a method for manufacturing of ultrahigh molecular weight polyethylene for implants , where the implants have been machined out of uhmwpe blocks or extruded rods , has anthocyanin dispersely imbedded in the polyethylene . the implant is then exposed to γ ray or electron beam irradiation in an amount of at least 2 . 5 mrad followed by a heat treatment to prevent the implant from becoming brittle in the long term as well as to improve strength and wear . the method includes mixing a powder or granulate resin of uhmwpe with an aqueous liquid that contains anthocyanin in a predetermined amount . the water is evaporated in order to deposit the anthocyanin in a predetermined concentration on the polyethylene particles . the doped uhmwpe particles are compressed into blocks at temperatures in a range of approximately 135 ° c .- 250 ° c . and pressures in a range of approximately 2 - 70 mpa . medical implants are made from the blocks .