Electrochemical sensors based on carbon nanotubes - Electrochemical Sensors, Biosensors and Their Biomedical Applications - page 475

50

(a)

iv

40

30

20 iii

10

ii

i

0

10

0.2 0.4 0.6 0.8 1.0 1.2

E /V vs SCE

14

(b)

25

12

ii

20

15

10

10

iv

8

5

0

0.2 0.4 0.6 0.8 1.0 1.2

6

E/V vs SCE

iii

4

i

2

0

0.2 0.4 0.6 0.8 1.0 1.2

E /V vs SCE

FIGURE 15.12 Cyclic voltammograms (a) and differential pulse voltammograms (b) of 1 mg m 1 DNA
in a 0.1 M phosphate buffer (pH 7.4) at a bare GC electrode (i) and CNT-modifi ed GC electrodes using
CTAB (ii), Triton X-100 (iii), and SDS (iv) as dispersants. The inset in (b) shows a differential pulse voltam-
mogram of 1 µg ml 1 adenine in a 0.1 M phosphate buffer (pH 7.4) at the CNT/CTAB-modifi ed GC elec-
trode. Accumulation time: 5 min. The scan rate of cyclic voltammetry is 0.1 V s 1 . The pulse amplitude of
differential pulse voltammetry is 50 mV, and the pulse width is 50 ms (unpublished results).