Table 2.

Method Linearity.

Analyte	Metal	Linearity Range (nM)	r2	LOD (nM)	LOQ (nM)
Catechol	Fe(III)	9.0–450	0.9994	3.0	9.0
	Fe(II)	9.0–450	0.9993	3.0	9.0
	Cu(I)	3.0–450	0.9992	1.0	3.0
2,3-DHBA	Fe(III)	6.5–325	0.9998	2.0	6.5
	Fe(II)	6.5–325	0.9991	2.0	6.5
	Cu(I)	6.5–325	0.9995	2.0	6.5
2,5-DHBA	Fe(III)	6.5–325	0.9996	2.0	6.5
	Fe(II)	6.5–325	0.9997	2.0	6.5
	Cu(I)	2.0–325	0.9994	0.7	2.0