Multifunctional Magnetic and Photoresponsive Nanoparticles Prepared by Polymer Self-Assembly

MARIANO H. FONTICELLI; MARÍA BELÉN RIVAS AIELLO; CAROLINA VERICAT; GABRIEL LAVORATO; DANIEL O. MÁRTIRE

Viña del Mar

Congreso; XIV ELAFOT; 2019

Cancer is one of the main causes of mortality around the world. One of the most sought objectives in Nanomedicine is to develop new nanomaterials that can improve the efficiency of cancer treatments while minimizing their undesired side effects. This work aims to demonstrate the synthesis of a multifunctional nanomaterial that combines magnetic nanoparticles and a photoresponsive agent in a single theranostic platform.We synthesized monodisperse hydrophobic iron oxide nanoparticles (MNP) with a diameter of 10.8±1.5 nm by the method of Sun et al.1. To prepare water-dispersible nanoparticles loaded with a photoresponsive agent, the MNPs were assembled with the amphiphilic polymer poly(maleic anhydride-alt-1-octadecene) (PMAO) and dispersed in a sodium borate buffer. The hydrophobic MNPs are encapsulated by the non-polar ends of the polymer, allowing the incorporation of phenalenone (PN) as a photoactive agent, as shown in the scheme below.By taking advantage of the magnetic properties of the nanoparticles, we employed magnetic decantation as a purification method2 and investigated the spectroscopic properties of the precipitated and supernatant portions of the colloidal dispersion. Steady-state fluorescence spectroscopy confirmed that the photosensitizer is effectively incorporated into the assembly and revealed a photoluminescence band at λ≈500 nm (λexc=360 nm), which is red-shifted compared to the emission obtained for the PN in the absence of MNP.This multifunctional nanoparticle system is a proof-of-concept demonstration of an integrated material that would allow simultaneous application of magnetic hyperthermia and photodynamic therapies. Our approach is also a promising way to deliver hydrophobic photosensitizers, as the solubilization and targeting of these molecules remains one of the biggest problems for the effective of these therapies. Finally, the use of a polymer that is sensitive to changes in temperature or pH conditions could favor the release of the photosensitizer during the combined treatment.