Objectives
- Standardize sodium bicarbonate solution
- Run UV-vis on porphyrin films
- Test swelling on all crosslinked glutaraldehyde films
- Test the time necessary to facilitate a color change in various porphyrin using Fe2(SO4)3 solution, Al2(SO4)3 solution and Na2SO4.
- Run UV-vis on color changed porphyrin films
UV-vis porhyrin films
General protocol for UV-vis on porphyrin films:
- Remove crosslinked porphyrin films from deionized H2O and pat dry using a paper towel
- Using a quartz cuvette as a guide, cut a strip of paper the same width as the quartz cuvette.
- Using the strip of paper as a guide and scissors(or a similar sharp instrument) carefully cut the porphyrin film the same width as the paper reference. When cutting the film, try and use a smooth portion of film.
- Measure the thickness of the film. This will be used as the pathlength.
- Using forceps, carefully place the cut strip of film in a clean quartz cuvette.
- Using a spatula, gently press the film against the cuvette.
- Carefully place the cuvette into the Shimadzu 2550 spectrophotometer.
- Measure following the general protocol for UV-vis measurements
Porphyrin film UV-vis pathlengths:
Film measured
|
Thickness of film(mm)
|
2.4394g PVOH(22K)+0.5mLGA+0.99mL porphyrin prepared 10/19 |
0.77
|
PVOH(22K) 1.0073+1.0mL GA+1mL porphyrin prepared 10/24 |
0.79
|
PVOH(22K) 1.02114g+0.5mL GA+1mL porphyrin prepared 10/26 |
1.01
|
PVOH(22K) 1.0067g+1mL GA+1mL porphyrin |
1.27
|
PVOH(22K) 1.05225g+ 0.5mL GA+1mL porphyrin prepared 10/24 |
0.8
|
Standardization of sodium bicarbonate
New weights of PHP used:
Trial number
|
Mass PHP(g)
|
1 |
1.13465
|
2 |
1.13423
|
3 |
1.13518
|
Titration information:
- The general protocol for titrations was used. The sodium bicarbonate solution prepared2012/11/09 was used as the base. Three drops of bromothymol blue was added each PHP solution.
Trial number
|
Initial Volume (mL)
|
Final volume (mL)
|
Total volume used(mL)
|
1 |
2.3 |
10.2 |
7.9
|
2 |
10.2 |
19.2 |
9
|
3 |
19.2 |
29 |
9.8
|
Swelling for GA films
General Protocol for film swelling:
- Cut small piece of crosslinked glutaraldehyde films and place in small beaker. Allow to completely dry for ~48 hours
- Weigh small piece of film. Record mass.
- Place dry piece of film in 10mL beaker and add 10mL HPLC grade H2O to completely cover the film. Parafilm the beaker and allow to sit for three days.
- Reweigh the film. Record the mass.
Please refer to Melissa Novy's lab notebook for swelling information.
- Note: Small pieces of film used for FTIR measurement were used for swelling information.
Color Change of porphyrin films
|