PAAm/CA Crosslinked Hydrogels - Subdermal Application in Rats

Polyacrylamide (PAAm) and cellulose acetate (CA) forms a polymeric networkinterpenetrated by a free radical mechanism with or without the addition of a crosslinking agent, N,N'-methylene bisacrylamide (NMBA). The swelling and the compression modulus depend on the amount of CA, the higher the amount of CA the lower the swelling and the higher the compression modulus. The swelling and compression modulus of different hydrogel mixtures were measured. Subsequently, they were implanted in Wistar rats and during a period of 7 weeks, the compression modulus of the implants were measured at 15 and 20% in mass with NMBA or without NMBA, which are modified when in contact with living tissue.