An iterative block-shifting approach to retention time alignment that preserves the shape and area of gas chromatography-mass spectrometry peaks.
An iterative block-shifting approach to retention time alignment that preserves the shape and area of gas chromatography-mass spectrometry peaks.
复制标题
一种迭代的块移动方法，用于保留时间比对，可保留气相色谱 - 质谱峰的形状和面积。
DOI：
10.1186/1471-2105-9-s9-s15
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发表时间：
2008-08-12
影响因子：
3
通讯作者：
Thaden, John J.
中科院分区：
文献类型：
--
作者：
Chae, Minho;Reis, Robert J. Shmookler;Thaden, John J.
代谢组学、石油和生物柴油化学、生物标志物发现以及依赖于复杂化学混合物的高分辨率剖析的其他领域生成包含数百万个检测器强度读数的数据集，每个读数沿着时间的沿着维度被唯一地寻址（例如，化学品在色谱柱上的保留时间），光谱值（例如，源自化学品的离子的质荷比）和分析运行编号。它们还必须依赖于数据预处理技术。特别是，运行间的化学物质的保留时间的差异构成了一个重要的障碍，必须清除特征提取，数据减少，知识发现可以随之而来。据报道（根据我们的经验），用于校准保留的对齐方法可能会使匹配的化学品错位，错误地对齐不同的化学品，对输入参数的选择值过度敏感，并导致峰形和峰面积的失真。我们提出了一种迭代块移动的保留时间校准方法，检测色谱特征，并通过保留时间，光谱，以及它们对对齐本身质量的影响来鉴定它们。将质量色谱图与选择作为参比品的色谱图成对对齐。在使用45次运行GC-MS实验的测试中，嵌段移位将保留的绝对偏差降低了30倍以上。在比对方面，它优于COW和XCMS，并且在保留峰面积方面具有明显的上级优势。迭代块移动是一种有吸引力的方法来对齐GC-MS质量色谱图，也可推广到其他二维技术，如HPLC-MS。
Metabolomics, petroleum and biodiesel chemistry, biomarker discovery, and other fields which rely on high-resolution profiling of complex chemical mixtures generate datasets which contain millions of detector intensity readings, each uniquely addressed along dimensions of time (e.g., retention time of chemicals on a chromatographic column), a spectral value (e.g., mass-to-charge ratio of ions derived from chemicals), and the analytical run number. They also must rely on data preprocessing techniques. In particular, inter-run variance in the retention time of chemical species poses a significant hurdle that must be cleared before feature extraction, data reduction, and knowledge discovery can ensue. Alignment methods, for calibrating retention reportedly (and in our experience) can misalign matching chemicals, falsely align distinct ones, be unduly sensitive to chosen values of input parameters, and result in distortions of peak shape and area. We present an iterative block-shifting approach for retention-time calibration that detects chromatographic features and qualifies them by retention time, spectrum, and the effect of their inclusion on the quality of alignment itself. Mass chromatograms are aligned pairwise to one selected as a reference. In tests using a 45-run GC-MS experiment, block-shifting reduced the absolute deviation of retention by greater than 30-fold. It compared favourably to COW and XCMS with respect to alignment, and was markedly superior in preservation of peak area. Iterative block-shifting is an attractive method to align GC-MS mass chromatograms that is also generalizable to other two-dimensional techniques such as HPLC-MS.