Improving surface-enhanced Raman scattering performance of gold-modified magnetic nanoparticles by using nickel-phosphorus film on polydimethylsiloxane

This work demonstrated that a Ni-P film deposited on polydimethylsiloxane (PDMS) substrate could influence the magnetic aggregation of gold-modified magnetic nanoparticles (Fe3O4/AuNPs), improving their performance in surface-enhanced Raman scattering (SERS) detection. A simple and low-cost electroless deposition process was used to deposit the Ni-P film on PDMS (PDMS-Ni-P). By combining the PDMS-Ni-P substrate and a permanent NdFeB magnet, the Fe3O4/AuNPs were aggregated, and the SERS signal for crystal violet was three orders of magnitude higher than that obtained by aggregating the nanoparticles only using the magnet. Moreover, SERS signals for adenine and thiabendazole were also improved using the PDMS-Ni-P substrate, providing limits of detection of 1.65 and 0.24 mg L-1, respectively.