纳米金-碳管敏感膜对溶血素的快速电信号检测

Fast Electrical Signal Detection for Listeriolysin by Sensitive Membrane of Nanogold-modified Carbon Nanotubes

在O2等离子体处理和空气气氛中500℃高温热处理方法的辅助下,简便制备了单壁碳管-纳米金(SWNT-Au)复合网络敏感膜。等离子体处理的SWNTs高密度且均一地组装了正电荷Au纳米颗粒。热处理过程不仅去除了SWNTs表面吸附的所有杂质,使其与叉指金电极形成良好的接触;而且导致Au颗粒表面熔化并聚集,残余的SWNTs管束变细。这些变化极大地改变了敏感膜作为换能器的电流-电压行为,放大了其对抗体-抗原相互作用事件的敏感性。利用敏感膜作为换能元件,构建了基于SWNT-Au网络的电信号生物免疫传感器,实现了对李斯特氏菌溶血素的高敏感、快速检测,检测限能达到约2ng.mL-1左右。

We proposed a new strategy to facilely hybridize the SWNTs and Au NPs. The SWNT-Au network was used to bridge the interdigital electrode for constructing an immunosensor. Positively-charged Au NPs can be assembled high-density on the oxidized SWNTs. And we carried out the annealing at 500℃ in air for the Au NPs surface melting and aggregation. The impurities adsorbed on the SWNT-Au was removed and a good contact was formed between the SWNT-Au and the electrode. The voltage and current transducer behavior of this sensitive film was greatly changed and further enlarged its sensitivity to antibody-antigen interaction events. As energy conversion devices using sensitive membrane, the electrical signals of biological immune sensor was monitored based on SWNT-Au neural network. A highly sensitive,rapid detection of Listeria hemolysin,was realized and the detection limit can reach about 2 ng · mL.