Zhu Dongwei, Dai Jindong, Jia Jue, Kanagaraj Thangamani, Rajalakshmi Kanagaraj, Muthusamy Selvaraj, Geng Lina, Yuan Guoyue
Department of Endocrinology and Metabolism, The Affiliated Hospital of Jiangsu University; Institute of Endocrine and Metabolic Diseases, Jiangsu University, Zhenjiang 212013, PR China.
Department of Immunology, Jiangsu Key Laboratory of Laboratory Medicine, School of Medicine, and School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013, PR China.
Spectrochim Acta A Mol Biomol Spectrosc. 2025 Mar 15;329:125568. doi: 10.1016/j.saa.2024.125568. Epub 2024 Dec 14.
Citrate is a potential biomarker for early stage detection of prostate cancer (PC), its concentration significantly dropped to 2-20 mM in PC patients. Herein, a cheap, simple, and reliable citrate sensor was proposed based on the biogenic synthesis of nitrogen-doped carbon dots (N-CDs) derived from the biowaste of Syzygiumcumini (S. cumini) seeds. The prepared N-CDs were characterized by TEM, FT-IR and spectral studies. The average size of the N-CDs was found to be 2.4 nm, the presence of -OH and -NH functional groups on the surface of N-CDs was confirmed by FT-IR analysis. The N-CDs possess the highest emission at 414 nm and cause quenching after reacting with citrate, which is due to the possible hydrogen bonding interactions between the probe and citrate. The probe expressed the lowest limit of detection of 3.5 nM, high selectivity, high interfering ability (1000-fold), provided a stable response at 5 min of reaction time, good biocompatibility, and delivered a contrast bioimage with different concentrations of citrate. The N-CDs were utilized to detect citrate in human urine samples, obtained good recovery results, and validated with the high-performance liquid chromatography method.
柠檬酸盐是前列腺癌（PC）早期检测的潜在生物标志物，其浓度在PC患者中显著降至2 - 20 mM。在此，基于从蒲桃（S. cumini）种子的生物废料中生物合成氮掺杂碳点（N - CDs），提出了一种廉价、简单且可靠的柠檬酸盐传感器。通过透射电子显微镜（TEM）、傅里叶变换红外光谱（FT - IR）和光谱研究对制备的N - CDs进行了表征。发现N - CDs的平均尺寸为2.4 nm，FT - IR分析证实了N - CDs表面存在 - OH和 - NH官能团。N - CDs在414 nm处具有最高发射，与柠檬酸盐反应后会发生猝灭，这是由于探针与柠檬酸盐之间可能存在氢键相互作用。该探针的最低检测限为3.5 nM，具有高选择性、高抗干扰能力（1000倍），在反应5分钟时提供稳定响应，具有良好的生物相容性，并能呈现不同浓度柠檬酸盐的对比生物图像。利用N - CDs检测人尿液样本中的柠檬酸盐，获得了良好的回收率结果，并用高效液相色谱法进行了验证。
