Procedure 8.4 Luminescence Studies of

Solution Preparation Note clean glassware and cuvettes thoroughly before using. Interference from impurities can lead to a tremendous waste of time and money. Wash cuvettes with soap, de-ionized water and wash acetone, and rinse with spectroscopic-grade MeOH. Keep your work area clean Impurities that fluoresce or that quench fluorescence are the bane of fluorescence spectroscopy. 

The molar absorptivity at 354 nm for [Cr(phen)3]3+ is g354 = 4200 M 1 cm-1. Determine the precise concentration of your stock solution by UV-visible analysis. 

Prepare 10 ml of a 2.4 x 10-4 M guanosine (MM = 283.2 g mol ) stock solution. The mixtures of guanosine in water may require sonication to dissolve the solid. 

Prepare a solution having [G] the same as the last in your series, but with no chromium complex. This will serve as a control sample. 

Prepare reaction solutions according to Table 8.2 in 4 dram sample vials with screw caps. 

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