PMMA/SWCNTs nanocomposites for prostate brachytherapy MRI contrast agent markers

Interstitial brachytherapy became a standard treatment for prostate cancer in the last decade with outstanding long-term results. Magnetic Resonance Imaging (MRI) is the imaging modality of choice for the prostate, however, for prostate brachytherapy (PB) it is currently not utilized to its full potential because the radioactive titanium seeds generate MRI artifacts and appears as black holes (negative contrast) leading to unreliable localization within the prostate and periprostatic tissue by using MRI. To overcome this disadvantage, we developed a novel medical device referred to as Encapsulated Contrast Agent Markers (ECAMs), contained Co-based or Gd-based T₁ contrast agents that allows visualization of the precise location of radioactive titanium seeds by using MRI. We report here on fabrication of reinforce poly(methy 1 methacrylate) (PMMA) with single-walled carbon nanotubes (SWCNTs) nanocomposites that can be potentially used as capsulation materials for MRI prostate brachytherapy markers and study of their MRI response. In vitro testing of fabricated markers using clinical MRI sequencing protocols have demonstrated positive T₁ signal enhancement. This study revealed that fabricated PMMA/SWCNTs composites show potential as capsule materials for PB MRI markers.