The third paragraph of the Pharmaceutics’ article references Dr. Mills’ research from 40 years ago.
The physical phenomenon known as the “Mössbauer effect” (Mössbauer resonant absorption), has been used as a powerful research tool in many areas of research [12] including biomedicine [13,14]. The use of the secondary radiation emitted by a 57Fe nucleus excited by a 57Co source was already considered a viable option for cancer treatment (Randell L. Mills, US48154476) but it remains unexplored as a targeted radiation modality. In relation to cancer therapy, very few studies have been reported since the pioneering work of R. L. Mills et al. more than 40 years ago [15]. The authors reported the elegant concept of this type of radiation in HTB26 and MCF-7 breast cancer cells after the administration of 57Fe(III) bleomycin. Irradiation with resonant Mössbauer gamma-rays (14.41 keV) induced cell death, presumably by Auger cascade and secondary radiation, with extremely small radiation doses (~10−5 Gy), which are about 100,000 times lower than those necessary to achieve a similar effect with conventional gamma rays. This form of radiotherapy represents a method of increasing the radiosensitivity of tumors through selective energy deposition in cancer cells. A previous study revealed that the Mössbauer effect, when combined with 57Fe-enriched boron clusters, could be a promising radiation modality for glioblastoma treatment [16]