Synthetic polymers fulfill many functions in biotechnology and medicine. In cell culture technology and tissue engineering they provide the surfaces to which cells may attach. Cross-linked polymer networks are used for drug delivery and cell encapsulation. Polymer-based porous membranes can be used to shield implanted cells from the immune system of the host, while allowing for the exchange of nutrients and metabolic waste products thus keeping the cells alive and functioning. In genetic engineering, polymers often play a very important role during the transfer of the foreign genetic material into the recipient cell. In this context polymers present interesting and perhaps safer alternatives to gene delivery by viruses. Last.
