Method for sterilizing an assembly comprising at least one single-use device for biopharmaceutical fluid

A method for sterilizing by X-rays an assembly comprising a support and a single-use device for receiving a biopharmaceutical fluid, the density of the assembly being heterogeneous, the assembly having a height of 65% or more of a size of an X-ray radiation window, the height being considered according to a direction normal to the support, the single-use device comprising a sensor and a mixing device, the method comprising:

• placing a plurality of dosimeters distributed on and/or in the single-use device according to a predefined arrangement, one dosimeter being arranged on the sensor and/or on a port of the sensor, and another dosimeter being arranged on the mixing device,
• forming the assembly according to a predefined configuration by arranging the single-use device equipped with the plurality of dosimeters in a package on the support,
• repeating a passage of a first face of the assembly then a second face of the assembly in front of the X-ray radiation window, at several irradiation power-time pairs (PTi), by incrementing irradiation power-time pair between a minimum power-time pair (PTmin) and a maximum power-time pair (PTmax), followed by a mapping of an irradiation dose received by each of the plurality of dosimeters for each of the incremented irradiation power-time pairs;
• and
• determining an optimum X-ray radiation power-time pair (PTopt) for which the mapping reveals after passage of the first face and then the second face in front of the X-ray radiation window, all of the plurality of dosimeters record an irradiation dose above a minimum irradiation dose (Dmin) and that the dosimeter associated with the sensor records an irradiation dose below a maximum irradiation dose (Dmax), the minimum irradiation dose (Dmin) being defined as the dose from which sterility is effective, and the maximum irradiation dose (Dmax) being defined as being the irradiation dose at which the X-ray irradiation deteriorates the sensor.