Transparent Electrode Materials for Simultaneous Amperometric Detection of Exocytosis and Fluorescence Microscopy

• 作者: Brian N. Kim Cherian J. Mathai Kassandra Kisler Kevin D. Gillis Khajak Berberian Manfred Lindau Qinghua Fang Shubhra Gangopadhyay Xin Liu
• 来源期刊: 生物材料与纳米技术(英文)
• 学科: 医学
• 关键词: EXOCYTOSIS AMPEROMETRY Fluorescence MICROSCOPY TIRF MICROELECTRODE TRANSPARENT Electrode
• 年，卷（期）: 2012,（2）
• 页码范围: 243-253
• 页数: 11页
• 分类号: R73

摘要

We have developed and tested transparent microelectrode arrays capable of simultaneous amperometric measurement of oxidizable molecules and fluorescence imaging through the electrodes. Surface patterned microelectrodes were fabricated from three different conducting materials: Indium-tin-oxide (ITO), nitrogen-doped diamond-like carbon (DLC) deposited on top of ITO, or very thin (12 - 17 nm) gold films on glass substrates. Chromaffin cells loaded with lysotracker green or acridine orange dye were placed atop the electrodes and vesicle fluorescence imaged with total internal reflection fluorescence (TIRF) microscopy while catecholamine release from single vesicles was measured as amperometric spikes with the surface patterned electrodes. Electrodes fabricated from all three materials were capable of detecting amperometric signals with high resolution. Unexpectedly, amperometric spikes recorded with ITO electrodes had only about half the amplitude and about half as much charge as those detected with DLC or gold electrodes, indicating that the ITO electrodes are not as sensitive as gold or DLC electrodes for measurement of quantal catecholamine release. The lower sensitivity of ITO electrodes was confirmed by chronoamperometry measurements comparing the currents in the presence of different analytes with the different electrode materials.