Simultaneous Determination of Unbound Cefoperazone in Rat Blood and Brain Using Microdialysis

Abstract

Abstract A sensitive microbore HPLC method was developed for the simultaneous determination of unbound cefoperazone in rat blood and brain using microdialysis. Two microdialysis probes were inserted into the jugular vein/right atrium and brain striatum of Sprague—Dawley rats. Cefoperazone (50 mg kg−1, i.v.) was then administered via the femoral vein. Blood and brain dialysates were collected and eluted with a mobile phase containing methanol-100 mM monosodium phosphoric acid (30:70, v/v, pH 5.5). The wavelength of the UV detector was set at 254 nm. The detection limit of cefoperazone was 20 ng mL−1. Isocratic separation of cefoperazone was achieved within 10 min. The intra- and inter-assay accuracy and precision of the analyses were ≤ 10% in the range of 0.05–10 μg mL−1. The ratio of the area under the concentration curve of cefoperazone in rat brain and blood was estimated to be about 7.8%. It is concluded that cefoperazone is capable of penetrating the blood—brain barrier.