The popularity of nanotechnology-based sensing technologies has rapidly expanded within the past decade. Surface-enhanced Raman spectroscopy (SERS) is one such technique capable of chemically specific and highly sensitive measurements. The careful preparation of SERS-active nanoprobes is immensely vital for biological applications where nanoprobes are… (More)
Figure 1. (a) Schematic of prepared gold nanospheres with alternating layers of PAA (light blue shell), PAH (red shell), and methylene blue (blue stars). To prevent aggregation in highly ionic solutions, BSA (purple circles) was bound to the outer layer. (b) Transmission electron micrograph of gold nanospheres. Scale bar: 50 nm. (c) Representative ζ-potential for each surface coating in the synthesis. (d) Electronic absorption spectra of CTAB-stabilized gold nanospheres (dotted line) compared to polyelectrolyte-wrapped nanospheres (solid line).