Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, 21 Nanyang Link, Nanyang Technological University, Singapore 637171, Singapore.
Biosens Bioelectron. 2012 Feb 15;32(1):133-40. doi: 10.1016/j.bios.2011.11.046. Epub 2011 Dec 7.
An electrochemically amplified molecular beacon (EAMB) biosensor is constructed using thiolated hairpin DNA-ferrocene probes on gold electrode. The switching from "on" to "off" states of individual probes in the presence of complementary DNA target influences the electrode potential, besides the current, owing to changes in surface density of the electroactive hairpin DNA-ferrocene probes. The EAMB biosensor demonstrates linear range over 8 orders of magnitude with ultrasensitive detection limit of 2.3 × 10(-14)M for the quantification of a 21-mer DNA sequence. Its applicability is tested against PCR amplicons derived from genomic DNA of live Legionella pneumophila. Excellent specificity down to one and three nucleotides mismatches in another strain of L. pneumophila and a different bacterium species, respectively, is demonstrated.
电化学放大分子信标（EAMB）生物传感器是在金电极上使用巯基化发夹 DNA-二茂铁探针构建的。在互补 DNA 靶存在的情况下，单个探针从“开”到“关”状态的切换除了电流外，还会影响电极电势，这是由于电活性发夹 DNA-二茂铁探针的表面密度发生了变化。EAMB 生物传感器在 8 个数量级的范围内显示出线性范围，对 21 个碱基 DNA 序列的定量检测具有超灵敏的检测限 2.3×10^(-14)M。它的适用性通过对来自活嗜肺军团菌基因组 DNA 的 PCR 扩增子进行了测试。分别在另一种嗜肺军团菌菌株和一种不同的细菌物种中显示出了极好的特异性，错配一个和三个核苷酸的比例分别为 1%和 3%。
