本實驗應用一套快速、靈敏的微管高效液相層析技術，偵測大白鼠腦部和血液中的非結合態橙皮素，此技術已發展應用於藥品的採樣。高效液相層析系統中，使用逆相碳18微管柱(100 × 1 mm I.D., 粒徑5 μm)，移動相為acetonitrile-methanol-20 mM monosodium phosphate (pH 5.3) (40:10:50, v/v/v)，流速0.05 mL/min，紫外光偵測波長設定在最大吸收值288 nm 。微透析探針分別插入雄性大白鼠的頸靜脈（即進入右心房）和腦部紋狀體。實驗方法是將橙皮素注入六隻大白鼠的股靜脈，每隻大白鼠之注射劑量為50 mg/kg，然後分別收集血液與腦部之微透析液並進行分析。根據所得之個體數據可計算藥物動力學參數，並求得橙皮素透析液濃度與時間之關係。

A rapid and sensitive microbore high-performance liquid chromatography (HPLC) coupled to microdialysis technique for simultaneous
determination of unbound hesperetin in rat blood and brain has been developed. The HPLC assay was carried out using a microbore
reversed-phase C-18 column (100 × 1 mm I.D., 5 μm particle size). The mobile phase used was acetonitrile-methanol-20 mM monosodium
phosphate (pH 5.3) (40:10:50, v/v/v) for hesperetin at a flow-rate of 0.05 mL/min. The assay was performed by monitoring the wavelength
of maximum UV absorbance at 288 nm. Microdialysis probes were inserted into the jugular vein/right atrium and brain striatum of
male Sprague-Dawley rats. Hesperetin (50 mg/kg, i.v., n=6) was administered via the femoral vein, and microdialysates were collected
from both sites and assayed by the validated microbore scale HPLC method. Pharmacokinetic parameters were calculated from the corrected
data for dialysate concentrations of hesperetin versus time.