Abstract：
The volume of blood leaked from blood vessels may change due to evaporation of water under the natural influence of the external environment. Bloodstains and dried blood spots (DBS), which describes blood dried in the external environment, are similar in their production and their metabolite quantification profiles. In both bloodstain metabolite analysis in the forensic science field and DBS metabolite analysis in the clinical field, it is important to determine the volume of the origin blood as this affects metabolite quantification results. Therefore, the purpose of this study is to discover the internal standard metabolites that have quantitatively proportional relationships with origin blood volume and maintain constant concentrations even as the age of the bloodstain increases. As a result, the concentrations of L-isoleucine and L-phenylalanine increased in proportion to the origin blood volume of the bloodstain. The differences in concentration of L-isoleucine were significant in all volume comparisons except in the comparison between 65 μL and 85 μL. The differences in concentration of L-phenylalanine were significant in all volume comparisons except between 65 μL and 45 μL and between 65 μL and 85 μL. In addition, it was confirmed that both metabolites tended to maintain constant concentrations without being affected by bloodstain age as the volume became smaller. These internal standard metabolites can be used for estimating the origin blood volume of bloodstains during metabolite analysis of bloodstains and DBS and could provide a volume criterion for standardization when comparing metabolite quantification between samples.
摘要：
在外部环境的自然影响下，由于水的蒸发，从血管泄漏的血液量可能会发生变化。血迹和干血斑（DBS），描述了血液在外部环境中干燥，它们的产量和代谢物定量曲线相似。在法医学领域的血迹代谢物分析和临床领域的DBS代谢物分析中，重要的是确定血液来源的体积，因为这会影响代谢物的定量结果。因此,这项研究的目的是发现内标代谢产物，这些代谢产物与血量呈定量比例关系，即使随着血迹年龄的增加也能保持恒定的浓度。因此,L-异亮氨酸和L-苯丙氨酸的浓度与血迹来源的血容量成比例增加。除了在65μL和85μL之间的比较之外,在所有体积比较中,L-异亮氨酸的浓度差异是显著的。除了在65μL和45μL之间以及在65μL和85μL之间,在所有体积比较中L-苯丙氨酸的浓度差异是显著的。此外,已证实，随着体积变小，两种代谢物倾向于保持恒定的浓度，而不受血迹年龄的影响。这些内标代谢物可用于在血迹和DBS的代谢物分析期间估计血迹的起源血体积，并且可以在比较样品之间的代谢物定量时提供标准化的体积标准。
