A Chelating Resin of EDTA-Type Modified Cross-Linking Polystyrene to Preconcentrate Trace Metals for Seawater Detection

Table 3

Diluted standard seawater.

Metals	Standard seawater, µg/L	1/2, µg/L		1/4, µg/L		1/8, µg/L		1/10, µg/L
		A/D^1	PS^2	A/D	PS	A/D	PS	A/D	PS
Cu	5.0 ± 0.4	2.490	2.489	1.248	1.245	0.620	0.615	0.511	0.485
Zn	70 ± 3.0	35.01	34.31	17.48	17.43	8.762	8.729	7.053	6.901
Pb	10.0 ± 0.6	4.982	4.987	2.492	2.486	1.251	1.243	0.981	0.962
Cd	1.00 ± 0.06	0.495	0.491	0.251	0.248	0.120	0.116	0.097	0.091

¹A/D: APDC/DDTC treatment; ²PS: CAPS preconcentration.