College of Ocean Food and Biological Engineering, Jimei University, Fujian Provincial Key Laboratory of Food Microbiology and Enzyme Engineering, 361021, Xiamen, PR China.
College of Ocean Food and Biological Engineering, Jimei University, Fujian Provincial Key Laboratory of Food Microbiology and Enzyme Engineering, 361021, Xiamen, PR China; College of Chemistry and Molecular Sciences, Wuhan University, 430072, Wuhan, PR China.
Anal Chim Acta. 2023 Apr 29;1252:341048. doi: 10.1016/j.aca.2023.341048. Epub 2023 Mar 4.
Adenosine triphosphate (ATP), the main carrier of chemical energy, plays a key role in various biochemical reactions such as cellular metabolism. Currently, ATP levels are considered important indicators of microbial content in food safety, and food freshness can be determined by detecting ATP content. Some ATP sensing strategies have been applied to evaluate food freshness. However, cumbersome nanomaterial preparation, low sensitivity, and low reliability hamper their widespread application. Herein, a simple, high-performance, and reliable dual-mode sensing system based on hemin-G-quadruplex (G4) DNAzyme was established to detect ATP and assess fish freshness. Two nucleic acid probes, including subunits of the hemin-G4 DNAzyme in inactive structures and anti-ATP aptamer, self-assemble upon the input of ATP into the active hemin-G4 DNAzyme unit. The generated DNAzyme acts as a biocatalyst for colorimetric or fluorescent readout of the sensing process. The colorimetric and fluorescent dual-mode sensing system enables highly sensitive and reliable analysis of target ATP with detection limits of 71 nM and 73 nM, respectively. Moreover, the biosensor exhibited good selectivity for differentiating ATP from other interfering analytes. The proposed system was used to detect ATP in perch samples, and a linear correlation between ATP level and microbial content was confirmed. The established ATP-sensing system reliably evaluated fish freshness. Notably, in comparison with microbiological counts, the proposed DNAzyme-based dual-mode strategy for freshness evaluation is facile, highly efficient, and cost-effective, thus providing a promising method for food safety and quality monitoring.
三磷酸腺苷（ATP）是化学能的主要载体，在细胞代谢等各种生化反应中发挥关键作用。目前，ATP 水平被认为是食品安全中微生物含量的重要指标，可以通过检测 ATP 含量来确定食品的新鲜度。一些 ATP 传感策略已被应用于评估食品的新鲜度。然而，繁琐的纳米材料制备、低灵敏度和低可靠性限制了它们的广泛应用。在此，建立了一种基于血红素-G-四链体（G4）DNA zyme 的简单、高性能和可靠的双模式传感系统，用于检测 ATP 和评估鱼类的新鲜度。两个核酸探针，包括无活性结构的血红素-G4 DNAzyme 亚基和抗-ATP 适体，在输入 ATP 后自组装到活性血红素-G4 DNAzyme 单元中。生成的 DNAzyme 作为生物催化剂，用于比色或荧光读出传感过程。比色和荧光双模式传感系统能够对目标 ATP 进行高灵敏度和可靠的分析，检测限分别为 71 nM 和 73 nM。此外，该生物传感器对区分 ATP 和其他干扰分析物具有良好的选择性。该系统用于检测鲈鱼样品中的 ATP，并证实 ATP 水平与微生物含量之间存在线性关系。所建立的 ATP 传感系统可靠地评估了鱼类的新鲜度。值得注意的是，与微生物计数相比，基于 DNAzyme 的双模式策略用于新鲜度评估更加简便、高效且具有成本效益，为食品安全和质量监测提供了一种有前途的方法。
