| GNPs | gold nanoparticles |
| PVA | poly (vinyl alcohol) |
| PVP | poly (vinyl pyrrolidone) |
| TEM | transmission electron microscopy |
| SEM | scanning electron microscopy |
| FIB | focused ion beam |
| DLS | dynamic light scattering |
| FT-IR | Fourier-transform infrared spectroscopy |
| Ct | concentration of citrate ions |
| Au | concentration of gold precursor |