Abstract
Stir bar sorptive extraction (SBSE) is a relatively new technique which employs an adsorptive coating on a magnetic stir bar. The technique is similar to solid phase microextraction (SPME) in theory, but in practice is considerably different due to the difference in physical design. Three experiments were conducted to explore aspects of using SBSE for food analysis. First is a basic examination of calibration curves using SBSE versus SPME. SBSE behaved similarly to SPME in terms of accuracy and precision. The best results were obtained by one stir bar to sample each calibrating solution instead of using the same stir bar to sample all of the calibration solutions. Second, the viability of using SBSE to simplify long distance collaboration was examined by exposing six SBSEs to pineapple juice and analyzing three immediately and then another three 24 hours later to simulate over night shipping of the stir bars. Qualitatively, the chromatograms were identical, and quantitatively, only two of the twenty peaks examined were statistically significantly different. Lastly, the possibility of inserting the stir bars inside of immature fruit, allowing the fruit to grow around the stir bar, extracting the stir bar, and determining fruit maturity markers was examined. This sampling method was found to be not practical due to the lack of mobility of compounds inside fruit and the resulting chromatogram intensities were too weak for normal analysis with only methyl tridecanoate exhibiting any correlation with ripening (r = -0.8 for both 'Bartlett' and 'D'Anjou' varieties).
