Eissa Shimaa, Al-Kattan Khaled, Zourob Mohammed
Department of Chemistry, Alfaisal University, Al Zahrawi Street, Al Maather, Al Takhassusi Road, Riyadh 11533, Saudi Arabia.
Department of Microbiology and Immunology, College of Medicine, Alfaisal University, Al Zahrawi Street, Al Maather, Al Takhassusi Road, Riyadh 11533, Saudi Arabia.
ACS Omega. 2021 Nov 16;6(47):32072-32080. doi: 10.1021/acsomega.1c04849. eCollection 2021 Nov 30.
The miniaturization of biosensors for point-of-care diagnosis is highly important in infection control. Electrochemical biosensors offer several advantages in diagnosis in terms of cost, disposability, portability, and sensitivity. Here, a miniaturized electrochemical immunosensor combined with cotton fiber for the detection of the Middle-East respiratory syndrome coronavirus (MERS-CoV) is described. Taking advantage of the absorption capability of cotton, the nasal and saliva samples can be collected and directly transferred to the immunosensor surface for detection using a single tool. The immunosensor was fabricated on a disposable screen-printed electrode precoated with carbon nanofibers. The electrodes were functionalized with carboxyphenyl groups that were used for the immobilization of the spike protein of the MERS-CoV. A competitive detection scheme was employed using the antibody for the MERS-CoV spike protein, and the square-wave voltammetry technique was used for measurements. The biosensor tested after the cotton coating of the electrode exhibited excellent performance. The biosensor was capable of detecting the MERS-CoV spike protein within a concentration range from 0.1 pg·mL to 1 μg·mL with a limit of detection of 0.07 pg·mL, implying the high sensitivity of the method. The immunosensor did not exhibit any cross-reactivity against proteins from HCoV and Influenza A, indicating the excellent selectivity of this approach. Testing of the biosensor in nasal samples showed very high recovery percentages. This disposable biosensor can be used as a miniaturized device for the collection of samples and detection of the virus using a portable potentiostat connected to a smartphone.
用于即时诊断的生物传感器小型化在感染控制中非常重要。电化学生物传感器在诊断方面具有成本、一次性使用、便携性和灵敏度等诸多优势。本文描述了一种结合棉纤维用于检测中东呼吸综合征冠状病毒（MERS-CoV）的小型化电化学免疫传感器。利用棉的吸附能力，可使用单一工具收集鼻和唾液样本并直接转移至免疫传感器表面进行检测。该免疫传感器制作在预涂有碳纳米纤维的一次性丝网印刷电极上。电极用羧苯基官能化，用于固定MERS-CoV的刺突蛋白。采用针对MERS-CoV刺突蛋白的抗体的竞争检测方案，并使用方波伏安法进行测量。电极进行棉涂层后测试的生物传感器表现出优异性能。该生物传感器能够在0.1 pg·mL至1 μg·mL的浓度范围内检测MERS-CoV刺突蛋白，检测限为0.07 pg·mL，表明该方法具有高灵敏度。该免疫传感器对人冠状病毒（HCoV）和甲型流感病毒的蛋白未表现出任何交叉反应，表明该方法具有优异的选择性。在鼻样本中对该生物传感器进行测试显示回收率非常高。这种一次性生物传感器可用作一种小型化设备，通过连接到智能手机的便携式恒电位仪收集样本并检测病毒。
