In recent years, need for rapid, reliable, and low-cost protein biomarker screening has tremendously boosted research into the development of electrochemical immunosensors. In this line, here we report on rapid fabrication and proof-of-concept demonstration of a hyper-branched gold nanostructure (ns@gold) based electrochemical immunosensor for detection of protein biomarker at pg/mL level. We have optimized a simple direct electrochemical process to rapidly generate uniformly distributed high surface area ns@gold within 30 min. These 3D ns@gold show ∼ 8-times enhancement in conductivity and also a rapid surface functionalization via self-assembled monolayers (SAM) of mercaptoundecanoic acid within 45 min. Protein estimation data showed around 94 % immobilization efficiency on the ns@gold surface in comparison to 28.4 % on plain gold surface. A fast SAM formation and quick antibody immobilization steered the assay timing within 4 h. As a proof-of-concept, we used an antibody-antigen interaction for the detection of epithelial growth factor receptor (EGFR) protein. Voltammetric data for the target EGFR receptor resulted a linear working range of 10 pg/mL to 100 ng/mL with a low limit-of-detection of 6.9 pg/mL. High selectivity in detecting target proteins from a pool of non-target proteins using breast cancer cell lines was also demonstrated along with good stability and reusability.

近年来，对快速，可靠，低成本的蛋白质生物标志物筛选的需求极大地促进了电化学免疫传感器开发的研究。在这条线中，我们在此报告基于pg / mL水平的蛋白质生物标志物检测的基于超支化金纳米结构（ns @ gold）的电化学免疫传感器的快速制备和概念验证。我们优化了一个简单的直接电化学过程，以在30分钟内快速生成均匀分布的高表面积ns @ gold。这些3D ns @ gold在45分钟内通过巯基癸酸的自组装单分子层（SAM）表现出了约8倍的电导率增强和快速的表面功能化。蛋白质估计数据显示，在ns @ gold表面的固定效率约为94％，而在纯金表面的固定率为28.4％。快速的SAM形成和快速的抗体固定可在4小时内控制测定时间。作为概念验证，我们使用了抗体-抗原相互作用来检测上皮生长因子受体（EGFR）蛋白。目标EGFR受体的伏安数据导致线性工作范围为10 pg / mL至100 ng / mL，检测下限为6.9 pg / mL。还证明了使用乳腺癌细胞系从非靶蛋白库中检测靶蛋白的高选择性以及良好的稳定性和可重复使用性。目标EGFR受体的伏安数据导致线性工作范围为10 pg / mL至100 ng / mL，检测下限为6.9 pg / mL。还证明了使用乳腺癌细胞系从非靶蛋白库中检测靶蛋白的高选择性以及良好的稳定性和可重复使用性。目标EGFR受体的伏安数据导致线性工作范围为10 pg / mL至100 ng / mL，检测下限为6.9 pg / mL。还证明了使用乳腺癌细胞系从非靶蛋白库中检测靶蛋白的高选择性以及良好的稳定性和可重复使用性。