Table 1.

Summary of the colorimetric μPADs for glucose detection in representative references. TMB: 3,3′,5,5′-tetramethylbenzidine.

Reference	Indicator	Barrier	Limits of Detection
Garcia et al. (2014) [62]	KI	Paraffin	0.1 mM
Cai et al. (2014) [59]	KI	TMOS	Not mentioned
Li et al. (2016) [86]	KI	Wax	Not mentioned
Mohammadi et al. (2015) [88]	KI	PDMS	5 mM
Oyola-Reynoso et al. (2015) [92]	KI	Trichloro silane	5.5 mM
Chen et al. (2012) [4]	4-AAP/TOPS	Paper pieces	0.21 mM
Zhu et al. (2014) [94]	4-AAP/TBHBA	Paper pieces	0.3 mM
Zhou et al. (2014) [61]	APTMS/GA	Paper pieces	0.25 mM
Soni et al. (2015) [97]	Methyl red	Paper pieces	1.23 mM
Cate et al. (2013) [35]	DAB	Paper pieces	1.11 mM
Figueredo et al. (2016) [99]	TMB	Paper pieces	0.043, 0.062 and 0.018 mM (with different nanomaterials)
Palazzo et al. (2012) [98]	AuNPs	Paper pieces	0.1 mM
Deng et al. (2014) [105]	ABTS	Paper pieces	9 nM
Im et al. (2016) [109]	4-AAP/MAOS	Wax	0.3 mM
Gabriel et al. (2016) [96]	4-AAP/DHBS	Paraffin	0.023 mM