethane (Tris-)) by amidation of ester terminated PAMAM dendrimers. Advancement to the next generation of branch cells occurs in one step. 

The standard calorimetric reaction of tris(hydroxymethyl) aminomethane (THAM) neutralization with HC1 was used in several initial experiments to determine both precision and accuracy for the data acquisition and reduction process. Three to five minutes were allowed between acid additions, since this same time frame was used for all later suspension titrations in order to minimize the effects of slow surface reactions which occur during a titration (9,29,30). The amount of acid added in each experiment was varied to generate heat changes of 40-400 mj (typical heat changes observed in our adsorption studies with goethite suspensions). 

An ethanolic solution of 3H-Flunisolide is diluted with tris-(hydroxymethyl)-aminomethane/hydro-chloric acid buffer and 0.1% gelatin such that 0.1 ml portion contains 8,000 to 10,000 cmp activity,... 

The accuracy of a titration calorimeter is normally assessed using the reactions of NaOH(aq) with HCl(aq) or HCICUjaq) [209,210], The dissolution of crystalline tris(hydroxymethyl)aminomethane (THAM) in HCl(aq) has also been employed when the apparatus is equipped with a system for the introduction of solid samples (e.g., an ampule breaking device) [210]. As mentioned in chapter 8, the latter method is commonly recommended for testing conventional reaction-solution calorimeters [39,40]. 

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