Ms. Nelly Leshinsky - M.Sc. Candidate
05/07/2026
David Wang Auditorium, 3rd Floor, Dalia Maydan Bldg.
13:30
Sonodynamic therapy (SDT) is a localized treatment approach in which accumulated sonosensitizers in the tumor triggered by external low-intensity ultrasound (US) and leads to cancer cell apoptosis due to oxidative stress caused by localized cytotoxic reactive oxygen species (ROS). Hybrid nanomaterials offer a promising platform to enhance SDT by improving the delivery, targeting, and activation of sonosensitizing agents in pediatric solid tumors. Previous work in our lab developed hybrid amorphous titanium dioxide (TiO2)/polymer nanoparticles (NPs) of controlled size which showed their sonodynamic activity in vitro and in vivo. In this research, the surface of the NPs was modified with guanidino benzoic acid (GBA) to potentially improve the cellular uptake, through electrostatic and hydrogen-bonding interactions with central receptors in the tumor biology, and therefore the SDT efficacy. For this, a poly(ethylene oxide)-poly(propylene oxide) block copolymer was modified by the conjugation of GBA prior to the synthesis of the NPs and chemically characterized using ATR-FTIR and 1H NMR. GBA-modified NPs with a size of 98 ± 7 nm and a zeta-potential of -19 ± 1 mV, as measured by dynamic light scattering, were obtained. HR-SEM showed that the NPs are spherical. Then, the cellular uptake was evaluated on two neuroblastoma cell lines using imaging flow cytometry and confocal microscopy. Results showed that GBA-modified NPs increased the cellular uptake by 20%. This study contributes to the preliminary evaluation of GBA-modified hybrid nano-sonosensitizers and provides initial insights into their potential to improve cellular uptake within the broader context of SDT-based approaches for the therapy of pediatric solid tumors.