Abstract
The mixed dissociation constant of naphazoline is determined at various ionic strengths I [mol dm−3] in the range of 0.01 to 0.26 and at temperatures of 25°C and 37°C using ESAB and HYPERQUAD regression analysis of the potentiometric titration data. A strategy of efficient experimentation is proposed in a protonation constant determination, followed by a computational strategy for the chemical model with a protonation constant determination. Two group parameters, L 0 and H T were ill-conditioned in the model and their determination is therefore uncertain. These group parameters, L 0 and H T, can significantly influence a systematic error in the estimated common parameter pKa and they always should be refined together with pK a. The thermodynamic dissociation constant pK aT was estimated by nonlinear regression of {pK a, I} data at 25°C and 37°C: for naphazoline pK alT = 10.41(1) and 10.13(2). Goodness-of-fit tests for various regression diagnostics enabled the reliability of the parameter estimates to be found. 
[1] S. Casado-Terrones, J.F. Fernandez-Sanchez, B.C. Diaz, A.S. Carretero, A. Fernandez-Gutierrez, Journal of Pharmaceutical and Biomedical Analysis 38, 785 (2005) http://dx.doi.org/10.1016/j.jpba.2005.02.01810.1016/j.jpba.2005.02.018Search in Google Scholar
[2] A. Goodmann-HiIlman, T. Rall, A. Nier, P. Taylor, the Pharmacologycal Basic of Therapeutic (McGraw-Hill, New York, 1996) Search in Google Scholar
[3] P. Chocholous, D. Satinsky, P. Solich, Talanta 70, 408 (2006) http://dx.doi.org/10.1016/j.talanta.2006.02.06510.1016/j.talanta.2006.02.065Search in Google Scholar
[4] S. Goenechea, Journal of Chromatography A 36, 375 (1968) http://dx.doi.org/10.1016/S0021-9673(01)92963-210.1016/S0021-9673(01)92963-2Search in Google Scholar
[5] H.C. Goicoechea, A.C. Olivieri, Analytica Chimica Acta 453, 289 (2002) http://dx.doi.org/10.1016/S0003-2670(01)01232-610.1016/S0003-2670(01)01232-6Search in Google Scholar
[6] K.M. Kelani, Journal of AOAC International 81, 1128 (1998) 10.1093/jaoac/81.6.1128Search in Google Scholar
[7] M. Massaccesi, Pharmaceutica Acta Helvetiae 62, 302 (1987) Search in Google Scholar
[8] R. Bocic, C. Vallejos, A.A. lvarez-Luege, F. Lo’pez, J. AOAC Int. 75, 902 (1992) 10.1093/jaoac/75.5.902Search in Google Scholar
[9] S.C. Ruckmick, D.F. Marsh, S.T. Duong, Journal of Pharmaceutical Sciences, 84, 502 (1995) http://dx.doi.org/10.1002/jps.260084042210.1002/jps.2600840422Search in Google Scholar
[10] A.F. Marchesini, M.R. Williner, V.E. Mantovani, J.C. Robles, H.C. Goicoechea, Journal of Pharmaceutical and Biomedical Analysis 31, 39 (2003) http://dx.doi.org/10.1016/S0731-7085(02)00600-310.1016/S0731-7085(02)00600-3Search in Google Scholar
[11] J.M. Lemus Gallego, J. Pérez Arroyo, Journal of Chromatography B 784, 39 (2003) http://dx.doi.org/10.1016/S1570-0232(02)00748-110.1016/S1570-0232(02)00748-1Search in Google Scholar
[12] J.M. Lemus Gallego, J. Pérez Arroyo, Journal of Separation Science 26, 947 (2003) http://dx.doi.org/10.1002/jssc.20030150710.1002/jssc.200301507Search in Google Scholar
[13] S. Khalil, Microchimica Acta 130, 181 (1999) http://dx.doi.org/10.1007/BF0124492510.1007/BF01244925Search in Google Scholar
[14] J.L. Manzoori, M. Amjadi, Indian J. Chem. A 42, 2988 (2003) Search in Google Scholar
[15] S.L. McCall, J.D. Winefordner, Analytical Chemistry 55, 391 (1983) http://dx.doi.org/10.1021/ac00253a05310.1021/ac00253a053Search in Google Scholar
