Table 1. Detection of HER2 in Human Serum Samples Using the Electrochemical Immunoassay and a Commercial HER2 ELISA Kit.

	method; concn (mean ± SD, ng mL–1, n = 3)
sample no.	electrochemical immunoassay	RSD (%)	HER2 ELISA kit	RSD (%)	texp
1	0.32 ± 0.02	6.25	0.34 ± 0.03	8.82	0.96
2	4.59 ± 0.21	4.58	4.33 ± 0.18	4.16	1.62
3	9.86 ± 0.30	3.04	9.67 ± 0.25	2.59	0.84
4	1.36 ± 0.08	5.88	1.29 ± 0.06	4.65	1.21
5	8.02 ± 0.20	2.49	7.88 ± 0.17	2.16	0.92