Cheng Guan-Wen, Wu Hsin-Lung, Huang Yeou-Lih
Graduate Institute of Pharmaceutical Sciences, Kaohsiung Medical University, Kaohsiung 807, Taiwan.
Talanta. 2009 Sep 15;79(4):1071-5. doi: 10.1016/j.talanta.2009.01.044. Epub 2009 Feb 4.
We have developed a system that couples an on-line microdialysis (MD) system with flow injection high-performance liquid chromatography (HPLC)-fluorescence detection for simultaneous measurement of the concentrations of malondialdehyde (MDA) and ofloxacin (OFL) in whole blood samples. The sample matrix was first cleaned with an MD system using an MD probe. A continuously flowing dialysate stream was derivatized on-line and auto-injected into a separation column. MDA and OFL were separated through a reverse-phase C18 column (250 mm x 4.6 mm) at a flow rate of 0.8 mL min(-1) and then detected using a fluorescence detector (excitation: 532 nm; emission: 553 nm); the system's components were connected on-line using a valve control. Validation experiments demonstrated good linearity, precision, accuracy, and recovery. The precisions for the determinations of MDA and OFL, measured in terms of relative standard deviations, were 6.5% and 4.6%, respectively, for intra-day assays and 7.5% and 8.7%, respectively, for inter-day assays. The average recoveries of MDA and OFL spiked in plasma were each close to 100%. The use of this on-line MD-HPLC system permitted continuous monitoring of MDA and OFL in OFL-treated whole blood subjected to UV-A irradiation. Based on our results, the UV-A irradiation markedly increased the level of MDA in the OFL-treated whole blood.
我们开发了一种系统，该系统将在线微透析（MD）系统与流动注射高效液相色谱（HPLC）-荧光检测相结合，用于同时测量全血样品中丙二醛（MDA）和氧氟沙星（OFL）的浓度。首先使用MD探针通过MD系统对样品基质进行净化。连续流动的透析液流在线衍生化，然后自动进样到分离柱中。MDA和OFL通过反相C18柱（250 mm×4.6 mm）以0.8 mL min⁻¹的流速分离，然后使用荧光检测器进行检测（激发波长：532 nm；发射波长：553 nm）；系统组件通过阀控在线连接。验证实验表明该系统具有良好的线性、精密度、准确度和回收率。以相对标准偏差衡量，日内测定MDA和OFL的精密度分别为6.5%和4.6%，日间测定分别为7.5%和8.7%。血浆中添加的MDA和OFL的平均回收率均接近100%。使用这种在线MD-HPLC系统可以对经UV-A照射的OFL处理全血中的MDA和OFL进行连续监测。基于我们的结果，UV-A照射显著提高了OFL处理全血中MDA的水平。
