Institute of Advanced Technology, Universiti Putra Malaysia, 43400, Serdang, Selangor, Malaysia.
Department of Chemistry, Faculty of Science, Universiti Putra Malaysia, 43400, Serdang, Selangor, Malaysia.
Mikrochim Acta. 2021 Jan 6;188(1):20. doi: 10.1007/s00604-020-04669-x.
An early detection of Mycobacterium tuberculosis is very important to reduce the number of fatal cases and allow for fast recovery. However, the interpretation of the result from smear microscopy requires skilled personnel due to the propensity of the method to produce false-negative results. In this work, a portable, rapid, and simple sandwich-type immunosensor reader has been developed that is able to detect the presence of M. tuberculosis in sputum samples. By using sandwich-type immunosensor, an anti-CFP10-ESAT6 antibody was immobilized onto the graphene/polyaniline (GP/PANI)-modified gold screen-printed electrode. After incubation with the target CFP10-ESAT6 antigen, the iron/gold magnetic nanoparticles (FeO/Au MNPs) conjugated with anti-CFP10-ESAT6 antibody were used to complete the sandwich format. Differential pulse voltammetry (DPV) technique was used to detect the CFP10-ESAT6 antigen at the potential range of 0.0-1.0 V. The detection time is less than 2 h. Under optimal condition, CFP10-ESAT6 antigen was detected in a linear range from 10 to 500 ng mL with a limit of detection at 1.5 ng mL. The method developed from this process was then integrated into a portable reader. The performance of the sensor was investigated and compared with the standard methods (culture and smear microscopy). It provides a good correlation (100% sensitivity and 91.7% specificity) with both methods of detection for M. tuberculosis in sputum samples henceforth, demonstrating the potential of the device as a more practical screening tool.Graphical abstract.
早期发现结核分枝杆菌对于减少死亡病例数量和促进快速康复非常重要。然而，由于该方法容易产生假阴性结果，因此对涂片显微镜检查结果的解释需要专业人员。在这项工作中，开发了一种便携式、快速且简单的三明治型免疫传感器读取器，能够检测痰液样本中结核分枝杆菌的存在。通过使用三明治型免疫传感器，将抗 CFPl0-ESAT6 抗体固定在石墨烯/聚苯胺 (GP/PANI)-修饰的金丝网印刷电极上。与靶标 CFPl0-ESAT6 抗原孵育后，用与抗 CFPl0-ESAT6 抗体偶联的铁/金磁纳米粒子 (FeO/Au MNPs) 完成三明治结构。差分脉冲伏安法 (DPV) 技术用于在 0.0-1.0 V 的电位范围内检测 CFPl0-ESAT6 抗原。检测时间少于 2 小时。在最佳条件下，CFPl0-ESAT6 抗原在 10 至 500 ng mL 的线性范围内被检测到，检测限为 1.5 ng mL。从该过程开发的方法随后被集成到便携式读取器中。对传感器的性能进行了研究，并与标准方法（培养和涂片显微镜检查）进行了比较。它与两种检测方法在痰液样本中对结核分枝杆菌的检测具有良好的相关性（100%的敏感性和 91.7%的特异性），从而证明了该设备作为更实用的筛选工具的潜力。
