Begin by adding 100 microliters of the prepared carbon dot solution into 200 microliters of chloroauric acid at room temperature for 10 seconds until a purple suspension is formed. Next, centrifuge the purple suspension at 4, 000 G for 10 minutes at room temperature. Gently remove the supernatant using a pipette if removing the gold carbon dot's composite nanoparticles colloids is difficult.
Resuspend the gold carbon dot's composite nanoparticles in 200 microliters of deionized water to wash away excess carbon dots. Centrifuge the suspension once again, remove the supernatant, and obtain the core shell nanoparticles by redispersing them in 100 microliters of deionized water. Store the mixture at four degrees Celsius.
