The invention features the production of an amine-reactive proteoglycan, specifically chondroitin sulfate or hyaluronic acid. This material can be provided in powder (solid) or liquid form and combined with blood derivatives including serum, platelets, platelet rich plasma, bone marrow, or with other tissue products to form hydrogels. The properties (physical and biological) are different for each of these hydrogels and can be further manipulated by controlling the conditions under which the hydrogels are formed. Such properties include the biodegradability of the hydrogel, the compressibility, the adhesive strength, the presence of pharmaceutical agents or therapeutic cells, and resiliency.
