Self-assemblies of plasmonic gold/layered double hydroxides with highly efficient antiviral effect against the hepatitis B virus

Engineering complex nanocomposites that specifically target the hepatitis B virus (HBV) and overcome the limitations of current therapies such as limited efficacy and serious side effects is very challenging. Here, for the first time, the antiviral effect of engineered plasmonic gold and layered double hydroxide self-assemblies (AuNPs/LDHs) is demonstrated, using HBV as a model virus and hepatoma-derived HepG2.2.215 cells for viral replication, assembly, and secretion of infectious virions and subviral particles. AuNPs/LDHs were obtained by a simple, cost-effective procedure in which small AuNPs (similar to 3.5 nm) were directly obtained and organized on the surface of larger LDH nanoparticles (similar to 150 nm) by exploiting the capability of MgLDH, ZnLDH, and MgFeLDH to manifest their "structural memory" in the aqueous solution of Au(O2CCH3)(3). The self-assembly approach of AuNPs and LDHs was assessed by transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), powder X-ray diffraction (PXRD), and UV-Vis analysis (UV-Vis). All AuNPs/LDHs tested reduced the amount of viral and subviral particles released from treated cells by up to 80% and exhibited good cytocompatibility. AuNPs/MgFeLDH showed the highest antiviral HBV response with more than 90% inhibition of HBV secretion for the whole concentration range. Preliminary studies on the mechanism of HBV inhibition reveals that in the presence of AuNPs/LDHs, HBV particles are sequestered within the treated cells. The antiviral and low cytotoxic plasmonic properties of these Au/LDH nanocomposites indicate that they hold significant potential to be tailored as novel efficient therapeutics for the treatment of hepatitis B.