The effects of CuO nanosheets on the luminol–H2O2 CL system
were investigated. Fig. 3 shows the kinetic curves of the luminol–
H2O2 CL system. As shown in Fig. 3, the CL signals reach a maximum
within 10 s, which indicate the CL reaction is rapid. Also, it
can be seen that the CL intensity of luminol–H2O2 is relatively
weak in alkaline solution (Fig. 3, curve a). However, with the addition
of 12 mg L1 (1.5 104 mol L1) of CuO nanosheets, the CL
signal intensity is sharply enhanced up to about 10 folds (Fig. 3,
curve e). In order to explore the enhancing effect of CuO nanosheets,
blank experiments were performed using copper(II) acetate
and glacial acetic acid aqueous solutions in the concentration
which was used above for CuO nanosheets in luminol–H2O2 CL system.
No enhancing effect was observed in the presence of
1.5 104 mol L1 glacial acetic acid. But, the CL signal intensity
in the presence of 1.5 104 mol L1 copper(II) acetate was amplified
to about 4.47 times (curve c).
Moreover, as shown in Fig. 3, when 5 mg L1 cloxacillin sodium
is added into each of the luminol–H2O2, luminol–H2O2–Cu2+ and
luminol–H2O2–CuO nanosheets CL systems, the CL signal intensity
is increased, revealing that these CL systems can be applied to
the determination of cloxacillin sodium. However, in order to