The present invention relates to a process for the preparation of films of conductive polymers, by the technique so-called roll-to-roll, which allows to obtain free¬ standing films having advantageous features such as toughness, flexibility, ability to adhere to different substrates, a submicron thickness and a very high ratio surface area/thickness; the present films are suitable for use in several technological applications, in particular for the development of biosensors, and in the production of flexible electronic components with large surface, suitable for wearable devices and also intended for contacting skin.