INQUISUR   21779
INSTITUTO DE QUIMICA DEL SUR
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Electrophoretic method for the determination of sulfonylureas in grain samples using a continuous flow system for SPE step and ionic liquid with dispersed carbon nanotubes as electrolyte solution
Autor/es:
VALERIA H. SPRINGER; FRANCISCO APRILE; ADRIANA G. LISTA
Reunión:
Conferencia; 12th International Conference on Flow Analysis; 2012
Resumen:
Electrophoretic method for the determination of sulfonylureas in grain samples using a continuous flow system for SPE step and ionic liquid with dispersed carbon nanotubes as electrolyte solution. Valeria Springer*, Francisco Aprile, Adriana Lista. Analytical Chemistry Section, INQUISUR UNS - CONICET. Av. Alem 1253. Bah¨ªa Blanca, Buenos Aires, Argentina.- CONICET. Av. Alem 1253. Bah¨ªa Blanca, Buenos Aires, Argentina. *e-mail: valeria.springer@uns.edu.are-mail: valeria.springer@uns.edu.ar In the last years, ionic liquids (ILs) have been widely used as ¡°green solvents¡± replacing traditional organic solvents in all areas of separation science because of their unique properties *1+. Specially, the room temperature ionic liquids (RTILs) have been used in different separation techniques *2, 3+. On the other hand, the carbon nanotubes (CNTs) have been widely applied in analytical chemistry due to their special physical/chemical properties *4, 5+. The purpose of the present study is to investigate the potential application of ionic liquids as main component of the separation solution in capillary electrophoresis (CE). Moreover, single walled carbon nanotubes (SWCNTs) are proposed as additive into the background electrolyte solution (BGE) with the aim of improve the resolution of the peaks of analytes. Sulfonylurea herbicides are proposed as target analytes due to they are commonly employed in Argentina for weed control in crops. Moreover, the use of a previous solid phase extraction step (SPE) is necessary when complex matrixes are analyzed. So, a continuous flow system was used prior to CE analysis. The determination was done in wheat and sorghum samples. So, the pesticides extraction was done with a common extraction solution and after this a simple SPE step was included by using a C18 minicolumn placed in a continuous flow system. The results showed that a 10 mM solution of 1-butyl-3-methyl imidazolium tetrafluoroborate with 2 mg L-1 of SWCNTs was a satisfactory running buffer solution to determine chlorsulfuron, sulfometuron methyl, nicosulfuron and ethoxysulfuron, with LODs between 16.8 and 26.6 ¦Ìg kg-1, lower than the maximum residue limits (MRLs) established by EU for these analytes in both samples (100 ¦Ìg kg-1 for chlorsulfuron and 50 ¦Ìg kg- limits (MRLs) established by EU for these analytes in both samples (100 ¦Ìg kg-1 for chlorsulfuron and 50 ¦Ìg kg- nicosulfuron and ethoxysulfuron, with LODs between 16.8 and 26.6 ¦Ìg kg-1, lower than the maximum residue limits (MRLs) established by EU for these analytes in both samples (100 ¦Ìg kg-1 for chlorsulfuron and 50 ¦Ìg kg- limits (MRLs) established by EU for these analytes in both samples (100 ¦Ìg kg-1 for chlorsulfuron and 50 ¦Ìg kg- L-1 of SWCNTs was a satisfactory running buffer solution to determine chlorsulfuron, sulfometuron methyl, nicosulfuron and ethoxysulfuron, with LODs between 16.8 and 26.6 ¦Ìg kg-1, lower than the maximum residue limits (MRLs) established by EU for these analytes in both samples (100 ¦Ìg kg-1 for chlorsulfuron and 50 ¦Ìg kg- limits (MRLs) established by EU for these analytes in both samples (100 ¦Ìg kg-1 for chlorsulfuron and 50 ¦Ìg kg- nicosulfuron and ethoxysulfuron, with LODs between 16.8 and 26.6 ¦Ìg kg-1, lower than the maximum residue limits (MRLs) established by EU for these analytes in both samples (100 ¦Ìg kg-1 for chlorsulfuron and 50 ¦Ìg kg- limits (MRLs) established by EU for these analytes in both samples (100 ¦Ìg kg-1 for chlorsulfuron and 50 ¦Ìg kg- -butyl-3-methyl imidazolium tetrafluoroborate with 2 mg L-1 of SWCNTs was a satisfactory running buffer solution to determine chlorsulfuron, sulfometuron methyl, nicosulfuron and ethoxysulfuron, with LODs between 16.8 and 26.6 ¦Ìg kg-1, lower than the maximum residue limits (MRLs) established by EU for these analytes in both samples (100 ¦Ìg kg-1 for chlorsulfuron and 50 ¦Ìg kg- limits (MRLs) established by EU for these analytes in both samples (100 ¦Ìg kg-1 for chlorsulfuron and 50 ¦Ìg kg- nicosulfuron and ethoxysulfuron, with LODs between 16.8 and 26.6 ¦Ìg kg-1, lower than the maximum residue limits (MRLs) established by EU for these analytes in both samples (100 ¦Ìg kg-1 for chlorsulfuron and 50 ¦Ìg kg- limits (MRLs) established by EU for these analytes in both samples (100 ¦Ìg kg-1 for chlorsulfuron and 50 ¦Ìg kg- -1 of SWCNTs was a satisfactory running buffer solution to determine chlorsulfuron, sulfometuron methyl, nicosulfuron and ethoxysulfuron, with LODs between 16.8 and 26.6 ¦Ìg kg-1, lower than the maximum residue limits (MRLs) established