Boron is a hard, brittle semimetal. It is lustrous black in crystalline form and brown in amorphous form. It combines with oxygen to form boron oxide (B2O3), boric acid (BHB) and other boride compounds. It is also used in pyrotechnic devices to produce a green flame and borosilicate glass. It is a useful neutron absorber in nuclear reactors. It is present in the form of borosilicate rods in pressurized water reactors for reactivity control and in sodium pentaborate for standby liquid control systems in boiling water reactors. It is also used as a chemical shim in fast breeder reactors and as a radiation shield.
In humans, the isotope boron 10 (B-10), which has a high thermal neutron capture cross section, can be used in so-called boron neutron capture therapy (BNCT). When injected into cancer cells, B-10 atoms absorb the slow neutrons from outside the body, releasing alpha particles that destroy the cell.
However, it is difficult to deliver enough boron 10 to cancer cells in a concentrated manner for this treatment to be practical. Furthermore, boron contamination is often an issue in B-10 doping in commercial-off-the-shelf (COTS) silicon microcontrollers due to its high neutron capture cross section. Therefore, it is critical to understand the kinetics of boron insertion into the dative carbene boron-boron bond and to accurately measure the concentration in cell cultures using techniques like secondary ion mass spectrometry (SIMS) and laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS). This paper describes the optimization of sample preparation for these two analytical methods on a variety of cell culture samples.