摘要
采用电喷雾质谱法研究了偶氮胂Ⅲ离子化过程。结果发现,偶氮胂Ⅲ易于在电喷雾电离过程中通过去质子化作用形成带有单电荷或双电荷负离子。考察了酸度和醋酸根等离子对偶氮胂Ⅲ电喷雾电离的影响。结果表明,偶氮胂Ⅲ在弱酸性条件下有利于形成负离子。提出了偶氮胂Ⅲ在电喷雾电离源中通过去质子化作用形成负离子的可能机理,并用串联质谱法研究了所形成不同价态离子的裂解规律。结果表明,电喷雾串联质谱法能方便快捷地研究偶氮胂Ⅲ的电离行为和所形成不同价态离子的性质,其检测限达0.74×10-15g。
Electron spray ionization mass spectrometry （ESI-MS） was employed for direct investigation of arsenazo Ⅲ aqueous solutions. Experimentally, it was found that arsenazo Ⅲ formed singly （m/z 775 ） or doubly charged ions（ m/z 387） by deprotonation in the ESI process. Under the experimental conditions, the signal of m/z 387 was 20 times higher than that of m/z 775. The formation of the negative ions of arsenazo Ⅲ was favored in weakly acidic solution. The characteristic fragmentation patterns of the anions（ i. e. , m/z 775, m/z 387） of arsenazo Ⅲ were obtained by multiple stage tandem mass spectrometry with a collision energy of 15% -25%, providing evidence for identifying arsenazo Ⅲ in a complex mixture. The data showed that a low limit detection of 0. 74 × 10^-15 g was obtained with tandem mass spectrometry for the doubly charged anions （m/z 387 ）, showing that electrospray ionization tandem mass spectrometry is a useful tool for the study and detection of arsenazo Ⅲ.
出处
《应用化学》
CAS
CSCD
北大核心
2008年第5期510-513,共4页
Chinese Journal of Applied Chemistry
基金
国家自然科学基金(20505003)
国家科技部公益基金(2005DIB6J232)资助项目
关键词
偶氮胂Ⅲ
电喷雾
串联质谱
arsenazo Ⅲ, EsI, tandem mass spectrometry
作者简介
通讯联系人：陈焕文，男，博士，教授；E-mail：chw8868@gmail．com；研究方向：分析化学