by EU for these analytes in both samples (100 ¦Ìg kg-1 for chlorsulfuron and 50 ¦Ìg kg- limits (MRLs) established by EU for these analytes in both samples (100 ¦Ìg kg-1 for chlorsulfuron and 50 ¦Ìg kg- -1, lower than the maximum residue limits (MRLs) established by EU for these analytes in both samples (100 ¦Ìg kg-1 for chlorsulfuron and 50 ¦Ìg kg--1 for chlorsulfuron and 50 ¦Ìg kg- 1 for nicosulfuron and ethoxysulfuron). A recovery study using the so-called matrix matched calibration demonstrates that no matrix interferences were found throughout the determination. The study, at two concentration levels, was carried out to validate the proposed method and the obtained results were over the range 80 - 113 %. In this way, the developed method was suitable to separate four sulfonylureas in 16 min without the use of organic solvents in the buffer solution. The addition of SWCNTs to the buffer made possible the complete separation of the analytes and the resolution was improved. A simple continuous SPE step was used to do the cleanup of the samples and the preconcentration of the analytes, prior to CE analysis. In this way, the developed method was suitable to separate four sulfonylureas in 16 min without the use of organic solvents in the buffer solution. The addition of SWCNTs to the buffer made possible the complete separation of the analytes and the resolution was improved. A simple continuous SPE step was used to do the cleanup of the samples and the preconcentration of the analytes, prior to CE analysis. concentration levels, was carried out to validate the proposed method and the obtained results were over the range 80 - 113 %. In this way, the developed method was suitable to separate four sulfonylureas in 16 min without the use of organic solvents in the buffer solution. The addition of SWCNTs to the buffer made possible the complete separation of the analytes and the resolution was improved. A simple continuous SPE step was used to do the cleanup of the samples and the preconcentration of the analytes, prior to CE analysis. In this way, the developed method was suitable to separate four sulfonylureas in 16 min without the use of organic solvents in the buffer solution. The addition of SWCNTs to the buffer made possible the complete separation of the analytes and the resolution was improved. A simple continuous SPE step was used to do the cleanup of the samples and the preconcentration of the analytes, prior to CE analysis. demonstrates that no matrix interferences were found throughout the determination. The study, at two concentration levels, was carried out to validate the proposed method and the obtained results were over the range 80 - 113 %. In this way, the developed method was suitable to separate four sulfonylureas in 16 min without the use of organic solvents in the buffer solution. The addition of SWCNTs to the buffer made possible the complete separation of the analytes and the resolution was improved. A simple continuous SPE step was used to do the cleanup of the samples and the preconcentration of the analytes, prior to CE analysis. In this way, the developed method was suitable to separate four sulfonylureas in 16 min without the use of organic solvents in the buffer solution. The addition of SWCNTs to the buffer made possible the complete separation of the analytes and the resolution was improved. A simple continuous SPE step was used to do the cleanup of the samples and the preconcentration of the analytes, prior to CE analysis. concentration levels, was carried out to validate the proposed method and the obtained results were over the range 80 - 113 %. In this way, the developed method was suitable to separate four sulfonylureas in 16 min without the use of organic solvents in the buffer solution. The addition of SWCNTs to the buffer made possible the complete separation of the analytes and the resolution was improved. A simple continuous SPE step was used to do the cleanup of the samples and the preconcentration of the analytes, prior to CE analysis. In this way, the developed method was suitable to separate four sulfonylureas in 16 min without the use of organic solvents in the buffer solution. The addition of SWCNTs to the buffer made possible the complete separation of the analytes and the resolution was improved. A simple continuous SPE step was used to do the cleanup of the samples and the preconcentration of the analytes, prior to CE analysis. for nicosulfuron and ethoxysulfuron). A recovery study using the so-called matrix matched calibration demonstrates that no matrix interferences were found throughout the determination. The study, at two concentration levels, was carried out to validate the proposed method and the obtained results were over the range 80 - 113 %. In this way, the developed method was suitable to separate four sulfonylureas in 16 min without the use of organic solvents in the buffer solution. The addition of SWCNTs to the buffer made possible the complete separation of the