Buffers for the physiological pH range: thermodynamic constants of four substituted aminoethanesulfonic acids from 5 to 50.degree.C

A compendium of temperature responses of Rubisco kinetic traits: variability among and within photosynthetic groups and impacts on photosynthesis modeling

“…However, in the case of zwitterionic buffers, e.g. for HEPES (Vega and Bates, 1976; Feng et al , 1989; Roy et al , 2009) and Bicine (Datta et al , 1964; Azab et al , 1994; Roy et al , 2006), the effect of I s was not always important (but see Bates and Hetzer, 1961; Durst and Staples, 1972; Bates and Robinson, 1973; Ramette et al , 1977 for the I s dependence of Tris). Given the p K a dependence on I s and the I s dependence on p K a , I s and p K a for the given buffer solution were ultimately calculated iteratively.…”

Thermodynamics of the Second Dissociation Constants (pK<sub>2</sub>) of Piperazine-N,N′-bis-2-hydroxypropanesulfonic Acid (POPSO Sesquisodium Salt) and Associated Thermodynamic Functions from (278.15 to 328.15) K

“…Examples of structurally similar compounds are; N-substituted amino sulfonic acids, (TABS) [9], (MOBS) [11] and (AMPSO) [10] [18]. These are the parent compounds (TAURINE) [19], (MORPHOLINE) [20], and (PIPERAZINE) [5] [21], respectively. The value of pK 2 of (PIPES) [4] at 298.15 K is 7.1399; whereas, that for a similar structure (POPSO) from the present study is 7.8029.…”

Optimization and Enhancement of the Peroxidase-like Activity of Hemin in Aqueous Solutions of Sodium Dodecylsulfate

“…75 The abbreviations "HEPES" and "HEPES − " were used in the MD simulations. The reported piperazine pK a2 value of HEPES at 25 °C is 7.6 73,74 Therefore, at pH = 7.2, HEPES is expected to exist predominantly in its acidic form ([HEPES]:[HEPES − ] = 2:1). 25,50,100,200, or 300 mM HEPES were prepared at room temperature (RT) by dissolving HEPES in Milli-Q water and adjusting the pH value to 7.2 by addition of 2 M NaOH.…”

“…TMB has been well-known for many years for measuring the activity of HRP ,− or peroxidase-mimicking systems − under acidic conditions (often pH 4–6). HEPES (= 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid) − was applied to buffer the reaction solutions at pH = 7.2 (Figure ), in most cases at a concentration of 100 mM. A pH value of 7.2 was arbitrarily chosen because of previous work on HRP. , Molecular dynamics (MD) simulations were carried out to gain insight into the interaction between hemin and HEPES (as a possible axial ligand of hemin) and between hemin and SDS.…”