Electrodeposited metallic nanostructures with tree-like hierarchical morphology, often termed metallic nanodendrites (MNDs), are gradually gaining interest in the development of electrochemical biosensors. Noble metal nanodendrites exhibit exceptional conductive and electrocatalytic activity. In this work, we have reported a robust method of electrodeposition of gold nanodendrites (AuND). In order to achieve this, we first optimized the number of gold nanoparticles (AuNP) as seed molecules on the sensor surface and observed that “less seed” resulted in enhanced growth of AuND. Thereafter, AuNP/AuND was used as an excellent surface in conjugation with reduced graphene oxide (rGO), chitosan (CS), and an Anti-CEA antibody for electrochemical detection of carcinoembryonic antigen (CEA), a clinically established cancer biomarker. The developed immunosensor, glassy carbon electrode/gold nanoparticle/gold nanodendrites/chitosan-reduced graphene oxide/Anti-CEA antibody (GCE/AuNP/AuND/CS-rGO/Anti-CEA), is capable of detecting the biomarker in the linear dynamic range (LDR) of 1 × 10 to 1 × 10 g/mL, which covers the normal as well as clinical range of CEA in serum with a limit of detection (LOD) of 2.23 (±0.03) x 10 g/mL. Real sample analysis was performed in serum with a recovery rate ranging between 90 and 99.20 %, demonstrating the feasibility of the sensors for CEA monitoring.

中文翻译：

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基于 3D 金树突和还原氧化石墨烯-壳聚糖纳米复合材料的免疫传感器，用于临床环境中的癌胚抗原检测

具有树状分层形态的电沉积金属纳米结构，通常称为金属纳米枝晶（MND），在电化学生物传感器的开发中逐渐引起人们的兴趣。贵金属纳米枝晶表现出优异的导电和电催化活性。在这项工作中，我们报道了一种稳健的金纳米枝晶（AuND）电沉积方法。为了实现这一目标，我们首先优化了传感器表面上作为种子分子的金纳米粒子 (AuNP) 的数量，并观察到“较少的种子”导致 AuND 的生长增强。此后，AuNP/AuND 被用作与还原氧化石墨烯 (rGO)、壳聚糖 (CS) 和抗 CEA 抗体结合的优异表面，用于电化学检测癌胚抗原 (CEA)（一种临床建立的癌症生物标志物）。开发的免疫传感器，玻碳电极/金纳米颗粒/金纳米枝晶/壳聚糖还原氧化石墨烯/抗CEA抗体（GCE/AuNP/AuND/CS-rGO/Anti-CEA），能够以线性动态方式检测生物标志物范围 (LDR) 为 1 × 10 至 1 × 10 g/mL，涵盖了血清中 CEA 的正常范围和临床范围，检测限 (LOD) 为 2.23 (±0.03) x 10 g/mL。在血清中进行真实样品分析，回收率在 90% 至 99.20% 之间，证明了传感器用于 CEA 监测的可行性。