Recently I have performed a diffusion experiment with a dialysis membrane containing methylene blue. A schematic picture of the experiment:
I want to calculate the flux (amount diffused/area*time) from the samples I have taken. However I am stuck with how to calculate the surface area of the dialysis bag so I can use Fick's law to estimate the flux. The dialysis bag is cylindrical, however when you put the 2 pins above to close it, it is not completely cylindrical anymore as you can see in the picture. Anyone that could help me out with this? If in need of membrane specifications I can post them.