Proteomics by mass spectrometry (MS) allows for the identification of amino acid/peptide sequences in complex mixtures. Peptide analysis and quantitation enables screening of protein biomarkers and targeted protein biomarker analysis for clinical applications. Whereas miniature mass spectrometers have primarily demonstrated point-of-care analyses with simple procedures aiming at drugs and lipids, it would be interesting to explore their potential in analyzing proteins and peptides. In this work, we adapted a miniature MS instrument for peptide analysis. A mass range as wide as 100-2000 m/z was achieved for obtaining peptide spectra using this instrument with dual linear ion traps. MS2 and MS3 can be performed to analyze a wide range of peptides. The parameters of pressure, electric potentials, and solution conditions were optimized to analyze peptides with molecular weights between 900 and 1800 Da. The amino acid sequences were identified using both beam-type and in-trap collision-induced dissociation, and the results were comparable to those obtained by a commercial quadrupole time-of-flight mass spectrometer. With product ion monitoring scan mode, peptide quantitation was performed with a limit of detection of 20 nM achieved for the Met peptide. The method developed has also been applied to the analysis of the trypsin-digested cell lysate of SKBR3 cells with a low expression level of the Met gene.

中文翻译：

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使用微型质谱法进行肽的靶向定量。

通过质谱（MS）进行蛋白质组学分析，可以鉴定复杂混合物中的氨基酸/肽序列。肽段分析和定量可以筛查蛋白质生物标志物，并针对临床应用进行靶向蛋白质生物标志物分析。微型质谱仪主要通过简单的方法针对药物和脂质进行了现场护理点分析，但探索其在分析蛋白质和多肽方面的潜力将非常有趣。在这项工作中，我们采用了微型MS仪器进行肽分析。使用带有双线性离子阱的仪器获得的质谱图可达到100-2000 m / z的质量范围。可以执行MS2和MS3来分析各种肽。压力，电势，优化了溶液条件，以分析分子量在900至1800 Da之间的肽。使用束型和阱内碰撞诱导的解离来鉴定氨基酸序列，其结果与通过商业四极杆飞行时间质谱仪获得的结果相当。在产物离子监测扫描模式下，进行肽定量时，对于Met肽，检测限为20 nM。所开发的方法也已用于分析胰蛋白酶消化的Met基因表达水平较低的SKBR3细胞的细胞裂解液。结果与通过商用四极杆飞行时间质谱仪获得的结果相当。在产物离子监测扫描模式下，进行肽定量时，对于Met肽，检测限为20 nM。所开发的方法也已用于分析胰蛋白酶消化的Met基因表达水平较低的SKBR3细胞的细胞裂解液。结果与通过商用四极杆飞行时间质谱仪获得的结果相当。在产物离子监测扫描模式下，进行肽定量时，对于Met肽，检测限为20 nM。所开发的方法也已用于分析胰蛋白酶消化的Met基因表达水平较低的SKBR3细胞的细胞裂解液。