[16] A.S. Carretero, C.C. Blanco, B.C. Diaz, A.F. Gutierrez, Analyst 123, 1069 (1998) http://dx.doi.org/10.1039/a708672e10.1039/a708672eSearch in Google Scholar
[17] A.F. Gutierrez, A.S. Carretero, B.C. Diaz, C.C. Blanco, Applied Spectroscopy 53, 741 (1999) http://dx.doi.org/10.1366/000370299194719910.1366/0003702991947199Search in Google Scholar
[18] I. Shoukrallah, Acta Pharmaceutica Jugoslavica 41, 107 (1991) 10.1080/00015129109438591Search in Google Scholar
[19] S.M. Sabry, M.H. Abdel-Hay, M.H. Barary, T.S. Belal, Journal of Pharmaceutical and Biomedical Analysis 22, 257 (2000) http://dx.doi.org/10.1016/S0731-7085(99)00261-710.1016/S0731-7085(99)00261-7Search in Google Scholar
[20] G. Santoni, P. Mura, S. Pinzauti, P. Gratteri, E. Laporta, International Journal of Pharmaceutics 50, 75 (1989) http://dx.doi.org/10.1016/0378-5173(89)90185-310.1016/0378-5173(89)90185-3Search in Google Scholar
[21] J.M.L. Gallego, J.P. Arroyo, Journal of Separation Science 26, 947 (2003) http://dx.doi.org/10.1002/jssc.20030150710.1002/jssc.200301507Search in Google Scholar
[22] A. Salinas-Castillo, A.S. Carretero, A. Fernandez-Gutierrez, Analytical and Bioanalytical Chemistry 376, 1111 (2003) http://dx.doi.org/10.1007/s00216-003-2052-510.1007/s00216-003-2052-5Search in Google Scholar PubMed
[23] H.C. Goicoechea, A.C. Olivieri, Analyst 126, 1105 (2001) http://dx.doi.org/10.1039/b100422k10.1039/b100422kSearch in Google Scholar PubMed
[24] Y. Liang, Q. Huang, Yaowu Fenxi Zazhi 5, 81 (1985) Search in Google Scholar
[25] M. Meloun, T. Syrovy, A. Vrana, Talanta 62, 511 (2004) http://dx.doi.org/10.1016/j.talanta.2003.08.02710.1016/j.talanta.2003.08.027Search in Google Scholar
[26] C. Rigano, M. Grasso, S. Sammartano, Annali Di Chimica 74, 537 (1984) Search in Google Scholar
[27] C. De Stefano, P. Princi, C. Rigano, S. Sammartano, Annali di Chimica 77, 643 (1987) Search in Google Scholar
[28] S. Capone, A. Derobertis, C. Destefano, S. Sammartano, R. Scarcella, Talanta 34, 593 (1987) http://dx.doi.org/10.1016/0039-9140(87)80198-410.1016/0039-9140(87)80198-4Search in Google Scholar
[29] P. Gans, A. Sabatini, A. Vacca, Talanta 43, 1739 (1996) http://dx.doi.org/10.1016/0039-9140(96)01958-310.1016/0039-9140(96)01958-3Search in Google Scholar
[30] M. Meloun, J. Havel, E. Högfeldt, Computation of solution equilibria: a guide to methods in potentiometry, extraction, and spectrophotometry (Ellis Horwood Chichester, England, 1988) 10.1016/S0003-2670(00)85305-2Search in Google Scholar
[31] M. Meloun, M. Bartos, E. Hogfeldt, Talanta 35, 981 (1988) http://dx.doi.org/10.1016/0039-9140(88)80233-910.1016/0039-9140(88)80233-9Search in Google Scholar
[32] M. Meloun, J. Militký, M. Forina, Chemometrics for analytical chemistry. PC-aidedregression and related mathods (Ellis Horwood, Chichester, 1994) Volume 2 Search in Google Scholar
[33] M. Meloun, J. Militký, M. Forina, Chemometrics for analytical chemistry. PC-Aided Statistical Data Analysis (Ellis Horwood, Chichester, 1992) Volume 1 Search in Google Scholar
[34] P.M. May, D.R. Williams, P.W. Linder, R.G. Torrington, Talanta 29, 249 (1982) http://dx.doi.org/10.1016/0039-9140(82)80108-210.1016/0039-9140(82)80108-2Search in Google Scholar
[35] M. Meloun, V. Riha, J. Zacek, Chemicke Listy 82, 765 (1988) Search in Google Scholar
[36] T.S.S. Ltd., (TriloByte Statistical Software Ltd., Pardubice, Czech republic, 1990 and 1999) Search in Google Scholar
© 2011 Versita Warsaw
This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.
