At present, there is a lack of sufficiently specific laboratory diagnostic indicators for schizophrenia. Serum homocysteine (Hcy) levels have been found to be related to schizophrenia. Cysteine (Cys) is a demethylation product in the metabolism of Hcy, and they always coexist with highly similar structures in vivo. There are few reports on the use of Cys as a diagnostic biomarker for schizophrenia in collaboration with Hcy, mainly because the rapid, economical, accurate, and high-throughput simultaneous detection of Cys and Hcy in serum is highly challenging. Herein, a click reaction-based surface-enhanced Raman spectroscopy (SERS) sensor was developed for simultaneous and selective detection of Cys and Hcy. Through the efficient and specific CBT-Cys click reaction between the probe containing cyan benzothiazole and Cys/Hcy, the tiny methylene difference between the molecular structures of Cys and Hcy was converted into the difference between the ring skeletons of the corresponding products that could be identified by plasmonic silver nanoparticle enhanced molecular fingerprint spectroscopy to realize discriminative detection. Furthermore, the SERS sensor was successfully applied to the detection in related patient serum samples, and it was found that the combined analysis of Cys and Hcy can improve the diagnostic accuracy of schizophrenia compared to a single indicator.

中文翻译：

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基于 CBT-Cys 点击反应同时 SERS 传感血液中的半胱氨酸和同型半胱氨酸：迈向精神分裂症的精确诊断

目前，精神分裂症缺乏足够特异性的实验室诊断指标。已发现血清同型半胱氨酸（Hcy）水平与精神分裂症有关。半胱氨酸（Cys）是Hcy代谢过程中的去甲基化产物，它们在体内总是以高度相似的结构共存。将Cys与Hcy联合用作精神分裂症诊断生物标志物的报道很少，主要是因为快速、经济、准确、高通量同时检测血清中Cys和Hcy具有很大的挑战性。在此，开发了一种基于点击反应的表面增强拉曼光谱 (SERS) 传感器，用于同时选择性检测 Cys 和 Hcy。通过含氰基苯并噻唑的探针与Cys/Hcy之间高效、特异的CBT-Cys点击反应，将Cys和Hcy分子结构之间微小的亚甲基差异转化为可识别的相应产物的环骨架差异通过等离子体银纳米颗粒增强分子指纹光谱实现判别检测。此外，SERS传感器成功应用于相关患者血清样本的检测，发现Cys和Hcy联合分析较单一指标可以提高精神分裂症的诊断准确性。