Resonant cancer theranostics

Objectives By taking advantage of resonant absorption complexes in heavy-element-tagged nanoparticles or contrast agents delivered to disease sites, we can use tunable, narrow energy bands for both diagnosis and therapy to minimize radiation exposure to neighboring tissue.

Methods An electron beam ion trap (EBIT) developed for atomic and plasma physics investigations serves as the source of tunable, monochromatic X-rays for imaging and therapy. A cryogenic x-ray microcalorimeter developed for spectroscopic studies of laboratory and astrophysical plasmas makes the spectroscopic images. It is used to tune the X-ray emission from the EBIT plasma to the band of resonant absorption edges in the tagged nanoparticles. It can identify line emission with less than 20 counts per energy resolution element making the eventual dose for diagnostic imaging extremely low.

Results The EBIT and the microcalorimeter are described with emphasis on the hard X-ray energy range required by cancer theranostics. Fingerprints of heavy-element uptake in tagged malignant tissue will be presented.

Conclusions The electron beam ion trap is a smart x-ray source capable of generating monoenergetic resonant X-rays that maximally interact with the matching high-Z contrast agent or nanoparticles; the spectroscopic microcalorimeter is a “zero-background detector” and can discriminate resonant signatures with 10 times better resolution than any other X-ray spectrometer, thus providing very high sensitivity and specificity.