GC-IMS dataset of pooled human urine for chromatographic alignment studies

This dataset contains gas chromatography–ion mobility spectrometry (GC-IMS) measurements acquired from pooled human urine samples. The data were generated to support methodological research on chromatographic alignment and signal processing approaches applied to GC-IMS data. Urine samples were collected from eleven healthy volunteers (five female and six male). First-morning fasting urine was obtained and pooled under controlled conditions. The pooled sample was aliquoted into multiple vials and stored frozen until analysis. Prior to measurement, each vial was prepared with sodium chloride to enhance volatilization, an internal standard solution (2-decanone), and hydrochloric acid. The prepared samples were then analysed using headspace GC-IMS. The study protocol was approved by the Ethics Committee of Hospital de Reus (study approval no. 074/2018). Measurements were performed using a FlavourSpec® GC-IMS instrument equipped with a non-polar capillary GC column (FS-SE-54-CB). Ionization was achieved using a tritium β-radiation source and ion mobility separation was carried out in a drift tube operated under a constant electric field. Headspace sampling was conducted with an automated PAL-xt autosampler after thermal incubation of the sealed vials. Nitrogen was used both as carrier and drift gas. Volatile compounds were separated chromatographically before entering the ionization region and subsequently resolved in the ion mobility drift tube according to their mobility. Each measurement produced a two-dimensional signal matrix in which the axes correspond to gas-chromatographic retention time and ion mobility drift time, respectively. Signal intensity values represent the recorded ion current detected by a Faraday plate. Spectra were acquired in positive ion mode with temporal averaging of scans during acquisition. A blank measurement was performed after each sample to minimise carry-over and confirm recovery of the reactant ion peak. Each dataset entry corresponds to a full GC-IMS measurement lasting approximately 32 minutes. The resulting matrices contain roughly 22 million intensity values per measurement. Although the full retention-time range is preserved in the original files provided in this repository, subsequent data processing and analysis focus on the chromatographic region up to approximately 23 minutes of retention time. This truncation of the retention-time axis is applied during data processing using the GCIMS software package. In addition to the raw measurement files, the repository also includes a CSV file containing the inverse reactant ion peak (RIP) chromatograms extracted from the GC-IMS data within the retention-time range of approximately 0–23 minutes. These processed signals may facilitate rapid testing and benchmarking of chromatographic alignment algorithms without requiring full reconstruction of the two-dimensional data matrices. These data can be used for the development and evaluation of algorithms for chromatographic alignment, preprocessing, peak detection, chemometric analysis, and other computational approaches relevant to GC-IMS data processing. The dataset is associated with a research study focused on chromatographic alignment methodologies. Additional information about file organisation, variable definitions, and preprocessing steps is provided in the accompanying documentation included in the repository.本数据集包含来自混合人体尿液样本的气相色谱-离子迁移谱（GC-IMS）检测数据，其生成旨在为针对GC-IMS数据的色谱对齐与信号处理方法的方法学研究提供支撑。 尿液样本采集自11名健康志愿者（5名女性、6名男性），收集其清晨空腹尿液，并在受控条件下进行混合。将混合后的样本分装至多份样品瓶中，冷冻保存直至检测。检测前，每份样品瓶需加入氯化钠以增强挥发性、内标溶液（2-癸酮，2-decanone）与盐酸，随后采用顶空GC-IMS对制备好的样本进行分析。本研究方案经雷乌斯医院伦理委员会批准（研究批准编号：074/2018）。 检测采用FlavourSpec® GC-IMS仪器完成，该仪器配备非极性毛细管气相色谱柱（FS-SE-54-CB）。电离过程通过氚β辐射源实现，离子迁移分离在恒定电场驱动的漂移管中进行。密封样品瓶经热孵育后，通过自动化PAL-xt自动进样器完成顶空采样。氮气同时用作载气与漂移气。挥发性化合物先经色谱分离后进入电离区，随后根据其迁移率在离子迁移漂移管中完成分离。 单次检测可生成二维信号矩阵，其坐标轴分别对应气相色谱保留时间与离子迁移漂移时间。信号强度值代表法拉第盘检测到的离子电流记录结果。检测过程采用正离子模式采集谱图，并对扫描结果进行时间平均。每完成一份样本检测后均进行空白校准，以最大限度减少残留污染，并验证反应离子峰的回收率。 数据集中的每个条目对应一次完整的GC-IMS检测，单次检测时长约32分钟。每份检测生成的矩阵约包含2200万个强度值。尽管本仓库提供的原始文件保留了完整的保留时间范围，但后续数据处理与分析仅聚焦于保留时间约0~23分钟的色谱区域。该保留时间轴的截断操作通过GCIMS软件包在数据处理阶段完成。 除原始检测文件外，本仓库还包含一个CSV文件，其中存储了从约0~23分钟保留时间范围内的GC-IMS数据中提取的反相反应离子峰（reactant ion peak, RIP）色谱图。这些经过处理的信号可无需重建完整二维数据矩阵，即可快速测试与基准测试色谱对齐算法。 本数据集可用于开发与评估色谱对齐、预处理、峰检测、化学计量学分析及其他与GC-IMS数据处理相关的计算算法。 本数据集与一项聚焦于色谱对齐方法学的研究相关。仓库附带的文档中提供了关于文件组织、变量定义与预处理步骤的额外信息。