Use of biocompatible phosphazene polymers (I) to prepare substrates for growing cells. Use of biocompatible phosphazene polymers of formula (I). [Image] n : 2 to infinity R 1>-R 6>same or different alkoxy, alkylsulfonyl, dialkylamino or aryloxy, or a nitrogen-containing heterocycloalkyl or heteroaryl. Independent claims are also included for the following: (a) substrate for growing cells, prepared from (I) (b) carrier for growing cells, coated with (I) (c) method for preparing substrates and carriers of (a) or (b) and (d) implant consisting of a support structure of (I) and cells growing artificially on it.
