This invention relates magnetosomes for use in a laser radiation medical treatment, wherein the magnetosomes are administered to a body part of an individual and:- In a first step, the magnetosomes are irradiated by a laser radiation, and- In a second step, the magnetosomes are irradiated by a laser radiation of lower power than in the first step or no laser i rradi ati on of the magnetosomes is performed, andthe sequence of the first step and second step is repeated at least once.