Abstract
In this study, a very simple spectrophotometric method for the simultaneous determination of citric and ascorbic acid based on the reaction of these acids with a copper(II)-ammonia complex is presented. The Cu2+-NH3 complex (with λmax = 600 nm) was decomposed by citrate ion and formed a Cu2+-citrate complex (with λmax = 740 nm). On the other hand, during the reaction of ascorbic acid with copper(II)-ammonia complex, ascorbic acid is oxidized and the copper(II)-ammonia complex is reduced to the copper(I)-ammonia complex and the absorbance decreases to 600 nm. Although there is a spectral overlap between the absorbance spectra of complexes Cu2+-NH3 and Cu2+-citrate, they have been simultaneously determined using an artificial neural network (ANN). The absorbances at 600 and 740 nm were used as the input layer. The ANN architectures were different for citric and ascorbic acid. The output of the citric acid ANN architecture was used as an input node for the ascorbic acid ANN architecture. This modification improves the capability of the ascorbic acid ANN model for the prediction of ascorbic acid concentrations. The dynamic ranges for citric and ascorbic acid were 1.0–125.0 and 1.0–35.0 mM, respectively. Finally, the proposed method was successfully applied to the determination of citric and ascorbic acids in vitamin C tablets and some powdered drink mixes.
Similar content being viewed by others
References
Szekely, E., Talanta, 1985, vol. 32, no. 2, p. 153.
Gitotti, S., Budini, R., Gattavecchia, E., and Tonelli, D., Anal. Chim. Acta, 1981, vol. 124, no. 1, p. 215.
Indyk, H. and Kurmann, A., Analyst, 1987, vol. 112, p. 1173.
Romero, E.G., Munoz, G.S., Alvarez, P.J.M., and Ibanez, M.D.C., J. Chromatogr., 1993, vol. 655, no. 1, p. 111.
Ashoor, S. and Knox, M., J. Chromatogr., 1984, vol. 299, p. 288.
Morvai, M., Perl, I.M., and Knausz, D., J. Chromatogr., 1991, vol. 552, p. 337.
Samuella, B.S. and Dale, E.W., J. Chem. Educ., 2004, vol. 81, no. 10, p. 1479.
Ferreire, S., Bandeira, M., and Lemos, V., Fresenius J. Anal. Chem., 1997, vol. 357, no. 8, p. 1174.
Abdelmageed, O.H., Khashaba, P.Y., and Askal, H.F., Talanta, 1995, vol. 42, no. 4, p. 573.
Safavi, A. and Fotouhi, L., Talanta, 1994, vol. 41, no. 8, p. 1225.
Farajzadeh, M.A. and Nagizadeh, S., J. Chin. Chem. Soc., 2002, vol. 49, p. 619.
Farajzadeh, M.A. and Nagizadeh, S., Zhurn. Anal. Chem., 2003, vol. 58, no. 10, p. 1037 [J. Anal. Chem. (Engl. Transl.), vol. 58, no. 10, p. 927].
Sultan, S. and Walmsley, A., Analyst, 1997, vol. 122, no. 12, p. 1601.
Zhanguo, C. and Jiuru, L., J. Chromatogr. Sci., 2002, vol. 40, no. 1, p. 35.
Oderiz, M.L.V., Blanco, M.E.V., Hernandez, J.L., Lozano, J.S., and Rodrigues, M.A.R., J. AOAC Int., 1994, vol. 77, p. 1056.
Guo, D.H. and Xia, L., Se Pu, 2001, vol. 19, p. 276.
Chinnic, F., Spinabelli, U., Riponi, C., and Amati, A., J. Food Comp. Anal., 2005, vol. 18, nos. 2–3, p. 121.
Author information
Authors and Affiliations
Corresponding author
Additional information
The text was submitted by the authors in English.
Rights and permissions
About this article
Cite this article
Zarei, K., Atabati, M. & Karimian, N. Simultaneous dual wavelength spectrophotometric determination of citric and ascorbic acids using an artificial neural network. J Anal Chem 63, 145–150 (2008). https://doi.org/10.1134/S106193480802007X
Received:
Published:
Issue Date:
DOI: https://doi.org/10.1134/S106193480802007X