College of Chemistry and Material Science, Key Laboratory of Agricultural Film Application of Ministry of Agriculture and Rural Affairs, Food Safety Analysis and Test Engineering Technology Research Center of Shandong Province, Shandong Agricultural University, 271018, Taian, Shandong, People's Republic of China.
College of Chemistry and Material Science, Key Laboratory of Agricultural Film Application of Ministry of Agriculture and Rural Affairs, Food Safety Analysis and Test Engineering Technology Research Center of Shandong Province, Shandong Agricultural University, 271018, Taian, Shandong, People's Republic of China.
Anal Chim Acta. 2023 Apr 22;1251:341011. doi: 10.1016/j.aca.2023.341011. Epub 2023 Feb 25.
As an important epigenetic modification, 5-carboxycytosine (5caC) played an important role in gene regulation, cell differentiation and growth. 5caC existed in many cells and tissues, but it was highly similar to the structure of other cytosine derivatives and had less content in the genome. Therefore, it was urgent to develop a sensitive and highly selective trace biosensor to detect 5caC. A novel photoelectrochemical biosensor was fabricated for 5-carboxy-2'-deoxycytidine-5'-triphosphate (5cadCTP) detection, where SnS@TiC nanocomposite was employed as photoactive material, polyethyleneimine was used as 5cadCTP recognition and capture reagent, and Ru(NH) was used as photosensitizer for signal amplification. Due the good conductivity of TiC MXene and the matched energy band between TiC MXene and SnS, SnS@TiC nanocomposite presented strong photoactivity, which was beneficial to the high detection sensitivity. For specific recognition of 5cadCTP, the covalent interaction of -NH in 5cadCTP with -COOH on the substrate electrode was used, which was beneficial to the high detection selectivity. A broad linear relationship between photocurrent and 5cadCTP concentration was observed ranging from 1 pM to 0.2 μM. The low detection limit of 260 fM was achieved. The developed method has high detection specificity and can even distinguish 5caC with its derivatives. In addition, the applicability was evaluated by detecting the content change of 5caC in the genomic DNA of rice seedlings after cultured with environmental pollutants. This work provides a novel platform for 5cadCTP detection, and it can also be applied to detect other cytosine derivatives with suitable recognition strategies.
作为一种重要的表观遗传修饰，5-羧基胞嘧啶（5caC）在基因调控、细胞分化和生长中发挥着重要作用。5caC 存在于许多细胞和组织中，但它与其他胞嘧啶衍生物的结构高度相似，在基因组中的含量较少。因此，迫切需要开发一种灵敏且高选择性的痕量生物传感器来检测 5caC。本研究构建了一种用于 5-羧基-2'-脱氧胞苷-5'-三磷酸（5cadCTP）检测的光电化学生物传感器，其中 SnS@TiC 纳米复合材料作为光活性材料，聚乙烯亚胺作为 5cadCTP 的识别和捕获试剂，钌（Ⅱ）联吡啶配合物作为信号放大的光敏剂。由于 TiC MXene 的良好导电性和 TiC MXene 与 SnS 之间匹配的能带结构，SnS@TiC 纳米复合材料表现出较强的光活性，有利于获得高的检测灵敏度。对于 5cadCTP 的特异性识别，利用 5cadCTP 中的-NH 与基底电极上的-COOH 之间的共价相互作用，有利于获得高的检测选择性。在 1 pM 到 0.2 μM 的范围内观察到光电流与 5cadCTP 浓度之间呈现出宽的线性关系，检测限低至 260 fM。所开发的方法具有高的检测特异性，甚至可以区分 5caC 与其衍生物。此外，通过检测经环境污染物培养后的水稻幼苗基因组 DNA 中 5caC 含量的变化，评估了该方法的适用性。这项工作为 5cadCTP 的检测提供了一个新的平台，并且可以通过使用合适的识别策略来检测其他的胞嘧啶衍生物。
