Method, apparatus and marking substance kit for multi-parameter x-ray fluorescence imaging

A method for multi-parameter X-ray fluorescence imaging of a biological/living sample (10) containing a first labelling substance with maximum detection sensitivity and minimum radiation dose, comprising the steps of: irradiating the sample (10) with X-ray radiation (1) wherein X-ray fluorescence (2) of the first labelling substance is excited; performing spatial resolution detection on X-ray fluorescence 2 of the first labeled substance; and determining a distribution of the first labeling substance in the sample (10) on the basis of the X-ray fluorescence (2) of the first labeling substance, the sample (10) comprising at least one further labeling substance excited by the X-ray radiation (1) into the X-ray fluorescence (2), the fluorescence lines (3) of the first labeling substance and of the at least one further labeling substance being different, and the distribution of the first labeling substance in the sample (10) being determined on the basis of the X-ray fluorescence (2) of the first labeling substance. At least one of the first labeling substance and the at least one further labeling substance is coupled to active ingredient molecules and/or ligand molecules which are provided for specific interaction with the sample (10) or are contained in cells, in order to be able to track these molecules, the detection comprises a spectrally resolved detection of the X-ray fluorescence (2) of the first labeling substance and of the at least one further labeling substance, in addition, at least one distribution of the at least one further labeling substance in the sample (10) is determined from the detected X-ray fluorescence (2) of the first labeling substance and of the at least one further labeling substance. An imaging device (100) for multi-parameter X-ray fluorescence imaging and an optimized selection method of a labeling substance kit for introducing a labeling substance into a sample (10) are also described.