Institute of Microtechnology, Technische Universität Braunschweig, 38124 Braunschweig, Germany.
Lionex Diagnostics & Therapeutics GmbH, 38124 Braunschweig, Germany.
Biosensors (Basel). 2020 Sep 25;10(10):135. doi: 10.3390/bios10100135.
Infections with antimicrobial resistant bacteria are a rising threat for global healthcare as more and more antibiotics lose their effectiveness against bacterial pathogens. To guarantee the long-term effectiveness of broad-spectrum antibiotics, they may only be prescribed when inevitably required. In order to make a reliable assessment of which antibiotics are effective, rapid point-of-care tests are needed. This can be achieved with fast phenotypic microfluidic tests, which can cope with low bacterial concentrations and work label-free. Here, we present a novel optofluidic chip with a cross-flow immobilization principle using a regular array of nanogaps to concentrate bacteria and detect their growth label-free under the influence of antibiotics. The interferometric measuring principle enabled the detection of the growth of in under 4 h with a sample volume of 187.2 µL and a doubling time of 79 min. In proof-of-concept experiments, we could show that the method can distinguish between bacterial growth and its inhibition by antibiotics. The results indicate that the nanofluidic chip approach provides a very promising concept for future rapid and label-free antimicrobial susceptibility tests.
耐抗生素细菌感染对全球医疗保健构成了日益严重的威胁，因为越来越多的抗生素对细菌病原体失去了效力。为了保证广谱抗生素的长期有效性，只有在必需时才可以开这些抗生素。为了可靠地评估哪些抗生素有效，需要快速的即时检测。这可以通过快速表型微流控测试来实现，该测试可以应对低细菌浓度，并且无需标记即可工作。在这里，我们提出了一种新颖的光流控芯片，该芯片采用带有规则纳米间隙的横流固定化原理来浓缩细菌，并在抗生素的影响下无需标记即可检测其生长。干涉测量原理使我们能够在 4 小时内检测到 的生长，样品体积为 187.2µL，倍增时间为 79 分钟。在概念验证实验中，我们证明该方法可以区分细菌生长及其被抗生素抑制的情况。结果表明，该纳米流控芯片方法为未来快速、无需标记的抗生素药敏试验提供了一个非常有前景的概念。
