Wu Qianyue, Yang Beiying, Wang Yutang, Xiong Yanyan, Zhang Jinhua, Wen Yangping, Rajkovic Andreja
Institute of Animal Disease Prevent and Control, College of Animal Science and Technology, Jiangxi Agricultural University, Nanchang, 330045, China.
Institute of Functional Materials and Agricultural Applied Chemistry, College of Chemistry and Materials, Jiangxi Agricultural University, Nanchang, 330045, China.
Mikrochim Acta. 2025 Mar 28;192(4):264. doi: 10.1007/s00604-025-07126-9.
An accurate, sensitive, low-cost, portable, and easy-to-use method for the quantitative detection of Clostridium perfringens (Cp), a zoonotic pathogen widely found in nature and capable of spreading through contaminated food or environments, is essential for epidemiology, prevention, and diagnostics. Here, we have designed a smartphone-based electrochemical DNA biosensor, which utilizes carboxyl-functionalized multi-walled carbon nanotubes (COOH-MWCNTs) as the substrate, L-cysteine (L-Cys) as the linker, and a synergistic modification of the bioelectrode with gold nanoparticles (AuNPs) and polyamidoamine dendrimers (PAMAM). This design enables highly sensitive, low-cost, label-free, and portable detection of the cpb2 gene in Cp. The sensor not only enhances detection performance but also improves convenience and practicality. Differential pulse voltammetry (DPV) was used to monitor the electrochemical signal response to changes in target DNA concentration, enabling the tracking of the DNA hybridization process. Under optimized conditions, the biosensor exhibited a linear detection range from 10⁻ to 10⁻⁸ M, with a detection limit of 1.5 fM. It demonstrated excellent selectivity for the cpb2 gene and was successfully applied to detect variations in cpb2 gene content in wastewater and fecal DNA samples. Compared with the traditional method, the detection time of this method is short, the operation of professional and technical personnel is not required, the instrument is small and portable, and the single detection cost is significantly reduced. This study provides a new strategy for the rapid, portable, and highly sensitive detection of bacterial toxin genes in livestock and aquaculture.
产气荚膜梭菌（Cp）是一种在自然界广泛存在的人畜共患病原体，能够通过受污染的食物或环境传播。因此，一种准确、灵敏、低成本、便携式且易于使用的定量检测方法对于流行病学、预防和诊断至关重要。在此，我们设计了一种基于智能手机的电化学DNA生物传感器，该传感器以羧基功能化多壁碳纳米管（COOH-MWCNTs）为底物，L-半胱氨酸（L-Cys）为连接体，并通过金纳米颗粒（AuNPs）和聚酰胺胺树枝状大分子（PAMAM）对生物电极进行协同修饰。这种设计能够实现对Cp中cpb2基因的高灵敏度、低成本、无标记和便携式检测。该传感器不仅提高了检测性能，还提升了便利性和实用性。采用差分脉冲伏安法（DPV）监测电化学信号对目标DNA浓度变化的响应，从而跟踪DNA杂交过程。在优化条件下，该生物传感器的线性检测范围为10⁻¹²至10⁻⁸ M，检测限为1.5 fM。它对cpb2基因表现出优异的选择性，并成功应用于检测废水和粪便DNA样本中cpb2基因含量的变化。与传统方法相比，该方法检测时间短，无需专业技术人员操作，仪器小巧便携，单次检测成本显著降低。本研究为畜禽和水产养殖中细菌毒素基因的快速、便携式和高灵敏度检测提供了一种新策略。
