Silica-coated gold nanoparticles were vortexed for 30 seconds and then sonicated using a bath sonicator for 10 minutes. Subsequently, a solution of Copoly Azide 4% at 1% w/v was prepared. SiGNPs were diluted to a final concentration of 1.4 OD by suspending 20 uL of SiGNPs in 480 uL the polymer solution; the sample was incubated for 1 hour at 25°C under stirring. At the end of the incubation, the sample was centrifuged for 5 minutes at 13,400 rpm, the supernatant was removed, and SiGNPs resuspended in 500 µL of MQ water.