User:Moira M. Esson/Notebook/CHEM-581/2012/10/24

Objectives

1. Prepare porphyrin films
2. Add salts to porphyrin film solution(preparation to measure UV-vis)
3. Dilute Cu²⁺ exchange with films prepared on 2012/10/17 to use for AA

General Notes

The propyhrin film crosslinked last time lost all color. Appears as if not porphyrin remains on the film. Need to use UV-vis to confirm

Film preparation

All films followed the general protocol of glutaraldehye and porphyrine film preparation. Films containing additional HCl had two drops of HCl added to the reaction mixture and were allowed to stir until the reaction mixture was a uniform green color. HCl was added after both glutaraldehyde and porphyrine

• Addition of HCl may cause the reaction mixture to coagulate. When pouring the mixture, if coagulation has occurred, move coagulated portion to the side of the Teflon dish.

Prepared Films

1. PVOH(MW 22,000) 1.0067g+1mL GA+1mL porphyrine+ 2 drops HCl
2. PVOH(MW 22,000) 1.02114g+0.5mL GA+ 1mL porphyrine+ 2 drops HCl
3. PVOH(MW 22,000) 1.0073g+1.0mL GA+ 1mL porphyrine
4. PVOH(MW 22,000) 1.05225g+ 1mL porphyrine

Observations:

• Films with HCl added turned a dark greenish color
• Films without HCl were a pinkish color(mixed. not a uniform color throughout)

UV-vis

• Stock solutions of 10mM Al₂(SO₄)₃, 100mM Fe₂(SO₄)₃ and 100mM Na₂SO₄ were prepared by Melissa Novy using HPLC grade H₂O and were combined with 944.5nM porphyrine solution
• Following solutions were run on the UV-vis.

Obtained UV-vis spectra: