Mi precious negatives from late 90s / early 2000s have developed nasty spider-like structures due to (I believe) mold. Some online research suggests to wipe them gently with 99% isopropyl alcohol.
I believe this not only will get rid of the mold, but it also might dilute other chemicals in the emulsion, namely the stabilizer added at the end of the C-41 development process to pre 2000s Kodak color film.
Hence with the isopropanol rubbing I might get rid of the mold and have a time window to digitize the film but then, in a matter of months or few years, the colors in the film will fade away irreversibly.
Do I need to apply a stabilizer (formaldehyde or something similar, I read) to my photographic negatives after cleaning them with isopropanol? If so, how?