A simple, sensitive cupric oxide nanoparticles (CuO NPs) enhanced chemiluminescence (CL) method was developed for the measurement of β-lactam antibiotics, including amoxicillin and cefazolin sodium. The method was based on suppression of the CuO NPs-luminol-H2O2 CL reaction by β-lactam antibiotics. Experimental parameters that influenced the inhibitory effect of the antibiotic drugs on the CL system, such as NaOH (mol/L), luminol (µmol/L), H2O2 (mol/L) and CuO NPs (mg/L) concentrations, were optimized. Calibration graphs were linear and had dynamic ranges of 1.0 × 10(-6) to 8.0 × 10(-6) mol/L and 3.0 × 10(-5) to 5.0 × 10(-3) mol/L for amoxicillin and cefazolin sodium, respectively, with corresponding detection limits of 7.9 × 10(-7) mol/L and 1.8 × 10(-5) mol/L. The relative standard deviations of five replicate measurements of 5.0 × 10(-6) amoxicillin and 5 × 10(-4) cefazolin sodium were 5.43 and 5.01%, respectively. The synthesized CuO NPs were characterized by X-ray diffraction (XRD) and transmission electronmicroscopy (TEM). The developed approach was exploited successfully to measure antibiotics in pharmaceutical preparations.

A simple and sensitive chemiluminescence (CL) method has been developed for the determination of ampicillin sodium at submicromolar levels. The method is based on the inhibitory effect of ampicillin sodium on the cupric oxide nanoparticles (CuO NPs)-luminol-H2 O2 CL reaction. Experimental parameters affecting CL inhibition including concentrations of CuO NPs, luminol, H2 O2 and NaOH were optimized. Under optimum conditions, the calibration plot was linear in the analyte concentration range 4.0 × 10(-7) -4.0 × 10(-6) mol/L. The limit of detection was 2.6 × 10(-7) mol/L and the relative standard deviation (RSD) for six replicate determinations of 1 × 10(-6) mol/L ampicillin sodium was 4.71%. Also, X-ray diffraction (XRD) and transmission electron microscopy (TEM) analysis were employed to characterize the CuO NPs. The utility of the proposed method was demonstrated by determining ampicillin sodium in pharmaceutical preparation.