Effect of negative ion-interaction reagent and pH on the HPLC separation of preservatives

CHED 240

Danielle Schwartzenburg1, Raisa Nguyen, nguyenrd@stthom.edu2, and John A. Palasota, japalaso@stthom.edu2. (1) Department of Chemistry, University of St. Thomas, 3800 Montrose Boulevard, Houston, TX 77006, (2) Department of Chemistry & Physics, University of St. Thomas, 3800 Montrose Boulevard, Houston, TX 77006
A reversed-phase HPLC method is described that allows the separation and simultaneous determination of benzoic acid, 4-hydroxybenzoic acid, and ethyl paraben. Mobile phase pH and concentration of 1-octanesulfonic acid sodium salt (negative ion-interaction reagent) in the mobile phase appear to affect the separation individually, with changes in pH having a greater affect on the separation. This is supported by statistical modeling of the chromatographic data.
 

Undergraduate Research Poster Session: Analytical Chemistry
11:00 AM-1:00 PM, Monday, April 7, 2008 Morial Convention Center -- Hall A, Poster

Division of Chemical Education

The 235th ACS National Meeting, New Orleans, LA, April 6-10, 2008