We report on the fabrication of a microneedle‐based electrochemical biosensor for use in transdermal biosensing, which includes a screen‐printed electrode containing a Prussian blue‐gold nanohybrid as the working electrode. The Prussian blue gold nanohybrid is made from polyethylenime (PEI)‐ mediated simultaneous synthesis of Prussian blue (PBNP) and gold nanoparticles (AuNP), which forms a PBNP‐AuNP nanohybrid with a remarkable change in the Prussian blue character. PEI‐protected polycrystalline PBNPs can be synthesized in acidic media from the single precursor potassium ferricyanide [K₃Fe(CN)₆] at 60°C. Since PEI also enables the controlled formation of gold nanoparticles (AuNPs) in the presence of formaldehyde, nanohybrids containing PBNPs and AuNPs may be prepared. Two different methods of PEI mediated synthesis of AuNP in the presence of PBNP were considered. In Method 1, AuNP and PBNP were made independently and mixed together in an appropriate ratio. In Method 2, PBNPs were made first, followed by PEI‐ and formaldehyde‐mediated reduction of gold cations in the presence of PBNP. PBNP‐AuNPs display a remarkable change in Prussian blue behavior such that the absorption maxima of PBNP‐AuNPs made through Method 1 tend to increase at 670 nm as a function of gold concentration as compared with the control; the reverse was observed when PBNP‐AuNPs were made through Method 2. As made PBNPs and PBNP‐AuNPs made through Method 1 display excellent catalytic activity toward both reduction and oxidation of hydrogen peroxide based on peroxidase mimetic activity. In addition, the as‐synthesized PBNPs displayed superparamagnetic behavior that can be manipulated in the presence of AuNPs. The results from peroxidase mimetic activity, chemiluminescence, cyclic voltammetry, and amperometry showed suitable analytical performance of the as‐made PBNP‐AuNP nanohybrid for biomedical applications.

中文翻译：

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基于普鲁士蓝金纳米杂化修饰丝网印刷电极的微针透皮电化学生物传感器。

我们报告了用于透皮生物传感的基于微针的电化学生物传感器的制造，其中包括一个丝网印刷电极，该电极含有普鲁士蓝金纳米杂化物作为工作电极。普鲁士蓝金纳米杂化物由聚乙烯（PEI）介导的普鲁士蓝（PBNP）和金纳米粒子（AuNP）同时合成，形成了普鲁士蓝特性发生显着变化的 PBNP-AuNP 纳米杂化物。PEI 保护的多晶 PBNPs 可以在酸性介质中由单一前体铁氰化钾 [K ₃ Fe(CN) ₆] 在 60°C。由于 PEI 还能够在甲醛存在下控制金纳米粒子 (AuNPs) 的形成，因此可以制备含有 PBNPs 和 AuNPs 的纳米混合物。考虑了在 PBNP 存在下 PEI 介导的 AuNP 合成的两种不同方法。在方法 1 中，AuNP 和 PBNP 分别制备并以适当的比例混合在一起。在方法 2 中，首先制备 PBNP，然后在 PBNP 存在下通过 PEI 和甲醛介导的金阳离子还原。PBNP-AuNPs 表现出普鲁士蓝行为的显着变化，因此与对照相比，通过方法 1 制备的 PBNP-AuNPs 的吸收最大值在 670 nm 处趋于增加，作为金浓度的函数；当通过方法 2 制备 PBNP-AuNPs 时，观察到相反的情况。通过方法 1 制备的 PBNPs 和 PBNP-AuNPs 对基于过氧化物酶模拟活性的过氧化氢的还原和氧化表现出优异的催化活性。此外，合成的 PBNPs 表现出超顺磁性，可以在 AuNPs 存在的情况下进行操作。过氧化物酶模拟活性、化学发光、循环伏安法和电流分析法的结果表明，所制备的 PBNP-AuNP 纳米杂化物具有适合生物医学应用的分析性能。