Oxcarbazepine (10,11-dihydro-10-oxo-5H-dibenzo- [b,f]azepine-5-carboxamide, OXCBZ, Fig. 1) is a new antiepileptic medicine, presented onto the market in the Nineties. OXCBZ is structurally related to carbamazepine, of which it is a keto-derivative. These medicines are highly lipophilic and neutral at most pH values, and are used mainly for the cure of partial seizures and generalised tonic–clonic seizures [1]. Fig. 1. Chemical structure of OXCBZ Recently, rare earth oxide nanoparticles have found many applications because of their attractive structural and optical properties with wonderful luminescence efficiency in the visible region. Luminescence performance of rare earth oxides is mainly stem from the partially-filled 4f electronic shell. Between rare earth oxides, cerium oxide nanoparticles (CeO2 NPs) are interesting compounds for many possible uses for example solid state electrolyte for electrochemical tools, catalyst for automobile exhauster, sun screen for UV absorbents, luminescent materials, gas sensors, polishing materials, and oxygen storage capacity [2]. In this work, we used CeO2 NPs for enhancing chemiluminescence (CL) reaction of luminol-O2. Moreover, it was found that OXCBZ decrease the intensity of CeO2 NPs- luminol-O2 CL reaction such that there was linear relationship between the CL intensity and concentration of OXCBZ. After optimization of CL reaction conditions, the log log calibration curve (log[CL peak intensity] vs. log[OXCBZ]) was constructed for a series of seven standard solutions in the range of 1.0 ×10-6 – 6.0 ×10-5 mol L-1. The relative standard deviation (RSD) of the CL method calculated by nine replicate measurements of 6.0 ×10-5 mol L-1 OXCBZ was 4.79%. The CL method was used for the measurement of concentration of OXCBZ in pharmaceutical preparations.
