School of Pharmacy, Lanzhou University, Lanzhou 730000, China.
Center for Inflammation, Translational and Clinical Lung Research, Temple University School of Medicine, Philadelphia, PA, USA.
Mater Sci Eng C Mater Biol Appl. 2020 Jun;111:110797. doi: 10.1016/j.msec.2020.110797. Epub 2020 Mar 2.
As a new type of conductive material, polyaniline functionalized graphene quantum dots (PAGD), which were prepared by in-situ polymerization had been used to construct a novel electrochemical immunosensor for early screening of depression markers-heat shock protein 70 (HSP70). Profiting from the huge specific surface area, good bioactivity and excellent structure of PAGD, a variety of heat shock protein 70 (HSP70) was firmly loaded on the surface of PAGD for successful construction of basic electrode (HSP70/PAGD/GCE), which was characterized by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS), respectively. Due to the HSP70 fixed on the surface of basic electrode and the HSP70 in the samples can competitively combine with the horseradish peroxidase labeled human HSP70 antibody (HRP-Strept-Biotin-Ab). As a result, there is negative correlation between the concentration of HSP70 in samples and the detection signal of the proposed electrochemical immunosensor (HRP-Strept-Biotin-Ab-HSP70/PAGD/GCE) in the test liquid. Under conditions optimized for determining HSP70, wide linearity was obtained in the range of 0.0976-100 ng/mL, with a low detection limit of 0.05 ng/mL at 3σ. Moreover, the proposed electrochemical immunosensors was successfully applied to detect HSP70 in plasma samples, and exhibited good precision, acceptable stability and reproducibility. Therefore, this study provides a novel and convenient method for early clinical screening of depression markers, and also provides a reliable and objective analysis method for the diagnosis of depression at the molecular level.
作为一种新型的导电材料，通过原位聚合制备的聚苯胺功能化石墨烯量子点（PAGD）已被用于构建一种新型电化学免疫传感器，用于早期筛选抑郁症标志物-热休克蛋白 70（HSP70）。由于 PAGD 具有巨大的比表面积、良好的生物活性和优异的结构，大量的热休克蛋白 70（HSP70）被牢固地负载在 PAGD 表面上，成功构建了基本电极（HSP70/PAGD/GCE），分别通过循环伏安法（CV）和电化学阻抗谱（EIS）进行了表征。由于固定在基本电极表面上的 HSP70 以及样品中的 HSP70 可以与辣根过氧化物酶标记的人 HSP70 抗体（HRP-Strept-Biotin-Ab）竞争结合，因此，样品中 HSP70 的浓度与所提出的电化学免疫传感器（HRP-Strept-Biotin-Ab-HSP70/PAGD/GCE）的检测信号呈负相关。在优化的 HSP70 测定条件下，在 0.0976-100 ng/mL 的范围内获得了宽的线性范围，检测限低至 0.05 ng/mL（3σ）。此外，该电化学免疫传感器成功地应用于检测血浆样品中的 HSP70，表现出良好的精密度、可接受的稳定性和重现性。因此，本研究为抑郁症标志物的早期临床筛选提供了一种新颖、方便的方法，也为抑郁症的分子水平诊断提供了一种可靠、客观的分析方法。
