Table 3.

OP^DTT and OP^AA responses (depletion rate nmol min⁻¹) of standard solutions of redox-active species. OP assays were performed in pure water, phosphate buffer and Gamble’s solution media on the laboratory solutions and after extraction with different solvents on spiked blank quartz filters. For each species, measurements were repeated at least 3 times (mean and standard deviation, n ≥ 3)

OPDTT (nmol min-1)				OPAA (nmol min-1)
Standard solution	Pure water	Phosphate buffer	Gamble’s solution	Standard solution	Pure water	Phosphate buffer	Gamble’s solution
Cu2+ (1 μM)	3.49±0.12	3.33±0.19	2.49±0.14*	Cu2+ (0.17 μM)	5.42±0.24	5.31±0.31	4.49±0.27
Fe2+ (1 μM)	0.52±0.03	0.48±0.03	0.34±0.03	Fe2+ (1 μM)	1.12±0.06	1.07±0.06	0.97±0.06
1,2-NPQ (0.5 μM)	1.92±0.09	1.82±0.11	1.13±0.07*	1,2-NPQ (0.5 μM)	4.95±0.25	4.81±0.28	3.91±0.21
9,10-PNQ (0.17 μM)	1.42±0.06	1.38±0.08	1.26±0.07	9,10-PNQ (1 μM)	0.91±0.05	0.91±0.06	0.60±0.03*
OPDTT (nmol min-1)
Spiked blank filters	Pure water	Phosphate buffer	Gamble’s solution	Methanol
Cu2+ (0.5 μM)	1.93±0.10	1.84±0.11	1.21±0.09*	0.23±0.02*
Fe2+ (1 μM)	0.58±0.04	0.55±0.04	0.38±0.03	ND
1,2-NPQ (0.5 μM)	1.20±0.07	1.17±0.08	0.75±0.05*	1.41±0.11*
9,10-PNQ (0.17μM)	1.05±0.08	1.06±0.09	0.95±0.04	1.65±0.12*
OPAA (nmol min-1)
Spiked blank filters	Pure water	Phosphate buffer	Gamble’s solution	Methanol
Cu2+ (0.5 μM)	4.02±0.25	4.76±0.28	4.35±0.26	ND
Fe2+ (1 μM)	1.25±0.08	1.29±0.09	1.12±0.06	ND
1,2-NPQ (0.5 μM)	3.52±0.19	3.62±0.23	2.95±0.15*	4.87±0.38*
9,10-PNQ (0.17μM)	0.85±0.03	0.78±0.05*	0.53±0.01	1.38±0.08*

ND OP response lower than that of the blank quartz filter