Optimization of an Alternative Methodology for Simultaneous Analysis of Nitrite and Nitrate in Water from Urban Stream by Capillary Electrophoresis under Direct UV Detection

Marcone Augusto Leal de Oliveira, Denise do Carmo Soares, Gláucia Soares Tostes, Mara do Carmo Guimarães, Fernando Antonio Simas Vaz

Departamento de Biologia, Universidade Federal de Juiz de Fora, Cidade Universitária, Juiz de Fora, Brazil.
Departamento de Química, Instituto de Ciências Exatas, Universidade Federal de Juiz de Fora, Juiz de Fora, Brazil.

DOI: 10.4236/ajac.2012.37064                

Abstract

An alternative methodology for simultaneous determination of nitrite and nitrate by capillary zone electrophoresis using direct detection UV at 210 nm under reverse electrosmotic flow is proposed. The choice of the electrolyte composition has taken account: the mobility of the anion buffer and of the solutes; the low absorbance of the buffer in 210 nm; high base line stability and analysis time. The electrolyte optimized has consisted of 100 mmol.L–1 TRIS/HCl buffer and 0.15 mmol.L–1 CTAB at pH 8.2. The proposed method was applied successfully in the analysis of nitrite and nitrate in samples from urban stream in the absence of usual sample pretreatment.

Keywords

Capillary Electrophoresis; Nitrite; Nitrate; Urban Stream

Conflicts of Interest

The authors declare no conflicts of interest.

References

[1]	Ministério da Saúde, “Controle e Vigilancia da Qualidade da água para Consumo Humano e seu Padr?o de Controle e Vigilancia da Qualidade da água para Consumo Humano e seu Padr?o de Potabilidade,” Diário Oficial da Uni?o, Portaria 1.469/2000, 2001.
[2]	F. A. Esteves, “Fundamentos de Limnologia,” Interciência, FINEP, Rio de Janeiro, 1998, p. 575.
[3]	R. N. Sah, “Nitrate-Nitrogen Determination—A Critical Review,” Communications in Soil Science and Plant Analysis, Vol. 25, No. 17-18, 1994, pp. 2841-2869. doi:10.1080/00103629409369230
[4]	K. A. Anderson and T. E. Case, “Evaluation of Plant Nitrate Extraction Techniques and Effect on Commonly Used Analytical Methods of Detection,” Communications in Soil Science and Plant Analysis, Vol. 30, No. 9, 1999, pp. 1479-1495. doi:10.1080/00103629909370301
[5]	J. Salomez and G. Hofman, “Nitrate Extraction from Fresh Plant Material by Means of a Methanol: Water Extraction Solution,” Communications in Soil Science and Plant Analysis, Vol. 33, No. 15-18, 2002, pp. 3397-3404. doi:10.1081/CSS-120014533
[6]	P. Mikuska and Z. Vecera, “Simultaneous Determination of Nitrite and Nitrate in Water by Chemiluminescent Flow-Injection Analysis,” Analytica Chimica Acta, Vol. 495, No. 1-2, 2003, pp. 225-232. doi:10.1016/j.aca.2003.08.013
[7]	P. Guozhen, X. Qingi and F. Mei, “Sequential Spectrophotometric Determination of Microgram Amounts of Nitrate and Nitrite in Mixtures,” Microchemical Journal, Vol. 60, No. 3, 1998, pp. 258-265. doi:10.1006/mchj.1998.1669
[8]	L. Monser, S. Sadok, G. M. Greenway, I. Shah and R. F. Uglow, “A Simple Simultaneous Flow Injection Method Based on Phosphomolybdenum Chemistry for Nitrate and Nitrite Determinations in Water and Fish Samples,” Talanta, Vol. 57, No. 3, 2002, pp. 511-518. doi:10.1016/S0039-9140(02)00057-7
[9]	M. J. Moorcroft, J. Davis and R. G. Compton, “Detection and Determination of Nitrate and Nitrite: A Review,” Talanta, Vol. 54, No. 5, 2001, pp. 785-803. doi:10.1016/S0039-9140(01)00323-X
[10]	M. G. Z. Baumgartem, J. M. B. Rocha and L. F. H. Nien-cheski, “Manual de Análises de Oceonografia Química,” Editora FURG, Rio Grande, 1996.
[11]	M. F. M. Tavares, “Eletroforese Capilar: Conceitos Básicos,” Química Nova, Vol. 19, No. 2, 1996, pp. 173-181.
[12]	M. Bier, “Electrophoresis—Theory, Methods and Applications,” Academic Press Inc., New York, 1959.
[13]	Z. Deyl, “Electrophoresis,” Journal of Chromatography Library, Vol. 18, 1979, pp. 345-362.
[14]	C. Bjergegaard, P. Moiler and H. Sorensen, “Determination of Thiocyanate, Iodide, Nitrate and Nitrite in Biological Samples by Micellar Electrokinetic Capillary Chromatography,” Journal of Chromatography, Vol. 717, No. 1-2, 1995, pp. 409-414.
[15]	S. A. Oehrle, “Analysis of Anions in Drinking Water by Capillary Ion Electrophoresis,” Journal of Chromatography, Vol. 733, No. 1-2, 1996, pp. 101-104. doi:10.1016/0021-9673(95)00769-5
[16]	P. N. Bories, E. Scherman and L. Dziedzic, “Analysis of Nitrite and Nitrate in Biological Fluids by Capillary Electrophoresis,” Clinical Biochemistry, Vol. 32, No. 1, 1999, pp. 9-14. doi:10.1016/S0009-9120(98)00090-3
[17]	R. Bodor, V. Madajova, D. Kanianskya, M. Masar, M. Johnck and B. Stanislawski, “Isotachophoresis and Isotachophoresis—Zone Electrophoresis Separations of Inorganic Anions Present in Water Samples on a Planar Chip with Column-Coupling Separation Channels and conductivity Detection,” Journal of Chromatography A, Vol. 916, No. 1-2, 2001, pp. 155-165. doi:10.1016/S0021-9673(00)01080-3
[18]	M. C. Mart, G. Bocaz, E. Asp and M. Roeckel, “Simultaneous Determination of NO and NO in Fisheries Waste-waters High in Chloride Concentration by Capillary Ion Electrophoresis with Direct UV Detection,” Biotechnology Techniques, Vol. 11, No. 3, 1997, pp. 163-166. doi:10.1023/A:1018449429551
[19]	A. F. Faria, M. V. N. Souza, M. V. Almeida and M. A. L. Oliveira, “Simultaneous Separation of Five Fluoroquinolone Antibiotics by Capillary Zone Electrophoresis,” Analytica Chimica Acta, Vol. 579, No. 2, 2006, pp. 185- 192. doi:10.1016/j.aca.2006.07.037
[20]	D. A. Skoog, D. M. West and F. J. Holler, “Fundamentals of Analytical Chemistry,” 7a ed., Saunders, Philadelphia, 1992, pp. 575