Sensitive determination of ultra-trace nitric oxide in blood using derivatization-polymer monolith microextraction...

Nitric oxide (NO) plays a very important role in human blood system. In this work, a novel approach has been developed for the quantitation of ultra-trace NO derivatized with 1,3,5,7-tetramethyl-8-(3',4'-diaminophenyl)-difluoroboradiaza-s-indacene (DAMBO) using a polymer monolith microextraction (PMME) with a poly(methacrylic acid-ethylene glycol dimethacrylate) (MAA-EGDMA) monolith in conjunction with high-performance liquid chromatography (HPLC). Both derivatization and PMME conditions have been optimized in detail. The detection limit of derivatized NO was 2x10(-12) mol L(-1) (signal to noise=3) and linear range was 9x10(-11)-4.5x10(-8) mol L(-1). The proposed DAMBO-based derivatization-PMME-HPLC-fluorescence detection method has been successfully applied for the determination of NO in 10 microL blood samples of healthy persons and patients suffering from ischemic cardio-cerebrovascular diseases with recoveries varying from 87.40 to 91.60%.