Oxybenzone Oxidation

The oxidation of oxybenzone was attempted with a reaction of oxybenzone, hydrogen peroxide, and horseradish peroxidase.

Making the Samples For Enzymatic Oxidation

Our actual samples to be tested required the making of a 2 mM oxybenzone pH 5 buffer stock solution, a hydrogen peroxide stock solution, and a horseradish peroxidase solution.

2 mM Oxybenzone Buffer Stock Solution

Combined 50 mL of dioxane, 50 mL of pH 5 buffer solution, and 45.7 mg of oxybenzone in a bottle. Added the oxybenzone to the dioxane, and then added the buffer solution.

Hydrogen Peroxide Stock Solution

Measured 5 mL of water into a scintillation vial. Added 283 microliters of 30% hydrogen peroxide to the water. This provided a hydrogen peroxide solution of about 0.413 M.

Horseradish Peroxidase Stock Solution

Preparing the Final Samples

Measured out 5 mL of the 2 mM oxybenzone buffer stock solution into 4 different scintillation vials. Added hydrogen peroxide solution in different amounts to each vial (6 microliters, 12 microliters, 18 microliters, and 24 microliters). Add 10 microliters of horseradish peroxidase solution to each vial.

Unfortunately, our enzymatic oxidation was unsuccessful, so our focus turned to chemical oxidation.

Making the Samples For Chemical Oxidation

2 mM Oxybenzone Buffer Stock Solution

Combined 50 mL of dioxane, 50 mL of pH 5 buffer solution, and 45.7 mg of oxybenzone in a bottle. Added the oxybenzone to the dioxane, and then added the buffer solution.

Potassium Permanganate Stock Solution

Preparing the final samples

Measured out 5 mL of the 2 mM oxybenzone buffer stock solution into 4 different scintillation vials. Added potassium permanganate solution in increasing concentrations to each vial (6 microliters, 12 microliters, 18 microliters, and 24 microliters).

Data

Figure 1. Graph of oxybenzone dissolved in methanol.

Figure 2. Graph of the samples tested with hydrogen peroxide (6 ul) catalyzed by horseradish peroxidase.