Recently, nanozymes have become a topic of particular interest due to their high activity level, stability and biocompatibility. In this study, a visual, sensitive and selective point-of-care immunosensor was established to test the pathogen Escherichia coli O157:H7 (E. coli O157:H7). Hemin and magainin I (MI) hybrid nanocomposites (Hemin@MI) with peroxidase-mimicking activities were synthesized via a “one-pot” method, involving the simple mixing of an antimicrobial peptide (MI) against E. coli O157:H7 and hemin in a copper sulfate sodium phosphate saline buffer. Hemin@MI nanocomposites integrating target recognition and signal amplification were developed as signal probes for the point-of-care colorimetric detection of pathogenic E. coli O157:H7. Hemin@MI nanocomposites exhibit excellent peroxidase activity for the chromogenic reaction of ABTS, which allows for the visual point-of-care testing of E. coli O157:H7 in the range of 10² to 10⁸ CFU/mL, with a limit of detection of 85 CFU/mL. These data suggest this immunosensor provides accessible and portable assessments of pathogenic E. coli O157:H7 in real samples.

最近，纳米酶因其高活性水平、稳定性和生物相容性而成为一个特别感兴趣的话题。在这项研究中，建立了一种视觉、灵敏和选择性的即时免疫传感器来测试病原体大肠杆菌O157:H7（E.coli O157:H7）。具有过氧化物酶模拟活性的 Hemin 和 magainin I (MI) 混合纳米复合材料 (Hemin@MI)通过“一锅法”合成，包括简单混合抗大肠杆菌O157:H7 和 hemin的抗菌肽 (MI)在硫酸铜磷酸钠盐水缓冲液中。将目标识别和信号放大相结合的 Hemin@MI 纳米复合材料被开发为用于病原菌即时比色检测的信号探针大肠杆菌O157:H7。Hemin@MI 纳米复合材料对 ABTS 的显色反应表现出优异的过氧化物酶活性，允许在 10 ²至 10 ⁸ CFU/mL范围内对大肠杆菌O157:H7 进行目视即时检测，限值为85 CFU/mL 的检测。这些数据表明，该免疫传感器提供了对真实样本中致病性大肠杆菌O157:H7 的可访问和便携式评估。