Table 1.

In vitro and in vivo toxicity studies of gold nanoparticles of different shapes with different surface groups.

Nanoparticles	Morphology	Surface group	Model system	Remarks	Ref.
gold	spheres	PEG	in vivo	acute toxicity to liver and spleen	[53]
gold	spheres	citrate	in vitro	dose-dependent cytotoxicity	[49]
gold	nanospheres, nanostars, and nanorods	chitosan	in vitro	toxicity trend: nanorods > nanostars > nanospheres	[54]
gold	nanorods	CTAB	in vitro	cytotoxic	[60]
gold	spheres	citrate	in vivo	size-dependent toxicity	[65]
gold	spheres, triangles, rods, trigonal bipyramids	CTAB	in vivo	genotoxic	[67]