Salt diffusion through 'non-porous' SC348
About a month ago, I posted some preliminary data that showed NaCl diffusion through SC348. This was motivated by my observation of vacuole formation on SC348. Since my hypothesis is that cell culture substrate permeability is the key factor for vacuole formation, cells shouldn’t have formed vacuoles on SC348. Unless it is actually porous. This was a little project that Nikita, a high school student, helped gather some data for.
SC348 TEM was marked by pore processing as 0% porosity:
To measure salt diffusion, 200mL DIH2O was added to a beaker, and the conductivity was measured to confirm no contaminating salts were present. Then, 0.6mL of 2M NaCl was added to the apical well of a round Sepcon. The water was mixed gently with a stir bar and conductivity measurements were taken for 24 hours. Three types of samples were tested: SC348, ‘regular’ Sepcons (SC195, SC144, SC501) and solid chips without membranes.
The top 3 curves are the ‘regular’ Sepcons. The middle 3 curves are SC348 and the solid chips didn’t allow any NaCl to pass. The expected equilibrium conductivity is ~ 700uS/cm. So, we have n=3 for each experimental group now, and the data show that salts pass SC348.