Table 2.

In vitro cytotoxic activities of quercetin against mammalian cells.

Cells	Methods	Incubation time	CC50	References
Human Chang liver cell line	MTT assay	48 h	868.22 ± 3.81 μM	[56]
Human fetal lung fibroblast cell line MRC-5	Alamar Blue assay	72 h	>80 μM	[27]
Human hepatocellular carcinoma cell line HepG2	Alamar Blue assay	72 h	>80 μM	[27]
Human intestinal adenocarcinoma cell line HCT-8	MTT assay	48 h	>100 μM	[60]
Human keratinocyte cell line HaCaT	LDH assay	24 h	>10 μM for both Que and QAgNPs	[68]
Human macrophage cell line U937	Acid phosphatase assay	48 h	70 ± 10.7 μM	[33]
Human monocyte cell line U937	Acid phosphatase assay	48 h	24.9 ± 3.5 μM	[33]
Human promyelocytic leukemia cell line HL-60	Alamar Blue assay	72 h	51.3 ± 0.4 μM	[27]
Human red blood cells	Measurement of Hb release	30 min	A hemolysis percentage of <1 at 1000 μg/mL	[67]
Human red blood cells	Measurement of Hb release	3 h	A hemolysis percentage of <10 at 1000 μg/mL	[43]
Monkey kidney cell line BGM	MTT assay	24 h	≥1000 μg/mL	[55]
Madin-Darby canine kidney (MDCK) cell line	MTT assay	48 h	>100 μM	[60]
Rat myoblast cell line L6	Alamar Blue assay	72 h	37.1 μg/mL	[32]
Murine macrophage cell line J774.2	Trypan blue assay	72 h	125.44 μM	[25]
Murine macrophage cell line J774	MTT assay	144 h	>1000 μg/mL for both Que and QPNPs	[36]
Murine macrophage cell line RAW 264.7	Trypan blue assay	24 h	27.3 μM	[41]
Murine peritoneal macrophages	MTT assay	24 h	No loss of viability at 48 and 70 μM	[26]
Murine peritoneal macrophages	MTT assay	48 h	44.5 ± 1.7 μM (13.3 ± 0.5 μg/mL)	[19]
Murine peritoneal macrophages	Microscopic counting	48 h	1400 and 1600 μM for Que and QAunp, respectively	[34]
Murine peritoneal macrophages	Alamar Blue assay	72 h	80.2 μM	[20]
Hamster peritoneal macrophages	MTT assay	48 h	478 ± 89 μM	[28]

CC₅₀: the 50% cytotoxic concentration; Hb: hemoglobin; LDH: lactate dehydrogenase; QAgNPs: quercetin-conjugated silver nanoparticles; QAunp: quercetin-conjugated gold nanoparticles; QPNPs: quercetin-loaded poly-ε-caprolactone nanoparticles; Que: quercetin.