Cellular Detection of Glutathione Using Synthesized Stable Sea Urchin-Like Gold Nanoparticles

Gold nanoparticles (AuNPs) have been widely studied in a great mass of cellular biomarkers detection and diagnostics due to their unique combination of physical and optical properties. Sea urchin-like gold nanoparticles (SUL-AuNPs) are well characterized multi-thorn gold nanostructures which possess at least four gold nanothorns on spherical gold surface, mimicking the morphology of sea urchin. Compared to spherical AuNPs, SUL-AuNPs showed a wide variety of light absorption and scattering properties, and the Surface-enhanced Raman Scattering (SERS) properties of SUL-AuNPs were also widely studied dependent on their surface morphology. Herein, three different diameters of SUL-AuNPs based on spherical AuNPs seed-mediated growth method by altering the amount of AuNPs in reaction system had been synthesized. The UV-vis spectrum of synthesized SUL-AuNPs displayed a shift from 550 nm to 650 nm compared to spherical AuNPs. FRET method was applied for the detection of GSH in hepatocytes and cell extracts using rhodamine B (RB) functionalized SUL-AuNPs, among the synthesized three different diameters SUL-AuNPs, 100nm RB-SUL-AuNPs displayed highest sensitivity for GSH detection. What's more, all synthesized SUL-AuNPs turned out to be membrane-permeable, and displayed ignorable cytotoxicity, which make SUL-AuNPs promising cellular thiols detection probes. In particular, it should be noted that the application of RB functionalized SUL-AuNPs exemplify ongoing efforts in design and utility of multifunctional nanoplatforms of SUL-AuNPs.