Infection Medicine, Edinburgh Medical School, College of Medicine and Veterinary Medicine, The University of Edinburgh, Chancellor's Building, 49 Little France Crescent, Edinburgh EH16 4SB, UK.
Polymer and Biomaterials Chemistry Laboratories, School of Chemistry and Biosciences, University of Bradford, Bradford BD7 1DP, UK.
Sensors (Basel). 2021 Mar 8;21(5):1872. doi: 10.3390/s21051872.
Rapid point of care tests for bacterial infection diagnosis are of great importance to reduce the misuse of antibiotics and burden of antimicrobial resistance. Here, we have successfully combined a new class of non-biological binder molecules with electrochemical impedance spectroscopy (EIS)-based sensor detection for direct, label-free detection of Gram-positive bacteria making use of the specific coil-to-globule conformation change of the vancomycin-modified highly branched polymers immobilized on the surface of gold screen-printed electrodes upon binding to Gram-positive bacteria. was detected after just 20 min incubation of the sample solution with the polymer-functionalized electrodes. The polymer conformation change was quantified with two simple 1 min EIS tests before and after incubation with the sample. Tests revealed a concentration dependent signal change within an OD range of from 0.002 to 0.1 and a clear discrimination between Gram-positive and Gram-negative bacteria. This exhibits a clear advancement in terms of simplified test complexity compared to existing bacteria detection tests. In addition, the polymer-functionalized electrodes showed good storage and operational stability.
快速即时的医疗点细菌感染诊断检测对于减少抗生素的滥用和对抗微生物药物耐药性的负担具有重要意义。在这里，我们成功地将一类新型非生物结合分子与基于电化学阻抗谱（EIS）的传感器检测相结合，利用万古霉素修饰的高度支化聚合物在结合到金丝网印刷电极表面上后，其特定的从线圈到球的构象变化，实现了对革兰氏阳性菌的直接、无标记检测。在与聚合物功能化电极孵育 20 分钟后，仅检测到 。通过在孵育前后进行两次简单的 1 分钟 EIS 测试，对聚合物构象变化进行了定量。测试结果显示，在 OD 值范围为 0.002 至 0.1 内，信号变化与浓度呈依赖关系，并且可以清楚地区分革兰氏阳性菌 和革兰氏阴性菌 。与现有的细菌检测试验相比，这在简化试验复杂性方面取得了明显的进展。此外，聚合物功能化电极显示出良好的储存和操作稳定性。
