Correction to: J Nanobiotechnol (2019) 17:90 https://doi.org/10.1186/s12951-019-0524-9

After publication of this article [1], an error was found in the description of the holmium isotopes. 165Ho is a stable isotope a fraction of which is activated to 166Ho by neutron activation in a nuclear reactor [2]. In one paragraph of the published article, describing holmium containing QuiremSpheres, 165Ho should be replaced with 166Ho. The correct description is given below:

“QuiremSpheres are poly-l-lactic acid based microspheres, containing 166Ho. The size of the particles varies from 15 to 60 μm and the use of poly-l-lactic acid allows to achieve the particle density of 1.4 g/cm3, which is closer to the density of blood (1.06 g/cm3). The 165Ho is activated to 166Ho with neutron activation in a nuclear reactor. Due to the short half-life period of 166Ho, each patient dose of QuiremSpheres needs to be prepared separately, thus, a specific activity can differ in each dose and depends on the needs of a patient.”