Summary
Solubilities of polar analytes in supercritical CO2 can be enhanced by the addition of polar modifiers. The addition of modifier into an SFC system using a low cost reciprocating pump has been studied. Two different mixing chambers were evaluated for mixing the supercritical CO2 with modifier. It appeared that a mixing chamber with a packed bed was enough to reduce baseline noise from the modifier pump. Results from the effect of pressure and temperature with various modifier flow rates were obtained. High percentages of modifier (>15%) at a low CO2 pressure (2000 psi) caused baseline instability. In addition, different I.D. columns were tested with the system and the effect of modifier compressiblity on detector noise was also studied. Several pharmaceutical compounds were separated to demonstrate system performance.
Similar content being viewed by others
References
M. Ashraf-Khorassani, S. Shah, L. T. Taylor, Anal. Chem.62, 1173 (1990).
D. R. Gere, R. Board, D. McManigill, Anal. Chem.54, 736 (1984).
M. Ashraf-Khorassani, L. T. Taylor, Elution behavior of nitrogen-containing compounds of different basicity from various stationary phases employing supercritical mobile phases, in “modern supercritical fluid chromatography”, C. M. White, Ed., Hüthig Verlag, Heidelberg, Germany, 1988, Ch. 7.
T. A. Berger, J. F. Dye, Unpublished results.
J. M. Levy, W. M. Ritchey, J. Chromatogr. Sci.24, 242 (1986).
T. A. Berger, J. F. Dye, J. Chromatogr. Sci.29, 390 (1991).
T. A. Berger, J. F. Dye, M. Ashraf-Khorassani, L. T. Taylor, J. Chromatogr. Sci.27, 105 (1989).
M. Ashraf-Khorassani, M. Fessehaie, L. T. Taylor, T. A. Berger, J. F. Dye, J. HRC11, 352 (1988).
T. A. Berger, J. F. Dye, J. Chromatogr. Sci.29, 310 (1991).
T. A. Berger, J. F. Dye, J. Chromatogr. Sci.29, 26 (1991).
T. A. Berger, J. F. Dye., J. Chromatogr. Sci.29, 54 (1991).
T. A. Berger, J. F. Dye, J. Chromatogr. Sci.29, 141 (1991).
T. A. Berger, J. F. Dye, J. Chromatogr. Sci.547, 377 (1991).
M. Lee, K. E. Markides, “Analytical supercritical fluid chromatography and extraction. Chromatography Conference Inc. 1991.
J. Via, L. T. Taylor, F. K. Schweighardt, Anal. Chem.66, 1459 (1994).
Lee Company catalogue.
“CRC Handbook of Chemistry and Physics”, CRC prss, 54th edition, F-12.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Ashraf-Khorassani, M., Levy, J.M. Addition of modifier in supercritical fluid chromatography using a microbore reciprocating pump. Chromatographia 40, 78–84 (1995). https://doi.org/10.1007/BF02274611
Received:
Revised:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF02274611