This is just a quick post and may not be relevant to anyone in the cosmos but I had several TEMs of dental alginate (in this case it was Kromopan) that were made when I was trying to figure out a way to quanatify gingival overgrowth in mice.  I am not sure that a way was found but we tested several alginates to see which one gave the best tooth “footprint”, gum, and  bone delineation. This was just a fun gemish.  I dont know if i will spend the time to look up the structure and compare what i saw to what is known about the alginate.  But this is an artsie-craftsie version of the original TEM (lower right). Fixed in buffered aldehydes three days after molding in mouse jaw, and routine processing for TEM. Bar marker=1 micron.