Department of Analytical Chemistry, University of Pardubice, Namesti Cs. Legii 565, CZ-532 10 Pardubice, Czech Republic.
Talanta. 2004 Feb 27;62(3):511-22. doi: 10.1016/j.talanta.2003.08.027.
The mixed dissociation constants of five drug acids-ambroxol, antazoline, naphazoline, oxymetazoline and ranitidine-at various ionic strengths I of range 0.01 and 1.0 and at temperatures of 25 and 37 degrees C were determined using SQUAD(84) regression analysis of the pH-spectrophotometric titration data. A proposed strategy of efficient experimentation in a protonation constants determination, followed by a computational strategy for the chemical model with a protonation constants determination, is presented on the protonation equilibria of ambroxol. The thermodynamic dissociation constant pK(a)(T) was estimated by non-linear regression of {pK(a), I} data at 25 and 37 degrees C: for ambroxol p K (a ,1)(T )=8.05 (6) and 8.25 (4), logbeta (21)(T )=11.67 (6) and 11.83 (8), for antazoline p K (a ,1)(T )=7.79 (2) and 7.83 (6), p K (a ,2)(T )=9.74 (3) and 9.55 (2), for naphazoline pK (a ,1)(T )=10.81 (1) and 10.63 (1), for oxymethazoline pK (a ,1)(T )=10.62 (2) and 10.77 (7), pK(a,2)(T)=12.03(3) and 11.82 (4) and for ranitidine p K (a ,1)(T )=1.89 (1) and 1.77 (1). Goodness-of-fit tests for various regression diagnostics enabled the reliability of the parameter estimates to be found.
采用 SQUAD(84) 回归分析方法，在 25 和 37°C 温度下，在 0.01 和 1.0 的范围离子强度 I 下，测定了 5 种药物酸（氨溴索、安特唑啉、萘甲唑啉、羟甲唑啉和雷尼替丁）的混合离解常数。提出了一种有效的实验策略，用于确定质子化常数，然后提出了一种用于具有质子化常数的化学模型的计算策略，用于氨溴索的质子化平衡。在 25 和 37°C 下，通过非线性回归{pK(a), I}数据，估算热力学离解常数 pK(a)(T)：对于氨溴索，pK(a,1)(T)=8.05(6)和 8.25(4)，logbeta(21)(T)=11.67(6)和 11.83(8)，对于安特唑啉，pK(a,1)(T)=7.79(2)和 7.83(6)，pK(a,2)(T)=9.74(3)和 9.55(2)，对于萘甲唑啉，pK(a,1)(T)=10.81(1)和 10.63(1)，对于羟甲唑啉，pK(a,1)(T)=10.62(2)和 10.77(7)，pK(a,2)(T)=12.03(3)和 11.82(4)，对于雷尼替丁，pK(a,1)(T)=1.89(1)和 1.77(1)。通过各种回归诊断的拟合优度检验，可以找到参数估计的可靠性。
