Table 1.

Mechanisms of interference between nonbiodegradable NPs and in vitro assays

Mechanism	Assay(s)	Particle(s)	Reference(s)
Absorbance	Hemolysis	Au, C60	128–130
	LAL	Au, C60	131
	MTT	Au, CB, C60, Qdots, Ag, AgO, iron oxide, SWCNT	90, 92, 93, 129, 132–136
	WST-1	Iron oxide	137
	MTS	Al, Qdots	51, 97, 138
	LDH	Au, SiO2, iron oxide, CeO2	51, 98, 135, 139
Light scattering	MTT, ATP	Carbon nanodiamonds	140
Dye absorption	MTT	SWCNT, CB, Al, iron oxide	95, 141–144
	NR	CB, SWCNT, C60, Si, TiO2	90, 134, 141, 145–148
	AB, AK	SWCNT	146
	CB, WST-1	SWCNT	145
Enzyme inactivation/inhibition	LDH	Cu, Ag	149, 150
	LDH	ZnO	135
	LDH	Si, Au, Qdots	96
	LDH	Au	151
	AK	PS	105
Enzyme adsorption	LDH	Cu, Qdots, TiO2	93, 95, 133, 149, 152, 153
Reduction/enzymatic activity	MTT	Si, SWCNT, C60, TiO2	91, 95, 129, 145, 148, 152, 154, 155
	AB	Si	148
	AK	SWCNT	146
Prevention of reduction	MTT	Zn	93
Oxidation	H2DCF	CB	135
	Hemoglobin	Iron oxide	128
Protein binding	Cytokines	CB, SWCNT, iron oxide, Cu, SiO2, Al2O3, CeO2, NiO2, TiO2	93, 135, 141, 146, 156–159
Increase enzymatic activity	LAL	Iron oxide	131
	Hemoglobin	PS, SWCNT	129, 146
Physical interaction	TB, calcein AM, live/dead	SWCNT, C60, CB, Qdots	90
	COMET	Ge	160
Quenching of fluorescence	H2DCF	CB, SiO2, SiO2-iron	161, 162
	LDH	CB, SWCNT, C60, Qdots	90
	Calcein AM/EthD-1	CB, SWCNT	90
Increase of fluorescence	H2DCF	Au, iron oxide, TiO2, C60, SiO2, CB, SWCNT	91–95
	PI	Qdots, PS	95
	Calcein AM/EthD-1	CB, iron oxide	91
	AB	CB, SWCNT, TiO2, Qdots	90, 97, 145
	Resazurin	CoO	51
	COMET	TiO2, CuO	163
Increase of luminescence	Phagocytosis	Qdots	130
	ATP	SiO2	139
Quenching of luminescence	Phagocytosis	Au	129, 131
Aggregation	Platelet aggregation	Au, C60	129

Abbreviations: NPs, nanoparticles; Au, gold; C₆₀, C₆₀ fullerenes; LAL, limulus amebocyte lysate; CB, carbon black; Qdots, CdSe quantum dots; Ag, silver; SWCNT, single-walled carbon nanotube; WST-1, water soluble tetrazolium salt; MTS, 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium); Al, aluminum; LDH, lactate dehydrogenase; SiO₂, silica; CeO₂, cerium oxide; ATP, adenosine triphosphate; NR, neutral red; TiO₂, titanium dioxide; AB, alamarBlue; AK, adenylate kinase; Cu, copper; ZnO, zinc oxide; PS, polystyrene; Zn, zinc; H₂DCF, dihydrodichlorofluorescein; Al₂O₂, aluminum oxide; NiO₂, nickel oxide; TB, trypan blue; AM, acetoxymethylester; Ge, germanium; EthD-1, ethidium homodimer 1; PI, propidium iodide; CoO, cobalt oxide; CuO, copper (II) oxide.