Abstract
The simultaneous determination of NH4 + and K+ in solution has been attempted using a potentiometric sensor array and multivariate calibration. The sensors used are rather non-specific and of all-solid-state type, employing polymeric (PVC) membranes. The subsequent data processing is based on the use of a multilayer artificial neural network (ANN). This approach is given the name "electronic tongue" because it mimics the sense of taste in animals. The sensors incorporate, as recognition elements, neutral carriers belonging to the family of the ionophoric antibiotics. In this work the ANN type is optimized by studying its topology, the training algorithm, and the transfer functions. Also, different pretreatments of the starting data are evaluated. The chosen ANN is formed by 8 input neurons, 20 neurons in the hidden layer and 2 neurons in the output layer. The transfer function selected for the hidden layer was sigmoidal and linear for the output layer. It is also recommended to scale the starting data before training. A correct fit for the test data set is obtained when it is trained with the Bayesian regularization algorithm. The viability for the determination of ammonium and potassium ions in synthetic samples was evaluated; cumulative prediction errors of approximately 1% (relative values) were obtained. These results were comparable with those obtained with a generalized regression ANN as a reference algorithm. In a final application, results close to the expected values were obtained for the two considered ions, with concentrations between 0 and 40 mmol L−1.
Similar content being viewed by others
References
Gardner JW, Bartlett PN (1999) Electronic noses. Principles and applications. Oxford University Press, Oxford
Vlasov Y, Legin A (1998) Fresenius J Anal Chem 361:255–260
Toko K (2000) Biomimetic sensor technology. Cambridge University Press, Cambridge, pp 29–39
Lavine BK, Workman J (2002) Anal Chem 74:2763–2770
Otto M, Thomas JDR (1985) Anal Chem 57:2647–2651
Beebe K, Uerz D, Sandifer J, Kowalski B (1988) Anal Chem 60:66–71
Beebe K, Kowalski B (1988) Anal Chem 60:2273–2278
Forster RJ, Regan F, Diamond D (1991) Anal Chem 63:876–882
Bos M, Bos A, Van der Linden WE (1990) Anal Chim Acta 233:31–39
Bos M, Bos A, Van der Linden WE (1993) Analyst 118:323–328
Despagne F, Massart DL (1998) Analyst 123:157R–178R
Chan WH, Lee A, Kwong D, Liang Y, Wang K (1997) Analyst 122:657–661
Evans P, Persaud K, McNeish A, Sneath R, Hobson N, Magan N (2000) Sens Actuators B 69:348–358
Legin A, Rudnitskaya A, Vlasov Y, Di Natale C, Mazzone E, D'Amico A (2000) Sens Actuators B 65:232–235
Baret M, Massart DL, Fabry P, Conesa F, Eichner C, Menardo C (2000) Talanta 51:863–877
Alegret S (2003) (ed) Integrated analytical systems. Elsevier, Amsterdam
Toko K (2000) Sens Actuators B 64:205–206
Krantz-Rülcker C, Stenberg M, Winquist F, Lundström I (2001) Anal Chim Acta 425:217–226
Di Natale C, Paolesse R, Macagnano A, Mantini A, D'Amico A, Legin A, Lvova A, Rudnitskaya A, Vlasov Y (2000) Sens Actuators B 64:15–21
Legin A, Rudnitskaya A, Vlasov Y, Di Natale C, Davide F, D'Amico A (1997) Sens Actuators B 44:291–296
Lvova L, Kim SS, Legin A, Vlasov Y, Yang JS, Cha GS, Nam H (2002) Anal Chim Acta 468:303–314
Alegret A, Martínez-Fábregas E, (1989) Biosensors 4:287–297
Alegret S, Florido A (1991) Analyst 116:473–476
Davies OG, Moody GJ, Thomas JDR (1998) Analyst 113:497–500
Sheen H, Cardwell TJ, Cattrall RW (1998) Analyst 123:2181–2184
Tohda K, Suzuki K, Aruga H, Matsuzoe M, Inove H, Shirai T (1988) Anal Chem 60:1714–1721
Fujiwara M (1991) Clin Chem 37/8:1375–1378
Tohda K, Suzuki K, Kusoga N, Watanabe K, Nagashima H, Inove H, Shirai T (1990) Anal Chem 62:936–942
Umezawa Y (1990) (ed) Handbook of ion-selective electrodes selectivity coefficients. CRC Press, Boca Raton, FL
Umezawa Y, Umezawa K, Sato H (1995) Pure Appl Chem 67:507–518
Freeman JA, Skapura DM (1991) Neural networks, algorithms, applications, and programming techniques. Addison-Wesley, Reading, MA
Demuth H, Beale M (1992) Neural network toolbox, for use with MATLAB. Mathworks Inc., Natick, MA
Foresee FD, Hagan MT (1997) Proc 1997 Int Joint Conf on Neural Networks. Houston, TX, pp 1930–1935
MacKay JC (1995) Network-Comp Neural Syst 6:469–505
Specht DF (1991) IEEE Trans Neural Networks 2:568–576
Acknowledgements
Financial support for this work is provided by MCyT (Madrid, Spain) through projects PPQ2001-1950 and BIO2000-0681, and by the Department d'Universitats, Recerca, i Societat de la Informació, DURSI (Generalitat de Catalunya). Mobility of researchers was possible through an AIRE2000 grant, also from DURSI.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Gallardo, J., Alegret, S., Muñoz, R. et al. An electronic tongue using potentiometric all-solid-state PVC-membrane sensors for the simultaneous quantification of ammonium and potassium ions in water. Anal Bioanal Chem 377, 248–256 (2003). https://doi.org/10.1007/s00216-003-2042-7
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00216-003-2042-7