School of Environmental and Safety Engineering, School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013, PR China.
School of Pharmacy, Jiangsu University, Zhenjiang 212013, PR China.
Spectrochim Acta A Mol Biomol Spectrosc. 2022 Mar 5;268:120622. doi: 10.1016/j.saa.2021.120622. Epub 2021 Nov 18.
Citrate is a tricarboxylate, plays vital role in prostate cancer (PC) and the level of citrate is an indicator for PC identification. Herein, triaminoguanidine carbon dots (TAG-CDs) prepared by one step hydrothermal method and used as a citrate receptor. Notably the TAG-CDs without alkaline treatment were highly fluorescent at pH 7 with high quantum yield (11.3%). TAG-CDs were characterized through TEM, XRD, FT-IR, UV-vis and spectrofluorimetry. It is noted that the average size was of 2.8 nm, the presence of highly disordered carbon, retain the functionality of TAG. The absorbance maxima obtained at 294 nm and good emitting response observed at 396 nm. The Y-aromaticity of receptor guanidinium moiety acts as Lewis acid and have peculiar interaction with Lewis base citrate via electrostatic interaction and also protons in the TAG participate hydrogen bonds with citrate, which causes quenching of TAG-CDs. From the obtained linear quenching equation the LOD was found to be 4 nM. The probe expressed high selectivity, high interference tolerance (500 - fold), fast response in 15 mins and good biocompatible. Finally, TAG-CDs utilized for the intracellular imaging of citrate in live MCF-7 cells, it showed good cytotoxicity and delivered contrast images in presence, absence of citrate. TAG-CDs detected the citrate level in human urine samples, the obtained results are validated with HPLC method.
柠檬酸盐是一种三羧酸，在前列腺癌（PC）中起着重要作用，柠檬酸盐的水平是 PC 鉴定的一个指标。在此，通过一步水热法制备了三氨基胍碳点（TAG-CDs），并用作柠檬酸盐受体。值得注意的是，未经碱性处理的 TAG-CDs 在 pH 7 时具有高荧光性，量子产率（11.3%）很高。通过 TEM、XRD、FT-IR、UV-vis 和荧光光谱法对 TAG-CDs 进行了表征。值得注意的是，平均尺寸为 2.8nm，存在高度无序的碳，保留了 TAG 的功能性。在 294nm 处获得的吸收最大值和在 396nm 处观察到的良好发射响应。受体胍基部分的 Y-芳构性作为路易斯酸，通过静电相互作用与柠檬酸盐具有特殊的相互作用，并且 TAG 中的质子与柠檬酸盐形成氢键，这导致 TAG-CDs 猝灭。从获得的线性猝灭方程中发现 LOD 为 4nM。该探针表现出高选择性、高干扰容忍度（500 倍）、在 15 分钟内快速响应和良好的生物相容性。最后，TAG-CDs 用于活 MCF-7 细胞中柠檬酸盐的细胞内成像，在存在和不存在柠檬酸盐的情况下均显示出良好的细胞毒性和对比度图像。TAG-CDs 检测了人尿样中的柠檬酸盐水平，所得结果用 HPLC 法进行了验证。
