Stabilization of soft gels

Hello,
I am a Stem Cell Scientist with little background in biomaterials.
I have a question on gelation of soft gel-like materials.
I have been trying to create a stable gel with a viscous protein material secreted by cells.
While the protein adheres to tissue culture plastic, it rapidly re-solubilizes. I am sure the protein mixture has a number of extracellular matrix proteins in it with gelation capabilities.

My question is: does an expert know about crosslinkers, gelling agents or adjusting the pH/ionic strength that could create a stable gel for my protein mixture without disrupting the protein composition?

Thanks..