Table 1.

Carbon to oxygen ratio, nitrogen and phosphorous content of electrodes modified with four different concentrations of GO, after electrochemical reduction and after immobilization of ssDNA probe on the surface (values for DNA probe: C/O, 1.67; N(%), 10.02; P(%), 1.01).

Sample		GO	RGO	RGO + DNA probe
0.05 mg/mL	C/O	3.599	5.588	6.551
	N(%)	2.57	3.14	2.83
	P(%)	0	0	0.51
0.1 mg/mL	C/O	2.983	5.646	6.692
	N(%)	1.31	2.33	3.06
	P(%)	0	0	0.6
0.15 mg/mL	C/O	2.823	5.654	6.724
	N(%)	2.06	2.17	3.13
	P(%)	0	0	1.04
0.2 mg/mL	C/O	2.739	5.88	7.23
	N(%)	2.06	2.46	3.05
	P(%)	0	0	0.3