Nano-materials and Chemistry Key Laboratory, Wenzhou University, Wenzhou, Zhejiang, 325027, China.
Biosens Bioelectron. 2012 Mar 15;33(1):279-83. doi: 10.1016/j.bios.2011.12.039. Epub 2011 Dec 27.
A new platform based on electrochemical growth of Au nanoparticles on horizontally aligned single walled carbon nanotube (SWCNT) array was developed for ultrasensitive DNA detection. The as-prepared DNA-functionalized SWCNT-Au platform, in which every gold-coated SWCNT acts as an isolated micro electrode, could detect lower than 10 zmol complimentary 10-base DNA, which corresponded to having 6 DNA molecules in a 1 mL sample solution. For a 1-base mismatched DNA, the experimental detection limit was 100 amol. A linear relationship between the change of charge transfer resistance and target DNA concentration was achieved at low concentration range. Over the extended DNA concentration range, the change of charge transfer resistance was found to have a linear relationship with respect to the logarithm of the target DNA concentration. The sensor also showed great stability and could be conveniently regenerated via dehybridization in hot water. The significant improvement in sensitivity illustrates that combining Au nanoparticles with the on-site fabricated SWCNT array represents a promising platform for achieving ultrasensitive biosensor.
一种新的基于电化学生长金纳米粒子在水平排列的单壁碳纳米管（SWCNT）阵列上的平台被开发用于超灵敏的 DNA 检测。所制备的 DNA 功能化的 SWCNT-Au 平台，其中每个镀金的 SWCNT 作为一个独立的微电极，可以检测低于 10 zmol 的互补 10 碱基 DNA，这相当于在 1 毫升样品溶液中有 6 个 DNA 分子。对于 1 个碱基错配的 DNA，实验检测限为 100 amol。在低浓度范围内，电荷转移电阻的变化与目标 DNA 浓度之间呈现线性关系。在扩展的 DNA 浓度范围内，电荷转移电阻的变化与目标 DNA 浓度的对数呈线性关系。该传感器还表现出很好的稳定性，并且可以通过在热水中解杂交方便地再生。灵敏度的显著提高表明，将金纳米粒子与现场制备的 SWCNT 阵列相结合代表了实现超灵敏生物传感器的一个很有前途的平台。
