Anisotropic Gold Nanoparticle Decorated Magnetopolymersome: An Advanced Nanocarrier for Targeted Photothermal Therapy and Dual-Mode Responsive T1 MRI Imaging.

Abstract

Herein, we report the advanced polymer vesicle [made up of triblock polymer: poly(ethylene oxide)-co-poly(Cys-AuNP@FA)-co-poly(3-methoxypropylacrylamide] having encapsulated magnetic nanoparticle capable of targeted methotrexate delivery (having folic acid as tagging agent), photothermal therapy [anisotropic gold nanoparticle (AuNPs)] and stimuli-responsive T1-imaging (as MRI contrast agent). The prepared polymersome, called as magnetopolymersome (MPS), after encapsulation of magnetic nanoparticle (Gd-doped) is not only high yield and simple in synthesis but also possess very high biocompatibility, more than 95% drug encapsulation efficiency and effective near-infrared (NIR) responsive photothermal therapy. The MPS is highly stable under normal physiological environments and other extreme end conditions (like presence of serum or Triton-X 100) and have excellent stimuli-responsive (temperature and NIR) T1-contrast effect in vitro conditions (60.57 mM-1 s-1). To explore the role of shape of AuNPs on the photothermal therapy and drug delivery behavior of prepared nanocarrier, herein, we have synthesized four different shapes of AuNPs, i.e., spherical, triangle, rod, and flower. It was found that nanoflower-conjugated MPS shows the most efficient NIR responsive behavior in comparison to their other colleagues, which broke the ancient myth that spherical nanoparticle are the best candidate for drug delivery process. These features make nanoflower or other anisotropic nanoparticle-based polymersome a very promising and efficient nanocarrier for drug loading, delivery, imaging, and photothermal therapy.