The purpose of the present study is to develop an easy and effective one-step pyrolytic method for synthesizing carbon dots (CDs) derived from folic acid (FA), denoted herein as FACDs. This method is green, inexpensive, and simplifies the synthesis of fluorescent carbon nanomaterials with enhanced and stable fluorescence. Moreover, the as-prepared FACDs are effective in the sensitive and selective detection of cysteine (Cys) by such a “turn-on” mechanism of fluorescence. FACDs have been able to realize a low detection limit of 1.7 × 10⁻⁷ M and a wide linear range from 5.0 × 10⁻⁷ to 8.0 × 10⁻⁵ M, successfully restoring quenched fluorescence in the presence of Cys. Obtained results confirm FACDs as a trustful high-performance sensor for various biological and environmental applications and pave the way for facile and efficient fluorescence-based detection platforms.

中文翻译：

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叶酸衍生碳点的绿色一步热解合成，用于半胱氨酸的灵敏开启荧光检测


本研究的目的是开发一种简单有效的一步热解方法，用于合成叶酸 （FA） 衍生的碳点 （CD），本文称为 FACD。这种方法绿色、廉价，并且简化了荧光碳纳米材料的合成，具有增强和稳定的荧光。此外，所制备的 FACDs 通过这种荧光的“开启”机制有效地对半胱氨酸 （Cys） 进行灵敏和选择性的检测。FACD 已经能够实现 1.7 × ^10-7 M 的低检测限和从 5.0 × ^10-7 到 8.0 × ^10-5 M 的宽线性范围，成功地在 Cys 存在下恢复了淬灭荧光。获得的结果证实 FACD 是适用于各种生物和环境应用的可靠高性能传感器，并为简单高效的基于荧光的检测平台铺平了道路。