Development of polymer-encapsulated metal nanoparticles as surface-enhanced Raman scattering probes

A study was conducted to demonstrate the development of polymer-encapsulated metal nanoparticles (NP), as surface-enhanced Raman scattering (SERS) nanoprobes. The study demonstrated the encapsulation of analyte-tagged metal NPs by an amphiphilic polystyrene-block-poly(acrylic acid) diblock copolymer through self-assembly. It was demonstrated that the thermodynamically controlled process is suitable in polymer shells, having uniform thickness. It was found that these polymers were prepared, without the need for significant control, requiring a one-spot synthesis that involved simple heating and cooling. It was observed that the synthesis process is scalable and highly reproducible, giving large quantities of nanoprobes that can be isolated by direct centrifugation and resuspension in water. It was also observed that the polymer shells protect the encapsulated nanoprobes against salt-induced aggregation and oxidation by oxone (HSO₅^-.