Self-Assembled Plasmonic Vesicles of SERS-Encoded Amphiphilic Gold Nanoparticles for Cancer Cell Targeting and Traceable Intracellular Drug Delivery

Abstract

We report the development of bioconjugated plasmonic vesicles assembled from SERS-encoded amphiphilic gold nanoparticles for cancer-targeted drug delivery. This new type of plasmonic assemblies with a hollow cavity can play multifunctional roles as delivery carriers for anticancer drugs and SERS-active plasmonic imaging probes to specifically label targeted cancer cells and monitor intracellular drug delivery. We have shown that the pH-responsive disassembly of the plasmonic vesicle, stimulated by the hydrophobic-to-hydrophilic transition of the hydrophobic brushes in acidic intracellular compartments, allows for triggered intracellular drug release. Because self-assembled plasmonic vesicles exhibit significantly different plasmonic properties and greatly enhanced SERS intensity in comparison with single gold nanoparticles due to strong interparticle plasmonic coupling, disassembly of the vesicles in endocytic compartments leads to dramatic changes in scattering properties and SERS signals, which can serve as independent feedback mechanisms to signal cargo release from the vesicles. The unique structural and optical properties of the plasmonic vesicle have made it a promising platform for targeted combination therapy and theranostic applications by taking advantage of recent advances in gold nanostructure based in vivo bioimaging and photothermal therapy and their loading capacity for both hydrophilic (nucleic acids and proteins) and hydrophobic (small molecules) therapeutic agents.

Vesicular gold assemblies based on host–guest inclusion and its controllable release of doxorubicin

“…In our case, the weight fraction of hydrophilic PEG in PEG and PNIPAM was 30%, and the ratio of the number of PEG to the number of nanoparticles was three, so we hypothesized that the amphiphilic HIC would lead to vesicles above the LCST of PNIPAM. Figure 1 shows the morphology of HIC at 37 • C. In the transmission electron microscopy (TEM) image ( figure 1(a)), one can see an obvious contrast between the interior and the shell of the particles, which was a characteristic image of hollow spheres as reported [16][17][18][19][20][21]. At a higher magnification, closely attached individual nanoparticles on the shell were visible, demonstrating that the vesicles were actually composed of individual AuNPs.…”

Probing molecular cell event dynamics at the single-cell level with targeted plasmonic gold nanoparticles: A review

“…Upon successful release, DOX's fluorescence will be restored allowing for real-time drug delivery dynamic measurements to be conducted. Several groups have reported successful variations of this DDS format [136][137][138]. Our group has utilized this DDS in conjunction with the strongly enhanced Raman scattering from the DOX molecule to monitor the dynamic release of DOX in live human oral squamous cell carcinoma cells [8].…”

Noble Metal Nanoparticle Platform

“…For example, SERS reporter-coated gold nanoparticles were assembled into a monolayer of nanoparticle shells with size of about 200 nm in diameter using a mixture of hydrophilic PEG and hydrophobic pH-sensitive copolymer grafted "to" or "from" the nanoparticle surface [34]. The interior of the shells could be loaded with anticancer drugs such as doxorubicin (DOX).…”