Table 6. Comparison of Our Sensor to Some of Imidazole-Based Chemosensors Reported in the Literature for Sensing Cu²⁺, Fe²⁺, and Fe³⁺.

sensor	method	ions	media used	binding constant	LOD	binding ratio	mechanism involved	ref.
(E)7(diethylamino)3((2phenylimidazo[1,2-a]pyridinylimino)methyl)-2H-chromen-2-one	colorimetric and fluorometric	Cu2+	DMSO, water	4.859 × 103 M–1	4.6 × 10–8 M	1:1	ICT and CHEF	(56)
triazole-appended imidazopyridine sensor	fluorometric	Cu2+, CN–	CH3CN, water	3.12 × 10–8 M–1	18.17× 10–6 M	1:1	MLCT	(57)
furan-2-yl substituted imidazoazine-based sensor	colorimetric and fluorometric	Cu2+	CH3OH, water	∼104 M–1	∼10–7 M	1:1	paramagnetic quenching	(58)
2-(3-(tert-butylamino)imidazo[1,2-a]pyridin-2yl) phenol	colorimetric and fluorometric	Al3+, Fe3+,Cr3+	CH3CN	2.77 × 106 M–1	1.9 × 10–9 M	1:1	attainment of coplanarity and CHEF	(59)
3-(4-methoxyphenyl)- 1-phenylbenzo[4,5]imidazo[1,2-a]-pyridine	fluorometric	Fe3+, Hg2+	EtOH, water	1.09 × 105 M1	4.0 ppb	1:1	LMCT and CHEF	(60)
(E)-5-((4-(diethylamino)-2-hydroxybenzyldene)amino)-1H-imidazole-4-carboxamide	colorimetric	Fe3+, Fe2+	bis–tris buffer	5.0 × 1010 M–1 (Fe3+) and 1.0 × 1010 M–1 (Fe2+ )	0.73 μM (Fe3+) 1.11 μM (Fe2+)	2:1		(61)
3,4-dimethoxyphenyl)(4-(3,4-dimethoxyphenyl)-1H-imidazol-2-yl) methanone oxime	fluorometric	Fe3+	DMSO			1:1	ESIPT and LMCT	(62)
present sensors (SS1 and SS2)	colorimetric and fluorometric	Cu 2+, Fe2+, Fe3+	THF, water	∼104	∼10–6	1:1 (Cu2+), 2:1 (Fe2+, Fe3+)	ICT