On-site discrimination of the most abundant low-molecular-weight biothiols including Cys, CysGly, Hcy and GSH in biological fluid is extremely valuable for diagnosing and dissecting various diseases. However, this remains a great challenge due to the very similar structure and reactive activity of the four biothiols. Herein, a novel fluorescent probe that is able to concurrently discriminate Cys, CysGly, Hcy and GSH in distinct fluorescence channel based on a new strategy of regulating the nucleophilic ability of amine group in Cys, CysGly, Hcy and GSH under distinct pH condition. Moreover, a portable fluorescence detection device that can on-site accurately quantify the fluorescence intensities in biological fluid has been rationally fabricated. The fluorescent probe in combination with the self-made portable fluorescence detection device has been successfully applied for on-site quantitative discrimination of Cys, CysGly, Hcy and GSH in biological fluids such as plasma and urine, which provides a quick and inexpensive way to screen and diagnose the biothiols related diseases as well as dissect their physiological and pathological processes.

现场鉴别生物体液中含量最丰富的低分子生物硫醇，包括Cys、CysGly、Hcy和GSH，对于诊断和解剖各种疾病非常有价值。然而，由于四种生物硫醇的结构和反应活性非常相似，这仍然是一个巨大的挑战。在此，基于在不同pH条件下调节Cys、CysGly、Hcy和GSH中胺基团的亲核能力的新策略，一种能够同时区分不同荧光通道中的Cys、CysGly、Hcy和GSH的新型荧光探针。此外，合理制造了一种可以现场准确量化生物体液中荧光强度的便携式荧光检测装置。