Table 3.

Comparisons of existing sialidase assay methods

	TBA assay	TLC	Radiochemical method	1 H-NMR	HPLC	Fluorescence assay	Spectophotometric assay
Substrates	Sialosides	Sialosides	Sialosides	Sialosides	Sialosides	4MU-Neu5Ac	pNP-Neu5Ac
Reagents	Arsenite, TBA	Resorcinol or diphenylamine	Radiolabelled gangliosides	Deuterated buffer	Malonitrile	Normal buffer	Normal buffer
Instruments	Spectrometer	TLC plate	HPTLC and radiochromatoscanner	NMR facility	HPLC and fluorimeter	Fluorimeter	Spectrophotometer
Time to run	hours	hours	hours	hours	hours	10 min	10 min
Safety issue	5TC toxic	Hazardous in case of skin contact	Radioactive substrate	Strong magnet	None	None	None
Automation	No	No	No	No	Yes	Yes	Yes
Cost per run	Cheap	Cheap	Expensive	Very Expensive	Expensive	Expensive and substrate unstable	Cheap
Substrate specificity	Yes	Yes	Yes	Yes	Yes	No	No
Enzyme kinetics	Inaccurate; Time consuming	Not applicable	Costly; Time consuming	Costly; Time consuming	Costly; Time consuming	Yes	Yes
Reference(s)	[8]	[9]	[10]	[3,11]	[20]	[7,12,16]	[12]