JOURNAL ARTICLE

Modeling ATP protonation and activity coefficients in NaClaq and KClaq by SIT and Pitzer equations

Concetta De Stefano, Demetrio Milea, Alberto Pettignano, Silvio Sammartano
Biophysical Chemistry 2006 May 20, 121 (2): 121-30
16488529
The acid-base properties of Adenosine 5'-triphosphate (ATP) in NaCl and KCl aqueous solutions at different ionic strengths (0<I/mol L(-1)<or=5 for NaCl(aq), 0<I/mol L(-1)<or=3 for KCl(aq)) and at t=25 degrees C were investigated. A selection of literature data on ATP protonation constants and on activity isopiestic coefficients was performed, together with new potentiometric measurements (by ISE-H(+), glass electrode). Both literature and new experimental data were used to model the dependence on ionic strength and ionic medium of ATP protonation by SIT (Specific ion Interaction Theory) and Pitzer equations. In addition to values of first and second ATP protonation constants in NaCl(aq) and KCl(aq) at different ionic strengths, stability constants of NaATP(3-) and KATP(3-) complexes, SIT interaction coefficients and Pitzer parameters were calculated, together with protonation constants at infinite dilution: log (T)K(1)(H)=p(T)K(a2)=7.656+/-0.010 and log (T)K(2)(H)=p(T)K(a1)=4.561+/-0.006 (in the molar concentration scale, +/-95% confidence interval). Both SIT and Pitzer approaches give satisfactory results.

Full Text Links

Find Full Text Links for this Article

Discussion

You are not logged in. Sign Up or Log In to join the discussion.

Related Papers

Remove bar
Read by QxMD icon Read
16488529
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"