Reduced graphene oxide-supported gold nanostars for improved SERS sensing and drug delivery.

Development of novel surface-enhanced Raman scattering (SERS) substrates and how they interface target analytes plays a pivotal role in determining the spectrum profile and SERS enhancement magnitude, as well as their applications. We present here the seed-mediated growth of reduced graphene oxide-gold nanostar (rGO-NS) nanocomposites and employ them as active SERS materials for anticancer drug (doxorubicin, DOX) loading and release. By this synthetic approach, both the morphology of rGO-NS nanohybrids and the corresponding optical properties can be precisely controlled, with no need of surfactant or polymer stabilizers. The developed rGO-NS nanohybrids show tunable optical properties by simply changing growth reaction parameters, improved stability as compared to bare Au nanostars, and sensitive SERS response toward aromatic organic molecules. Furthermore, SERS applications of rGO-NS to probe DOX loading and pH-dependent release are successfully demonstrated, showing promising potential for drug delivery and chemotherapy.