Abstract
Ethylene glycol oligomers were visualized by indirect conductimetric detection based on dilution of the mobile phase due to the analytes. A high electrical conductivity background was maintained by the addition of 5 mM sodium nitrate in the mobile phase, and the analytes were visualized by decreases in the background when they eluted. A capacitively coupled contactless conductivity detector was convenient to monitor effluents from the microcolumn with minimum extra-column band broadening. The signals as negative peaks were linear to the concentration of the analytes, and a concentration detection limit of 0.025% was achieved for tetraethylene glycol at S/N=3, corresponding to the mass detection limit of 38 ng for 0.15 μl injection. The logarithm of the retention factor of ethylene glycol oligomers was linear to the degree of polymerization (DP) as well as to the acetonitrile composition in the mobile phase. These situations allowed us to estimate the DP of eluted ethylene glycol oligomers by using a few oligomers with known DP. The dynamic reserve, defined as the ratio of the background to its noise level achieved under the present conditions, was 2.3 × 105 which was much larger than that achieved by UV absorption detection. The present method was applied to profile ethylene glycol oligomers contained in commercially available PEG reagents.
Similar content being viewed by others
References
H. Small and T. E. Miller, Jr., Anal. Chem., 1982, 54, 462.
K. Hayakawa and A. Yamamoto, Bunseki Kagaku, 1995, 44, 417.
T. Takeuchi, Bunseki Kagaku, 2000, 49, 649.
T. Takeuchi, S. Watanabe, K. Murase, and D. Ishii, Chromatographia, 1988, 25, 107.
S. I. Mho and E. S. Yeung, Anal. Chem., 1985, 57, 2253.
T. Takeuchi and T. Miwa, Chromatographia, 1993, 37, 281.
K. Tanaka and J. S. Fritz, J. Chromatogr., 1987, 409, 271.
S. Ichikawa and H. Miyata, Bunseki Kagaku, 2007, 56, 751.
A. J. Zemann, E. Schnell, D. Volgger, and G. K. Bonn, Anal. Chem., 1988, 70, 563.
J. A. F. da Silva and C. L. do Lago, Anal. Chem., 1998, 70, 4339.
P. Kubáň and P. C. Hause, Anal. Chim. Acta, 2008, 607, 15.
T. Takeuchi and D. Ishii, J. Chromatogr., 1981, 213, 25.
T. Takeuchi and D. Ishii, J. Chromatogr., 1987, 393, 419.
T. Takeuchi and D. Ishii, J. Chromatogr., 1987, 403, 324.
L. Huang, P. C. Gough, and M. R. DeFelippis, Anal. Chem., 2009, 81, 567.
E. R. Kaal, M. Kurano, M. Geissler, and H.-G. Janssen, J. Chromatogr., A, 2008, 1186, 222.
P. Jandera, J. Fischer, H. Lahovska, K. Novotna, P. Cesla, and L. Kolarova, J. Chromatogr., A, 2006, 1119, 3.
B. Trathnigg, A. Gorbunov, and A. Skvortsov, J. Chromatogr., A, 2000, 890, 195.
Y. Lv, S. Zhang, G. Liu, M. Huang, and X. Zhang, Anal. Chem., 2005, 77, 1518.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Takeuchi, T., Sedyohutomo, A. & Lim, L.W. Indirect Detection of Ethylene Glycol Oligomers Using a Contactless Conductivity Detector in Capillary Liquid Chromatography. ANAL. SCI. 25, 851–854 (2009). https://doi.org/10.2116/analsci.25.851
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.2116/analsci.25.851