Annan R S, Kresbach G M, Giese R W, Vouros P
Department of Chemistry and Barnett Institute, Northeastern University, Boston, MA 02115.
J Chromatogr. 1989 Mar 31;465(2):285-96. doi: 10.1016/s0021-9673(01)92666-4.
Electrophoric derivatives of 5-methylcytosine and 5-hydroxymethyluracil nucleobases are determined using high-performance liquid chromatography-mass spectrometry coupled via a moving-belt interface. Standards as well as samples derived from DNA are analysed. As little as 9.9 pg (signal-to-noise ratio 5) and 180 fg (signal-to-noise ratio 10) of the respective nucleobases are detected in the electron-capture negative chemical ionization mode, and linear responses are observed over a moderate dynamic range. In a comparison study, liquid chromatography-electron-capture negative chemical ionization mass spectrometry is found to have a sensitivity comparable to gas chromatography-electron-capture negative chemical ionization mass spectrometry for 5-hydroxymethyluracil. A detection limit of 60 fg (signal-to-noise ratio 5) by gas chromatography-mass spectrometry is only three-fold better than the amount detected by liquid chromatography-mass spectrometry using the same mass spectrometer.
使用通过移动带接口耦合的高效液相色谱 - 质谱法测定5 - 甲基胞嘧啶和5 - 羟甲基尿嘧啶核碱基的电泳衍生物。分析了标准品以及源自DNA的样品。在电子捕获负化学电离模式下，分别检测到低至9.9 pg（信噪比5）和180 fg（信噪比10）的相应核碱基，并且在适度的动态范围内观察到线性响应。在一项比较研究中，发现液相色谱 - 电子捕获负化学电离质谱法对5 - 羟甲基尿嘧啶的灵敏度与气相色谱 - 电子捕获负化学电离质谱法相当。气相色谱 - 质谱法的检测限为60 fg（信噪比5），仅比使用相同质谱仪的液相色谱 - 质谱法检测到的量好三倍。
