CL system, the molar concentration of copper(II) acetate was
selected exactly equal to the molar concentration of CuO nanosheets
which was achieved in the optimization process (Section
‘Optimization of the experimental conditions’).
Furthermore, by careful examination of Fig. 3, it is manifested
that the intensity of CL response of the luminol–H2O2–CuO nanosheets
system to 5 mg L1 cloxacillin sodium is higher than the
intensity of the CL responses of luminol–H2O2 and luminol–
H2O2–Cu2+ systems, implying the possible higher sensitivity of
the luminol–H2O2–CuO nanosheets system for determination of
lower concentrations of cloxacillin sodium. So, luminal–H2O2–
CuO nanosheets system was selected for optimization of the effect
of the key parameters in determination of cloxacillin sodium in
distilled water in the next section.