analytes and the resolution was improved. A simple continuous SPE step was used to do the cleanup of the samples and the preconcentration of the analytes, prior to CE analysis. In this way, the developed method was suitable to separate four sulfonylureas in 16 min without the use of organic solvents in the buffer solution. The addition of SWCNTs to the buffer made possible the complete separation of the analytes and the resolution was improved. A simple continuous SPE step was used to do the cleanup of the samples and the preconcentration of the analytes, prior to CE analysis. concentration levels, was carried out to validate the proposed method and the obtained results were over the range 80 - 113 %. In this way, the developed method was suitable to separate four sulfonylureas in 16 min without the use of organic solvents in the buffer solution. The addition of SWCNTs to the buffer made possible the complete separation of the analytes and the resolution was improved. A simple continuous SPE step was used to do the cleanup of the samples and the preconcentration of the analytes, prior to CE analysis. In this way, the developed method was suitable to separate four sulfonylureas in 16 min without the use of organic solvents in the buffer solution. The addition of SWCNTs to the buffer made possible the complete separation of the analytes and the resolution was improved. A simple continuous SPE step was used to do the cleanup of the samples and the preconcentration of the analytes, prior to CE analysis. study, at two concentration levels, was carried out to validate the proposed method and the obtained results were over the range 80 - 113 %. In this way, the developed method was suitable to separate four sulfonylureas in 16 min without the use of organic solvents in the buffer solution. The addition of SWCNTs to the buffer made possible the complete separation of the analytes and the resolution was improved. A simple continuous SPE step was used to do the cleanup of the samples and the preconcentration of the analytes, prior to CE analysis. In this way, the developed method was suitable to separate four sulfonylureas in 16 min without the use of organic solvents in the buffer solution. The addition of SWCNTs to the buffer made possible the complete separation of the analytes and the resolution was improved. A simple continuous SPE step was used to do the cleanup of the samples and the preconcentration of the analytes, prior to CE analysis. - 113 %. In this way, the developed method was suitable to separate four sulfonylureas in 16 min without the use of organic solvents in the buffer solution. The addition of SWCNTs to the buffer made possible the complete separation of the analytes and the resolution was improved. A simple continuous SPE step was used to do the cleanup of the samples and the preconcentration of the analytes, prior to CE analysis. References *1+ Hin X. and Armstrong D.W., Acc. Chem. Res. 40 (2007) 1079¨C1086. *2+ Pandey, S., Anal. Chim. Acta 556 (2006) 38-45. *3+ Berthod, A., Ruiz-Angel, M.J., Carda-Broch, S., J. Chromatogr. A 1184 (2008) 6¨C18. *4+ Springer, V. H. and Lista, A.G., Talanta 83 (2010) 126-129. *4+ Springer, V. H. and Lista, A.G., Talanta 83 (2010) 126-129. *3+ Berthod, A., Ruiz-Angel, M.J., Carda-Broch, S., J. Chromatogr. A 1184 (2008) 6¨C18. *4+ Springer, V. H. and Lista, A.G., Talanta 83 (2010) 126-129. *4+ Springer, V. H. and Lista, A.G., Talanta 83 (2010) 126-129. *2+ Pandey, S., Anal. Chim. Acta 556 (2006) 38-45. *3+ Berthod, A., Ruiz-Angel, M.J., Carda-Broch, S., J. Chromatogr. A 1184 (2008) 6¨C18. *4+ Springer, V. H. and Lista, A.G., Talanta 83 (2010) 126-129. *4+ Springer, V. H. and Lista, A.G., Talanta 83 (2010) 126-129. *3+ Berthod, A., Ruiz-Angel, M.J., Carda-Broch, S., J. Chromatogr. A 1184 (2008) 6¨C18. *4+ Springer, V. H. and Lista, A.G., Talanta 83 (2010) 126-129. *4+ Springer, V. H. and Lista, A.G., Talanta 83 (2010) 126-129. + Hin X. and Armstrong D.W., Acc. Chem. Res. 40 (2007) 1079¨C1086. *2+ Pandey, S., Anal. Chim. Acta 556 (2006) 38-45. *3+ Berthod, A., Ruiz-Angel, M.J., Carda-Broch, S., J. Chromatogr. A 1184 (2008) 6¨C18. *4+ Springer, V. H. and Lista, A.G., Talanta 83 (2010) 126-129. *4+ Springer, V. H. and Lista, A.G., Talanta 83 (2010) 126-129. *3+ Berthod, A., Ruiz-Angel, M.J., Carda-Broch, S., J. Chromatogr. A 1184 (2008) 6¨C18. *4+ Springer, V. H. and Lista, A.G., Talanta 83 (2010) 126-129. *4+ Springer, V. H. and Lista, A.G., Talanta 83 (2010) 126-129. + Pandey, S., Anal. Chim. Acta 556 (2006) 38-45. *3+ Berthod, A., Ruiz-Angel, M.J., Carda-Broch, S., J. Chromatogr. A 1184 (2008) 6¨C18. *4+ Springer, V. H. and Lista, A.G., Talanta 83 (2010) 126-129. *4+ Springer, V. H. and Lista, A.G., Talanta 83 (2010) 126-129. -Angel, M.J., Carda-Broch, S., J. Chromatogr. A 1184 (2008) 6¨C18. *4+ Springer, V. H. and Lista, A.G., Talanta 83 (2010) 126-129.Talanta 83 (2010) 126-129. [5] Guan, Z., Huang Y., Wang, W., Anal. Chim. Acta 627 (2008) 225¨C231.Anal. Chim. Acta 627 (2008) 225¨C231.