Lin Chia-Hung, Lin Ming-Jie, Wu Ching-Chou
Department of Bio-industrial Mechatronics Engineering, National Chung Hsing University.
Anal Sci. 2017;33(3):327-333. doi: 10.2116/analsci.33.327.
An ultrasensitive label-free impedimetric immunosensor is constructed by modifying a 3-mercaptoproponic acid (MPA) monolayer on highly rough gold nanostructure (AuNS)-electrodeposited screen printed carbon electrodes (SPCEs) for the detection of small molecular weight drugs (SMWDs), such as salbutamol (SAL). The SPCEs preoxidized in a 0.1 M HSO solution (called po-SPCE) are electrodeposited with the AuNS to increase the roughness factor to 23.64 ± 1.76, larger than the AuNS/po-SPCE or the AuNS/po-SPCE. Furthermore, the MPA modified layer as a link for the anti-SAL immobilization to give the immunosensors an impedimetric signal-to-noise ratio larger than the 11-mercapto-undecanoic acid- and 16-mercaptohexadecanoic acid-modified layer, due to the lower interfacial impedance of the MPA monolayer. The MPA/AuNS/po-SPCE-based immunosensors have a wide linear range of 1 fg mL to 1 ng mL and a limit of detection of 0.6 fg mL. Moreover, the immunosensors can practically quantify the SAL concentrations in 1000 times-diluted serum samples with good recovery.
通过在高度粗糙的金纳米结构（AuNS）电沉积丝网印刷碳电极（SPCE）上修饰3-巯基丙酸（MPA）单层，构建了一种超灵敏的无标记阻抗免疫传感器，用于检测小分子重量药物（SMWD），如沙丁胺醇（SAL）。在0.1 M HSO溶液中预氧化的SPCE（称为po-SPCE）与AuNS进行电沉积，使粗糙度因子增加到23.64±1.76，大于AuNS/po-SPCE或AuNS/po-SPCE。此外，MPA修饰层作为抗SAL固定的连接层，由于MPA单层的界面阻抗较低，使得免疫传感器的阻抗信噪比大于11-巯基十一烷酸和16-巯基十六烷酸修饰层。基于MPA/AuNS/po-SPCE的免疫传感器具有1 fg mL至1 ng mL的宽线性范围和0.6 fg mL的检测限。此外，该免疫传感器能够实际定量1000倍稀释血清样品中的SAL浓度，回收率良好。
