The Department of Laboratory Medicine , The First Affiliated Hospital of Xiamen University , No. 55 Zhenhai Road , Siming District, Xiamen , Fujian 361005 , China.
School of Chemistry and Chemical Engineering, Key Laboratory of Organo-Pharmaceutical Chemistry of Jiangxi Province , Gannan Normal University , Ganzhou 341000 , P. R. China.
ACS Sens. 2019 Sep 27;4(9):2375-2380. doi: 10.1021/acssensors.9b00968. Epub 2019 Aug 20.
Thermometers, one of the most commonly used instruments at home, are normally adapted to measure temperature directly with high accuracy but rarely adopted to act as readout in the biosensors. It is necessary to find some ways to establish a relationship between the concentration of the target and the temperature change. In this study, a common thermometer was used as readout to develop a convenient immunosensor. The designed immunosensor comprises three components, including target recognition area, water flow system, and exothermic reaction bottle. The capture antibody for the target [carcinoembryonic antigen (CEA) was selected as a model target] was preloaded on the bottom of the recognition area. In the presence of CEA, a sandwich-type structure was formed between the capture antibody, CEA, and biotinylated detection antibody. Then, the streptavidin-functionalized platinum nanoparticles were labeled on the detection antibody due to biotin-avidin interaction. The captured platinum nanoparticles can effectively catalyze the decomposition of HO into O. The continuous production of gas resulted in pressure increment inside the reaction bottle and further pushed the water flow into the exothermic reaction bottle. Finally, the water reacted with calcium oxide to generate a large amount of heat in the exothermic reaction bottle; thereby the temperature inside the bottle was enhanced and recorded by a common thermometer easily. The temperature enhancement has a linear relationship with the CEA concentration in the range of 7.81-500 pg/mL with a detection limit of 0.6 pg/mL. Furthermore, by taking advantage of simplicity, compatibility, stability, and high sensitivity, our temperature-based immunoassay has been applied to detect CEA in human serum samples with satisfactory results.
温度计是家庭中最常用的仪器之一，通常用于直接高精度测量温度，但很少用于生物传感器中的读数。因此，有必要找到一些方法来建立目标浓度与温度变化之间的关系。在这项研究中，我们使用常见的温度计作为读数来开发一种便捷的免疫传感器。该设计的免疫传感器由三个部分组成，包括目标识别区域、水流系统和放热反应瓶。目标[癌胚抗原 (CEA)]的捕获抗体被预先加载到识别区域的底部。在存在 CEA 的情况下，捕获抗体、CEA 和生物素化检测抗体之间形成三明治结构。然后，由于生物素-亲和素相互作用，将链霉亲和素功能化的铂纳米粒子标记在检测抗体上。捕获的铂纳米粒子可以有效地催化 HO 的分解为 O。气体的连续产生导致反应瓶内压力增加，并进一步将水流推入放热反应瓶。最后，水与氧化钙反应在放热反应瓶中产生大量热量，从而提高瓶内温度，并通过普通温度计轻松记录。温度升高与 CEA 浓度在 7.81-500 pg/mL 范围内呈线性关系，检测限为 0.6 pg/mL。此外，我们的基于温度的免疫分析利用了简单、兼容、稳定和高灵敏度的特点，已成功应用于检测人血清样本中的 CEA，结果令人满意。
