A method for automatically dosing a fixative solution in a flexible bag containing at least one biological organic sample comprises placing the bag with the sample in a dosing system (e.g., on a holder or weighing device), computing a required volume or weight of fixative solution as a function of the sample or the bag with the sample, and automatically transferring the computed volume or weight of fixative solution from a storage container into the bag. A system is also described for automatically dosing a fixative solution in a flexible bag containing at least one biological organic sample, a carrier for said flexible bags, and a storage cabinet for storing the carrier.
