Department of Mechanical Engineering, School of Mechanical, Aerospace and Nuclear Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Korea.
Department of Biomedical Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Korea.
Sensors (Basel). 2017 Nov 11;17(11):2597. doi: 10.3390/s17112597.
Although many studies concerning the detection of influenza virus have been published, a paper-based, label-free electrochemical immunosensor has never been reported. Here, we present a cost-effective, handmade paper-based immunosensor for label-free electrochemical detection of influenza virus H1N1. This immunosensor was prepared by modifying paper with a spray of hydrophobic silica nanoparticles, and using stencil-printed electrodes. We used a glass vaporizer to spray the hydrophobic silica nanoparticles onto the paper, rendering it super-hydrophobic. The super-hydrophobicity, which is essential for this paper-based biosensor, was achieved via 30-40 spray coatings, corresponding to a 0.39-0.41 mg cm coating of nanoparticles on the paper and yielding a water contact angle of 150° ± 1°. Stencil-printed carbon electrodes modified with single-walled carbon nanotubes and chitosan were employed to increase the sensitivity of the sensor, and the antibodies were immobilized via glutaraldehyde cross-linking. Differential pulse voltammetry was used to assess the sensitivity of the sensors at various virus concentrations, ranging from 10 to 10⁴ PFU mL, and the selectivity was assessed against MS2 bacteriophages and the influenza B viruses. These immunosensors showed good linear behaviors, improved detection times (30 min), and selectivity for the H1N1 virus with a limit of detection of 113 PFU mL, which is sufficiently sensitive for rapid on-site diagnosis. The simple and inexpensive methodologies developed in this study have great potential to be used for the development of a low-cost and disposable immunosensor for detection of pathogenic microorganisms, especially in developing countries.
虽然已经发表了许多关于流感病毒检测的研究，但从未有过基于纸质、无标签的电化学免疫传感器的报道。在这里，我们提出了一种经济有效的、手工制作的基于纸张的无标签电化学免疫传感器，用于流感病毒 H1N1 的检测。该免疫传感器是通过用喷雾状的疏水性二氧化硅纳米粒子修饰纸张，并使用模板印刷电极来制备的。我们使用玻璃蒸发器将疏水性二氧化硅纳米粒子喷雾到纸张上，使纸张具有超疏水性。这种基于纸张的生物传感器所必需的超疏水性是通过 30-40 次喷雾涂层实现的，相当于在纸张上涂覆 0.39-0.41 毫克/平方厘米的纳米粒子，得到的水接触角为 150°±1°。使用经过单壁碳纳米管和壳聚糖修饰的模板印刷碳电极来提高传感器的灵敏度，并通过戊二醛交联将抗体固定化。使用差分脉冲伏安法评估了传感器在 10 到 10⁴ PFU mL 之间的不同病毒浓度下的灵敏度，并且评估了对 MS2 噬菌体和乙型流感病毒的选择性。这些免疫传感器表现出良好的线性行为、改进的检测时间（30 分钟）和对 H1N1 病毒的选择性，检测限为 113 PFU mL，对于快速现场诊断具有足够的灵敏度。本研究中开发的简单且廉价的方法学具有很大的潜力，可用于开发用于检测致病微生物的低成本和一次性免疫传感器，特别是在发展中国家。
