In this work, we proposed one simple and effective chiral-sensing method for the discrimination of carnitine enantiomers. The gold nanorods (AuNRs) were used as colorimetric probes to recognize carnitine enantiomers in this method. l-Carnitine can induce rapidly the blue-to-gray change of AuNR solution color, whereas d-carnitine cannot induce the obvious change of the color. Based on this distinct difference of color, a visual method for recognition of carnitine enantiomers was suggested. This method has been applied to detect the enantiometric excess of l-carnitine in the range of − 100~100%. The presented chiral measurement can be performed with a simple ultraviolet-visible spectrometer and even the naked eyes. In this method, AuNRs need no modification with chiral molecule, and the chiral recognition is based on the inherent chirality of AuNRs. This new method opens up possibility for fast and easy assay of carnitine enantiomers. Graphical abstract Graphical abstract

中文翻译：

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金纳米棒作为肉碱对映体肉眼识别的比色探针

在这项工作中，我们提出了一种简单有效的手性传感方法来鉴别肉碱对映体。在该方法中，金纳米棒 (AuNRs) 被用作比色探针来识别肉碱对映体。左旋肉碱能迅速诱导AuNR溶液颜色由蓝变灰，而d-肉碱不能诱导明显的颜色变化。基于这种明显的颜色差异，提出了一种识别肉碱对映体的视觉方法。该方法已用于检测-100~100%范围内的左旋肉碱对映过量。所提出的手性测量可以使用简单的紫外-可见光谱仪甚至肉眼进行。在该方法中，AuNRs 不需要用手性分子进行修饰，手性识别是基于 AuNRs 的固有手性。这种新方法为快速简便地测定肉碱对映体开辟了可能性。图形摘要图形摘要