Department of Physics and Astronomy, Seoul National University, Seoul, 151-742, Korea.
Lab Chip. 2011 Jan 7;11(1):52-6. doi: 10.1039/c0lc00259c. Epub 2010 Oct 22.
A portable sensor platform for the detection of small molecular species is crucial for the on-site monitoring of environmental pollutants, food toxicants, and disease-related metabolites. However, it is still extremely difficult to find highly selective and sensitive sensor platforms for general small molecular detection. Herein, we report aptamer sandwich-based carbon nanotube sensor strategy for small molecular detection, where aptamers were utilized to capture target molecules as well as to enhance the sensor signals. We successfully demonstrated the detection of non-polar bisphenol A molecules with a 1 pM sensitivity. Significantly, our sensors were able to distinguish between similar small molecular species with single-carbon-atomic resolution. Furthermore, using the additional biotin modification on labeling aptamer, we enhanced the detection limit of our sensors down to 10 fM. This strategy allowed us to detect non-polar small molecular species using carbon nanotube transistors, thus overcoming the fundamental limitation of field effect transistor-based sensors. Considering the extensive applications of sandwich assay for the detection of rather large biomolecules, our results should open up completely new dimension in small molecular detection technology and should enable a broad range of applications such as environmental protection and food safety.
用于检测小分子物质的便携式传感器平台对于现场监测环境污染物、食物毒素和与疾病相关的代谢物至关重要。然而，要找到用于一般小分子检测的高选择性和高灵敏度的传感器平台仍然极其困难。在此，我们报告了基于适体夹心的碳纳米管传感器策略用于小分子检测，其中适体既用于捕获目标分子，也用于增强传感器信号。我们成功地以 1 pM 的灵敏度检测到非极性双酚 A 分子。重要的是，我们的传感器能够以单碳原子分辨率区分相似的小分子物质。此外，通过在标记适体上添加额外的生物素修饰，我们将传感器的检测限提高到 10 fM。该策略允许我们使用碳纳米管晶体管检测非极性小分子物质，从而克服了基于场效应晶体管传感器的基本限制。考虑到夹心测定法在检测较大生物分子方面的广泛应用，我们的结果应该在小分子检测技术方面开辟全新的维度，并能够实现广泛的应用，如环境保护和食品安全。
