Identification of Molecular Fragments in Equilibrium with Polysiloxane Ultrasmall Nanoparticles

During recent decades, ultrasmall inorganic nanoparticles have attracted considerable interest due to their favorable biodistribution, pharmacokinetics and theranostic properties. In particular, AGuIX nanoparticles made of polysiloxane and gadolinium chelates were successfully translated to the clinics. In an aqueous medium, these nanoparticles are in dynamic equilibrium with polysiloxane fragments due to the hydrolysis of Si-O-Si bonds. Thanks to high-performance liquid chromatography coupled with electrospray ionization mass spectrometry, all these fragments were separated and identified.

Automated summary

Ultrasmall inorganic nanoparticles have gained significant attention in recent years for their beneficial biodistribution, pharmacokinetics, and theranostic properties. AGuIX nanoparticles made of polysiloxane and gadolinium chelates have been successfully translated for clinical use. In aqueous mediums, these nanoparticles are in dynamic equilibrium with polysiloxane fragments due to the hydrolysis of Si-O-Si bonds. High-performance liquid chromatography coupled with electrospray ionization mass spectrometry has enabled the separation and identification of these fragments.