How Boron Neutron Capture Therapy works
BNCT combines two innocuous components: the isotope boron10 and neutrons. The BNCT therapy operates through the highly selective delivery of boron to tumor tissues.
First, the boron isotopes are injected into the patient. Given a sufficient amount of time, which generally requires several hours, the blood and healthy tissues become free of boron.
The beam port door adjacent to the MU Research Reactor core is opened, and the patient is loaded onto a hydraulic lift in the neutron beam chamber. The hydraulic lift lowers and precisely aligns the patient with the neutron beam line, a tube connected to the reactor core. The beam port door is closed to protect the technicians. The core of the nuclear reactor produces a wide spectrum of neutron energies and intense gamma radiation.
The neutron beam tube is constructed from exotic filters that act like nuclear sunglasses. These filters slow down the fast neutrons and remove nearly all of the gamma radiation. The beam line filters allow only clean, slow moving neutrons to pass.
The tumor is then irradiated with the cooled, filtered neutrons. Boron10 atoms, which are now inside tumor cells, capture the neutrons in fission to produce a helium nucleus, or alpha particle, and a lithium nucleus. These fast-moving particles possess 2.4 million electron volts of kinetic energy, and they deposit this energy over a very short distance, about five micrometers, or a single cell diameter. In effect, the BNCT reaction produces a nuclear explosion fully contained in the space of a single cell. In a fraction of a second, the cancer cell is destroyed and all radiation completely disappears.
The neutron irradiation requires approximately 20 minutes. After this is complete, the beam port door is opened, and the lift raises the patient out of the facility.
The beam port facility took 18 months to construct, and is expected to be used for experiments using mice beginning in January, said John Brockman, an assistant research professor. If the research proves successful and moves to clinical trials, MU could eventually build a larger beam port facility that would accommodate human treatments, Bockman said.
Source: University of Missouri