Flight Robert M, Mitchell Joshua M, Moseley Hunter N B
Markey Cancer Center, University of Kentucky, Lexington, KY 40536, USA.
Department of Molecular & Cellular Biochemistry, University of Kentucky, Lexington, KY 40536, USA.
Metabolites. 2022 Jun 2;12(6):515. doi: 10.3390/metabo12060515.
We present a novel, scan-centric method for characterizing peaks from direct injection multi-scan Fourier transform mass spectra of complex samples that utilizes frequency values derived directly from the spacing of raw / points in spectral scans. Our peak characterization method utilizes intensity-independent noise removal and normalization of scan-level data to provide a much better fit of relative intensity to natural abundance probabilities for low abundance isotopologues that are not present in all of the acquired scans. Moreover, our method calculates both peak- and scan-specific statistics incorporated within a series of quality control steps that are designed to robustly derive peak centers, intensities, and intensity ratios with their scan-level variances. These cross-scan characterized peaks are suitable for use in our previously published peak assignment methodology, Small Molecule Isotope Resolved Formula Enumeration (SMIRFE).
我们提出了一种新颖的、以扫描为中心的方法，用于表征复杂样品直接进样多扫描傅里叶变换质谱中的峰，该方法利用直接从光谱扫描中的原始点间距导出的频率值。我们的峰表征方法利用与强度无关的噪声去除和扫描级数据的归一化，以便为并非在所有采集扫描中都存在的低丰度同位素异构体提供相对强度与自然丰度概率更好的拟合。此外，我们的方法在一系列质量控制步骤中计算峰和扫描特定的统计数据，这些步骤旨在稳健地得出峰中心、强度以及强度比及其扫描级方差。这些跨扫描表征的峰适用于我们之前发表的峰归属方法——小分子同位素解析分子式枚举（SMIRFE）。
