基于铂黑的微针电极阵列表面修饰方法

Surface Modification Method of Micro-Needle Electrode Array Based on Platinum Black

由于微针电极阵列尖端直径小,空间分辨率高,可以记录单个神经元的放电活动,已成为神经信号记录的首选。但商用微针电极阵列的阻抗较高,降低电极阻抗有利于提高信噪比,改善记录信号质量。采用超声电镀铂黑的方法对微针电极表面进行修饰。测试结果表明铂黑修饰后的微针电极电化学性能优异,1 kHz处阻抗约为2.5 kΩ,相比裸金电极降低了两个数量级,电荷存储量增加到2.988×10-6 C。此外,机械超声测试和循环伏安扫描测试证明了电极具有良好的机械和电化学稳定性。这使铂黑修饰的微针电极阵列有望在体内植入研究中实现电极所需的高灵敏度及高空间分辨率。

The micro-needle electrode array with small tip diameter and high spatial resolution endows the merits of recording the spiking activity of the single neuron and has become the first choice to record the neural signal.However,the commercially available micro-needle electrode array has high impedance,and lowering the electrode impedance can increase the signal-to-noise ratio and improve the quality of the recording signal.A method of ultrasonic electroplating platinum black was used to modify the surface of micro-needle electrodes.The test results show that the micro-needle electrodes modified by platinum black are of excellent electrochemical performance.The impedance of the micro-needle electrode is about 2.5 kΩat 1 kHz,which is reduced by two orders of magnitude compared with that of the bare gold electrode,and the charge storage capacity is increased to 2.988×10-6 C.In addition,the test results of mechanical ultrasonic and cycle voltammetry scanning demonstrate that the electrodes have good mechanical and electrochemical stability.Therefore the micro-needle electrode array modified by platinum black is expected to achieve high sensitivity and high spatial resolution required in vivo implantation research.