| 摘要 |
The invention relates to substances for the production of anions which are suitable for charge transfer reactions in mass spectrometers. Diketones, particularly α-diketones and Ï -diketones with a mass 100 Dalton, are proposed as a newly found class of substances which can be used for the production of radical anions for electron transfer dissociations (ETD) with a high yield of fragment ions, and also for the production of non-radical anions for the charge reduction of multiply charged analyte ions by proton transfer reactions (PTR). Examples of suitable diketones include: open chain branched or unbranched alkane α-diketones such as 2,3-pentanedione, 3,4-hexanedione, 2,3-hexanedione, 3,4-heptanedione, 2,3-heptanedione, 2,3-octanedione, 2,2,5,5-tetramethylhexane-3,4-dione, or 2,2,7,7-tetramethyloctane-4,5-dione; cyclic α-diketones such as 3,5,5-trimethyl-1,2-cyclohexanedione; hex-3-ene-2,5-dione; or camphorquinone. These substances are largely nontoxic and their volatility means that they can be stored in unheated refillable containers outside of the vacuum system. |
