Untargeted metabolomic studies are used for large-scale analysis of endogenous compounds. Due to exceptional long detection windows of incorporated substances in hair, analysis of hair samples for retrospective monitoring of metabolome changes has recently been introduced. However, information on the general behavior of metabolites in hair samples is scarce, hampering correct data interpretation so far. The presented study aimed to investigate endogenous metabolites depending on hair color and along the hair strand and to propose recommendations for best practice in hair metabolomic studies. A metabolite selection was analyzed using untargeted data acquisition in genuine hair samples from different hair colors and after segmentation in 3 cm segments. Significant differences in metabolites among hair colors and segments were found. In conclusion, consideration of hair color and hair segments is necessary for hair metabolomic studies and, subsequently, recommendations for best practice in hair metabolomic studies were proposed.

中文翻译：

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迈向头发代谢组学研究的最佳实践：对头发长度和颜色影响的系统研究

非靶向代谢组学研究用于内源性化合物的大规模分析。由于头发中掺入物质的检测窗口非常长，因此最近引入了用于回顾性监测代谢组变化的头发样品分析方法。但是，关于头发样品中代谢物一般行为的信息很少，到目前为止，这妨碍了正确的数据解释。提出的研究旨在根据头发的颜色和沿发束的方向研究内源性代谢物，并为头发代谢组学研究的最佳实践提出建议。使用来自不同发色的真发样品以及在3 cm的分段中进行分段后，使用非目标数据采集来分析代谢物的选择。发现头发颜色和片段之间的代谢物存在显着差异。结论，