Advanced Biomaterials and Tissue Engineering Center, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, China.
Department of Pulp & Paper Engineering, College of Light Industry and Food Engineering, Nanjing Forestry University, Nanjing 210037, China.
Biosensors (Basel). 2024 Oct 14;14(10):500. doi: 10.3390/bios14100500.
The rapid and sensitive detection of in food matrices is crucial for ensuring food safety. This study presents the development of an ultrasensitive electrochemical biosensor using surface-modified bacterial cellulose (BC) integrated with polypyrrole (Ppy) and reduced graphene oxide (RGO), further functionalized with immobilized -specific phage particles. The BC substrate, with its ultra-fibrous and porous structure, was modified through in situ oxidative polymerization of Ppy and RGO, resulting in a highly conductive and flexible biointerface. The immobilization of phages onto this composite was facilitated by electrostatic interactions between the polycationic Ppy and the negatively charged phage capsid heads, optimizing phage orientation and enhancing bacterial capture efficiency. Morphological and chemical characterization confirmed the successful fabrication and phage immobilization. The biosensor demonstrated a detection limit of 1 CFU/mL for in phosphate-buffered saline (PBS), with a linear detection range spanning 10 to 10 CFU/mL. In real samples, the sensor achieved detection limits of 5 CFU/mL in milk and 3 CFU/mL in chicken, with a linear detection range spanning 10 to 10 CFU/mL, maintaining high accuracy and reproducibility. The biosensor also effectively discriminated between live and dead bacterial cells, demonstrating its potential in real-world food safety applications. The biosensor performed excellently over a wide pH range (4-10) and remained stable for up to six weeks. Overall, the developed BC/Ppy/RGO-phage biosensor offers a promising tool for the rapid, sensitive, and selective detection of , with robust performance across different food matrices.
在食物基质中快速灵敏地检测 对于确保食品安全至关重要。本研究提出了一种基于表面修饰的细菌纤维素（BC）的超灵敏电化学生物传感器的开发，该传感器与聚吡咯（Ppy）和还原氧化石墨烯（RGO）集成，并进一步功能化固定化的 - 特异性噬菌体颗粒。BC 基底具有超纤维和多孔结构，通过原位氧化聚合 Ppy 和 RGO 进行修饰，形成了高导电性和柔性的生物界面。噬菌体通过聚阳离子 Ppy 与带负电荷的噬菌体衣壳头部之间的静电相互作用固定在该复合材料上，优化了噬菌体的取向并提高了细菌捕获效率。形态和化学特性表征证实了成功的制造和噬菌体固定化。该生物传感器在磷酸盐缓冲盐水（PBS）中对 的检测限为 1 CFU/mL，线性检测范围为 10 至 10 CFU/mL。在实际样品中，该传感器在牛奶中的检测限为 5 CFU/mL，在鸡肉中的检测限为 3 CFU/mL，线性检测范围为 10 至 10 CFU/mL，保持了高准确性和重现性。该传感器还能有效区分活菌和死菌细胞，显示出其在实际食品安全应用中的潜力。该生物传感器在宽 pH 范围（4-10）下表现出色，并且稳定长达六周。总的来说，开发的 BC/Ppy/RGO-噬菌体生物传感器为快速、灵敏、选择性检测 提供了一种有前途的工具，在不同的食物基质中具有稳健的性能。
