Biosensors and Bioelectronics ( IF 12.6 ) Pub Date : 2018-05-10 , DOI: 10.1016/j.bios.2018.05.016 Xin Zhang , Ning Bao , Xiliang Luo , Shou-Nian Ding
In this work, novel multifunctional patchy gold coated Fe3O4 hybrid nanoparticles (PG-Fe3O4 NPs) have been successfully synthesized in aqueous medium via a facile adsorption-reduction method. A rational formation mechanism has been proposed by monitoring the morphological evolution. The PG-Fe3O4 NPs retained the good magnetic property and exhibited excellent catalytical effeciency towards the electrochemical reduction of hydrogen peroxide. Chronoamperometric and amperometric experiments indicated a relatively high catalytic rate constant of 3.13 × 105 M−1 s−1, a high sensitivity of 578.87 µA mM−1 cm−2 and a low Michaelis-Menten constant of 462 µM. Meanwhile, the introduction of patchy gold could help biofunctionalization via Au-S bond for different biodetection and biosensing purposes. Here, as an example, thiol-terminated aptamers were immobilized onto the patchy gold part as a signal probe to detect carcinoembryonic antigen (CEA). A related paper-based bipolar electrode-electrochemiluminescence (pBPE-ECL) aptasensor was fabricated as the low-cost, disposable and miniature platform. To improve the sensitivity, Au nanodendrites were electrodeposited at the BPE cathode as the matrix for Apt1 immobilization. This aptasensor showed a wide linear range of 0.1 pg mL−1–15 ng mL−1 with a low detection limit of 0.03 pg mL−1, remaining competitive against other ones, and also demonstrating the PG-Fe3O4 NPs have promising potential for catalysis and bioassays.
中文翻译:
应用于催化纸基双极电极-电化学发光适体的具有增强催化活性的修补金涂覆的Fe 3 O 4纳米球
在这项工作中,已经通过一种简便的吸附还原方法成功地在水性介质中合成了新型多功能的斑片状包金的Fe 3 O 4杂化纳米颗粒(PG-Fe 3 O 4 NPs)。通过监测形态演化提出了一种合理的形成机理。PG-Fe 3 O 4 NP保留了良好的磁性,并且对过氧化氢的电化学还原表现出优异的催化效率。计时安培和安培实验表明,相对较高的催化速率常数为3.13×10 5 M -1 s -1,高灵敏度为578.87 µA mM-1 cm -2和低的Michaelis-Menten常数462 µM。同时,斑金的引入可以帮助通过Au-S键实现生物功能化,从而实现不同的生物检测和生物传感目的。在此,例如,将巯基封端的适体作为信号探针固定在斑驳的金部分上,以检测癌胚抗原(CEA)。相关的纸基双极电极电化学发光(pBPE-ECL)适体传感器被制造为低成本,一次性使用的微型平台。为了提高灵敏度,在BPE阴极上电沉积Au纳米树枝晶,作为固定Apt1的基质。该适体传感器的线性范围很广,为0.1 pg mL -1 –15 ng mL -1,检测限很低,为0.03 pg mL -1,保持与其他产品的竞争优势,并且证明PG-Fe 3 O 4 NP在催化和生物测定方面具有广阔的前景。