I finally figured out how to calculate the quantum yield of my samples, so I used a known reference from the Oregon medical laser center (fluorescein in ethanol) and compared it to my new buffer solution of KBr (potassium bromide.)

Then I compared a sample of fluorescein I had done on May 3rd (fluorescein in ethanol) to the laser center's sample to get a more accurate quantum yield value.

http://publiclab.org/notes/dhaffnersr/05-07-2016/quantum-yield-calculations-for-fluorescein-in-potassium-bromide