User:James C. Schwabacher/Notebook/Protein-Templated Quantum Dots/2014/09/24

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Objective Complete the QD synthesis begun yesterday Continue precipitation of JCS 1 and JCS 2 Begin precipitation of JCS 3 Protocol Create 20 mM sodium sulfide solution .024018 g of Sodium Sulfide (MW=240.18) needed for 5 mL Used .1373 g of Sodium Sulfide used (in 5 mL) because the sample is contaminated with excess water Add 4 mL of 20 mM sodium sulfide solution to reaction Allowed the mixture to stir vigorously for 15 minutes Poured contents (minus the stir bar) into a darkened falcon tube and filled with 200 proof ethanol to the 50 mL mark. The falcon tube was left in the freezer to begin precipitation. total synthesis time: 13 hrs (including 15 minutes for Sodium Sulfide addition) Removed 1 mL aliquot from JCS 3 (before adding ethanol) for future testing with UVVIS and Fluorescence Precipitation of JCS 1 and 2 Falcon tubes spun at 4000 RPM for 15 minutes Solvent was decanted and stored while the dark precipitate was re-suspended in ~15 mL of distilled water. Solutions were stored in the dark at room temp for future analysis with UVVIS and fluorescence. Notes JCS 1 remained mostly clear with minimal dark precipitate, as it was before it was spun. JCS 2 remained darkened brown. After spinning some precipitate was visible Eleni and I feel that the next step is to try centrifugation at very high speeds, which was necessary with some of the Mg:ZnS quantum dots we created last semester.