Hi David!

I have a similar problem. It seems iodixanol and heavy water are fine but if you cells are non-adherent I think there going to float and be exposed to air which is quite bad for them,

Regards,

Hi David,

the most common aqueous solutions for that purpose are using iodixanol, glycerol or heavy water as a solute. The available density ranges are 1000-1266g/cm^3 for iodixanol, 1000-1260g/cm^3 for glycerol, and 1000-1100g/cm^3 for heavy water. Glycerol has a relatively high impact on viscosity. If thats a problem and 1100g/cm^3 is enough I would suggest using heavy water because it doesn't really affect the physical properties of the solution.

Glycerol is the least expensive. I wrote an article about the density of its aqueous solutions with an open matlab script to calculate it: Article Density model for aqueous glycerol solutions

For iodixanol there is much less literature published. I guess that the following publication could help:

https://www.nature.com/articles/ncomms11556

If you want to use heavy water, there is some literature about the density of its solutions. For example

https://inis.iaea.org/search/search.aspx?orig_q=RN:14730979

Regards,

Andreas Volk