Polymer-Stabilized Elemental Boron Nanoparticles for Boron Neutron Capture Therapy: Initial Irradiation Experiments

Area of Science:

• Nanomedicine
• Nuclear Medicine
• Oncology

Background:

• Boron neutron capture therapy (BNCT) requires high boron-10 (¹⁰B) isotope accumulation in tumor cells.
• The current drug, borophenylalanine (BPA), has limitations in maintaining sufficient boron concentration during irradiation.
• Development of novel boron delivery agents is crucial for effective BNCT.

Purpose of the Study:

• To synthesize and evaluate elemental boron nanoparticles (eBNPs) stabilized with hydroxyethylcellulose (HEC) as a potential new drug for BNCT.
• To assess the efficacy of eBNPs in reducing glioma cell viability during BNCT compared to BPA.

Main Methods:

• eBNPs were synthesized using ultrasonic dispersion and stabilized with HEC.
• Human glioma cell lines (U251, U87, T98G) were incubated with eBNPs or BPA (40 µg ¹⁰B/mL for 24 h).
• Cells were irradiated using an accelerator-based neutron source, and cell survival was assessed using colony formation assays and the linear-quadratic model.

Main Results:

• HEC-stabilized eBNPs showed no cytotoxicity to glioma cells without neutron irradiation.
• eBNPs significantly reduced the colony-forming capacity of all tested glioma cell lines during BNCT compared to BPA.
• The efficacy of both eBNPs and BPA varied depending on the specific glioma cell line.

Conclusions:

• Synthesized eBNPs are a promising candidate for BNCT, demonstrating superior efficacy over BPA in reducing tumor cell survival.
• Further research focusing on tumor-targeting modifications of eBNPs is warranted for future in vivo studies.