Anisotropic Bimetallic Core-Satellite-Poly(aniline) Nanohybrids for Detection of Autoantibodies

Bimetallic core-satellite nanoparticles are widely exploited in surface-enhanced Raman scattering (SERS)-based applications due to their enhanced optical properties compared to single-component metallic nanoparticles (MNPs). In addition, anisotropic hybrid nanostructures containing both MNPs and polymeric compartments constitute a new class of functional nanomaterials for photonic applications because they show different functionalities and physicochemical characteristics at two distinct compartments. Herein, synthesis of two kinds of anisotropic bimetallic core-satellite-poly(aniline) nanohybrids (ABCPNs) using small or polymeric ligand-coated gold nanospheres or gold nanorods as seeds is reported. The ABCPNs exhibit enhanced optical properties due to a local electromagnetic field generated in the narrow interparticle gap between core and satellite nanoparticles. Furthermore, a SERS-based quantitative analysis of autoantibodies against cyclic citrullinated peptide using the ABCPNs as SERS nanoprobes for a diagnosis of early rheumatoid arthritis is demonstrated, suggesting that these multifunctional nanostructures will be potential for advanced SERS-based biosensors.