Preparation of lipid based nanoparticles comprising homogenizing a lipid component with an aqueous component and/or forming compounds into prefabricated lipid based nano-particles in a dual asymmetrical centrifuge, is new. Independent claims are also included for: (1) the lipid based nano-particle (preferably liposome), prepared by the above method, comprising sensitive or short-lived substances, which are preferably short-lived diagnostic and hydrolysis-sensitive active substances, particularly cytostatic; (2) a mixing apparatus, for chemical and/or biological substances (preferably for the above method), comprising a first driving device for rotating an arm around a first axis of rotation, a mixing container connected with the arm in a distance to the first axis of rotation for the addition of the substances and a second driving device for rotating the mixing container around second axis of rotation passing by the mixing container, where the inner walls of the mixing container exhibits different distances to the second axis of rotation; (3) a mixing container, for a dual asymmetrical centrifuge, particularly for the execution of the above method, comprising a first transmitting room for adding a first substance and a second transmitting room for adding a second substance, where an opening is provided in a partition between the transmitting rooms, in order to enable the transferring of the substances into the other transmitting room with increase in the centrifugal force; and (4) a kit, for executing the above method, comprising lipid component(s), optionally an aqueous component or the non-aqueous components of the aqueous component and/or their premix; prefabricated lipid based nano-particles; and/or the mixing container.