Department of Chemistry and the Ralph N. Adams Institute for Bioanalytical Chemistry, University of Kansas, 1251 Wescoe Hall Drive, Lawrence, KS 66045, USA.
Rapid Commun Mass Spectrom. 2010 Jan;24(1):6-10. doi: 10.1002/rcm.4352.
The recent worldwide shortage of acetonitrile has prompted interest in alternative solvents for liquid chromatography/mass spectrometry (LC/MS). In this work, acetone was substituted for acetonitrile in the separation of a peptide mixture by reversed-phase high-performance liquid chromatography (RP-HPLC) and in the positive electrospray ionization mass spectrometry (ESI-MS) of individual peptides. On both C12 and C18 stationary phases, the substitution of acetone for acetonitrile as the organic component of the mobile phase did not alter the gradient elution order of a five-peptide retention standard, but did increase peak width, shorten retention times, and increase peak tailing. Positive ESI mass spectra were obtained for angiotensin I, bradykinin, [Leu(5)]-enkephalin, and somatostatin 14 dissolved in both acetonitrile/water/formic acid (25%/75%/0.1%) and acetone/water/formic acid (25%/75%/0.1%). Under optimized ESI-MS conditions, the mass spectral response of [Leu(5)]-enkephalin was increased two-fold when the solvent contained acetone. The substitution of acetone for acetonitrile resulted in only slight changes in the responses of the remaining peptides. A higher capillary voltage was required for optimum response when acetone was used. Compared with acetonitrile/water/formic acid (50/50/0.1%), more interfering species below m/z = 140 were found in the ESI-MS spectra of acetone/water/formic acid (50/50/0.1%).
最近全球范围内乙腈短缺，促使人们对液相色谱/质谱（LC/MS）的替代溶剂产生了兴趣。在这项工作中，通过反相高效液相色谱（RP-HPLC）和单个肽的正电喷雾电离质谱（ESI-MS），将丙酮替代乙腈作为有机相成分用于肽混合物的分离。在 C12 和 C18 固定相上，用丙酮替代乙腈作为流动相的有机成分，不会改变五肽保留标准品的梯度洗脱顺序，但会增加峰宽、缩短保留时间并增加峰拖尾。在乙腈/水/甲酸（25%/75%/0.1%）和丙酮/水/甲酸（25%/75%/0.1%）中溶解的血管紧张素 I、缓激肽、[Leu(5)]-脑啡肽和生长抑素 14 都可以得到正 ESI 质谱。在优化的 ESI-MS 条件下，当溶剂中含有丙酮时，[Leu(5)]-脑啡肽的质谱响应增加了两倍。用丙酮替代乙腈只会导致其余肽的响应略有变化。当使用丙酮时，需要更高的毛细管电压才能获得最佳响应。与乙腈/水/甲酸（50/50/0.1%）相比，在丙酮/水/甲酸（50/50/0.1%）的 ESI-MS 谱中发现了更多低于 m/z = 140 的干扰物质。
