Wang Xu, Ozkan Cengiz S
Department of Chemical and Environmental Engineering, University of California, Riverside, California 92521, USA.
Nano Lett. 2008 Feb;8(2):398-404. doi: 10.1021/nl071180e. Epub 2008 Jan 23.
We describe a novel application for detecting specific single strand DNA sequences using multisegment nanowires via a straightforward surface functionalization method. Nanowires comprising CdTe-Au-CdTe segments are fabricated using electrochemical deposition, and electrical characterization indicates a p-type behavior for the multisegment nanostructures, in a back-to-back Schottky diode configuration. Such nanostructures modified with thiol-terminated probe DNA fragments could function as high fidelity sensors for biomolecules at very low concentration. The gold segment is utilized for functionalization and binding of single strand DNA (ssDNA) fragments while the CdTe segments at both ends serve to modulate the equilibrium Fermi level of the heterojunction device upon hybridization of the complementary DNA fragments (cDNA) to the ssDNA over the Au segment. Employing such multisegment nanowires could lead to the fabrication more sophisticated and high multispecificity biosensors via selective functionalization of individual segments for biowarfare sensing and medical diagnostics applications.
我们描述了一种通过直接的表面功能化方法，利用多段纳米线检测特定单链DNA序列的新应用。采用电化学沉积法制备了包含CdTe-Au-CdTe段的纳米线，电学表征表明，在背靠背肖特基二极管配置下，多段纳米结构呈现p型行为。用硫醇封端的探针DNA片段修饰的此类纳米结构可作为极低浓度生物分子的高保真传感器。金段用于单链DNA（ssDNA）片段的功能化和结合，而两端的CdTe段则用于在互补DNA片段（cDNA）与金段上的ssDNA杂交时调节异质结器件的平衡费米能级。通过对各个段进行选择性功能化，以用于生物战传感和医学诊断应用，采用这种多段纳米线可制造出更复杂、多特异性更高的生物传感器。
