Kim Suphil, Kim Tae Gyun, Byon Hye Ryung, Shin Hyun-Joon, Ban Changill, Choi Hee Cheul
J Phys Chem B. 2009 Sep 10;113(36):12164-8. doi: 10.1021/jp9063559.
Label-free and real-time detections of mismatched dsDNAs are demonstrated using MutS-protein-immobilized, single-walled carbon nanotube field effect transistor (SWNT-FET) devices. The E. coli MutS proteins specifically recognizing mismatched dsDNAs are immobilized on SWNT-FET devices that have been fabricated for high sensitivity using a shadow mask lithographic technique to obtain a thin and wide Schottky contact region. The MutS-immobilized SWNT-FETs have successfully detected 40 base pair dsDNAs having single G-T mismatches at the 20th base pair positions by displaying significant electrical conductance drops at as low as 100 pM concentration. Systematic control experiments have revealed that the signal changes indeed originated from specific recognitions of mismatched DNAs by the immobilized MutS proteins.
利用固定有MutS蛋白的单壁碳纳米管场效应晶体管（SWNT-FET）器件，实现了错配双链DNA的无标记实时检测。将特异性识别错配双链DNA的大肠杆菌MutS蛋白固定在采用荫罩光刻技术制造的具有高灵敏度的SWNT-FET器件上，以获得薄而宽的肖特基接触区域。固定有MutS的SWNT-FET在低至100 pM浓度时通过显示出显著的电导下降，成功检测到在第20个碱基对位置具有单个G-T错配的40碱基对双链DNA。系统的对照实验表明，信号变化确实源于固定的MutS蛋白对错配DNA的特异性识别。
