Lillis Brian, Manning Mary, Hurley Eileen, Berney Helen, Duane Russell, Mathewson Alan, Sheehan Michelle M
Tyndall National Institute, Prospect Row, Cork, Ireland.
Biosens Bioelectron. 2007 Feb 15;22(7):1289-95. doi: 10.1016/j.bios.2006.05.021. Epub 2006 Jun 27.
The analytical performance of an enhanced surface area electrolyte insulator semiconductor (EIS) device was investigated for DNA sensor development. The work endeavored to advance EIS performance by monitoring the effect of DNA probe layers have on the impedimetric signal during target hybridisation detection. Two universally employed covalent chemistries, direct and spacer-mediated attachment of amino modified probe molecules to amino-functionalised surfaces were investigated. Relative areal densities of immobilised probe were measured on planar and enhanced surface area substrates using epi-fluorescence microscopy. The reproducibility of the each immobilisation method was seen to have a direct effect on the reproducibility of the impedimetric signal. The sensitivity and selectivity was seen to be dependent on the type of immobilisation method. Real time, impedimetric detection of target DNA hybridisation concentrations as low as 25 and 1 nM were possible. The impact that probe concentration had on the impedimetric signal for selective and non-selective interactions was also investigated.
为了开发DNA传感器，研究了增强表面积电解质绝缘体半导体（EIS）器件的分析性能。这项工作致力于通过监测DNA探针层在目标杂交检测过程中对阻抗信号的影响来提高EIS性能。研究了两种普遍使用的共价化学方法，即氨基修饰的探针分子直接和通过间隔物介导连接到氨基功能化表面。使用落射荧光显微镜在平面和增强表面积的基板上测量固定探针的相对面密度。可以看出，每种固定方法的重现性对阻抗信号的重现性有直接影响。灵敏度和选择性取决于固定方法的类型。可以实时阻抗检测低至25 nM和1 nM的目标DNA杂交浓度。还研究了探针浓度对选择性和非选择性相互作用的阻抗信号的影响。
