Resumen:
his work describes the polyelectrolyte complexation between polyquaternium cellulose
(PQ-10) and chondroitin 4-sulfate (C-4S), an important structural component of cartilages.
The complex shows different behaviors with increasing concentrations of the polyanion.
Initially, PQ-10/C-4S interaction forms a soluble, translucent hydrogel that reaches maximum
viscosity at a sulfate carboxylate/quaternary ammonium molar ratio lower than 1.
After that, the complex begins to aggregate until complete precipitation, and finally, at
higher concentrations of C-4S, the resuspension of the aggregate is observed. Further addition
of PQ-10 initiates new cycles of precipitation/resuspension for at least seven times.
C-4S contains sulfates and carboxylates able to interact with quaternary ammonium of
PQ-10. The results of a comparative study with polymers containing only carboxylate or
sulfate to evaluate the influence of each group suggest that the phenomena observed
involved, essentially, c