Faleke H O, Pappas D
Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX, 79409 - 1061, USA.
Anal Bioanal Chem. 2025 Jun;417(15):3435-3446. doi: 10.1007/s00216-025-05876-2. Epub 2025 Apr 16.
Histidine-derived carbon dots (His-CDs) were synthesized to detect staurosporine-induced apoptosis in T lymphoma (Jurkat) cells. The His-CDs were characterized for their physical and chemical properties including size, morphology, fluorescence, and surface functionality. Transmission electron microscopy (TEM) revealed a spherical morphology with an average size of 11.4 ± 3.4 nm. Fluorescence analysis showed maximum excitation at 338 nm and emission at 415 nm, attributed to the carbon dots' quantum confinement effect and surface defects. FTIR and SEM-EDS confirmed the presence of hydroxyl, amine, aromatic rings, and alkyl (C-H) functional groups and carbon, nitrogen, and oxygen elemental composition in ratios of 52%, 24.8%, and 23.3%, respectively. His-CDs were evaluated for cytotoxicity and apoptosis detection in Jurkat cells. Fluorescence microscopy and flow cytometry analysis demonstrated concentration-dependent fluorescence, suggesting effective cellular uptake of His-CDs. The apoptotic-sensing capability of His-CDs was tested using staurosporine, an apoptosis inducer. A concentration-dependent increase in fluorescence was observed with increasing staurosporine concentrations, indicating the His-CDs' sensitivity to apoptosis. The time-dependent fluorescence increases were noted with prolonged staurosporine exposure. Z-DEVD-FMK, a caspase-3 inhibitor, confirmed that the apoptosis detected by His-CDs was caspase-3 dependent, as co-treatment reduced His-CDs' fluorescence in the cell. In conclusion, these results demonstrate that His-CDs are biocompatible, sensitive apoptosis sensors and hold the potential for monitoring apoptotic pathways in cellular systems.
合成了组氨酸衍生的碳点（His-CDs）以检测星形孢菌素诱导的T淋巴瘤（Jurkat）细胞凋亡。对His-CDs的物理和化学性质进行了表征，包括尺寸、形态、荧光和表面功能。透射电子显微镜（TEM）显示其呈球形形态，平均尺寸为11.4±3.4 nm。荧光分析表明，其在338 nm处有最大激发波长，在415 nm处有发射波长，这归因于碳点的量子限制效应和表面缺陷。傅里叶变换红外光谱（FTIR）和扫描电子显微镜-能谱分析（SEM-EDS）证实了羟基、胺基、芳香环和烷基（C-H）官能团的存在，以及碳、氮和氧元素的组成比例分别为52%、24.8%和23.3%。对His-CDs在Jurkat细胞中的细胞毒性和凋亡检测进行了评估。荧光显微镜和流式细胞术分析显示出浓度依赖性荧光，表明His-CDs能有效被细胞摄取。使用凋亡诱导剂星形孢菌素测试了His-CDs的凋亡传感能力。随着星形孢菌素浓度的增加，观察到荧光呈浓度依赖性增加，表明His-CDs对凋亡敏感。随着星形孢菌素暴露时间的延长，荧光随时间增加。caspase-3抑制剂Z-DEVD-FMK证实，His-CDs检测到的凋亡是caspase-3依赖性的，因为联合处理降低了细胞中His-CDs的荧光。总之，这些结果表明His-CDs是生物相容性良好、敏感的凋亡传感器，具有监测细胞系统中凋亡途径的潜力。
