Journal of Student Research 2017

138 Journal Student Research Difference in the Final Product Absorbance Spectra

Because final organic product formation occurs in solution via radical decomposition, it is possible that changing the concentration of dye or radical intermediate would change product composition. Differences in product composition with absorption in the visible range would become apparent by comparison of the final optical spectra for reactions. The difference spectrum of the 600 s spectra for low and high enzyme concentration and dye concentration are shown in Figure 7 and 8, respectively. With the exception of more product formation at 350 nm, as expected, the spectra show no major differences caused by changes in concentrations in dye or enzyme. This indicates that the substrate radical follows a single major decomposition route to form the final product. Figure 7.

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Figure 7. Difference in absorbance between 0.497 nM and 7.948 nM enzyme concentrations at 600 seconds. Difference in absorbance as a function of wavelength for the 0.50 nM enzyme concentration versus the 7.9 nM enzyme concentration at 600 seconds as described in methods. 600 seconds is last recorded data time in the reaction. Figure 8.

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