Additives
Residual activity (%)
1 mmol∙L−1
5 mmol∙L−1
Na+ (control)
100
100
K+
117 ± 1.9
531 ± 4.6
115 ± 1.6
492 ± 5.0
Mg2+
105 ± 1.6
206 ± 0.8
Ca2+
67 ± 2.0
63 ± 5.1
Fe3+
27 ± 2.5
12 ± 1.6
Mn2+
124 ± 2.2
89 ± 0.5
Cu2+
52 ± 3.9
39 ± 1.9
Co2+
43 ± 1.3
33 ± 4.8
Zn2+
20 ± 1.3
7 ± 3.6
Ni2+
1 ± 0.1
1 ± 3.5
Pb2+
50 ± 0.9
31 ± 0.8
Hg2+
0 ± 0
0 ± 0.0
β-mercaptoethanol
107 ± 2.3
250 ± 0.0
EDTA
108 ± 2.1
562 ± 5.0