Novel methods for selecting signaling aptamers

生物传感器依赖于生物分子，如蛋白质和脱氧核糖核酸（DNA）进行检测。众所周知的例子包括血糖仪和怀孕测试试剂盒。前者彻底改变了糖尿病患者的医疗保健;后者是目前诊断妊娠的金标准。如果更多的疾病或症状，如癌症和心脏病发作，可以很容易地诊断，更多的人将受益于生物传感器。同样重要的是检测环境污染物。DNA作为遗传物质的功能已经知道很久了。近年来，人们发现单链DNA的某些序列可以特异性地结合许多分子，这些结合DNA被称为DNA适体。与抗体相比，DNA适体具有相似甚至更好的结合性能、更高的稳定性和更低的成本。因此，核酸适体作为一种新型的生物传感器设计试剂正在兴起。通过选择程序获得适体。从一个包含数百万亿随机DNA的巨大文库开始，只选择和扩增可以结合靶分子的序列。尽管该方法已成功应用于适体选择，但其具有几个主要缺点，包括需要将靶分子连接到柱和多轮（通常>10轮）选择。目前，只有少数高质量的小分子DNA适体可用。为了解决这些问题，我建议开发新的适配体选择方法，通过DNA文库固定。最初的选择目标包括与疾病相关的激素、营养素和环境污染物。一批高素质的人才，包括研究生和本科生将与本研究计划进行培训。他们将接触到一个高度跨学科和多学科的研究环境，学习各种分子生物学和分析化学技术，并开发新的纳米技术为基础的方法。预计拟议的研究将有利于加拿大的医疗保健，环境和经济。

Biosensors rely on biomolecules such as proteins and deoxyribonucleic acids (DNAs) for detection. Well-known examples include glucose meters and pregnancy test kits. The former has revolutionized the health care of diabetic patients; and the latter is the current gold standard for diagnosis of pregnancy. Many more people will benefit from biosensors if more diseases or symptoms, such as cancer and heart attack, can be easily diagnosed. Of equal importance is the detection of environmental contaminants. DNA has been known for its function as a genetic material for a long time. Recently, it was discovered that certain sequences of single-stranded DNAs can specifically bind many molecules and these binding DNAs are called DNA aptamers. Compared to antibodies, DNA aptamers have similar or even better binding performance, higher stability and lower cost. Therefore, aptamers are emerging as a new class of reagent for biosensor design. Aptamers are obtained through a selection procedure. Starting with a huge library containing hundreds of trillions of random DNAs, only sequences that can bind target molecules are selected and amplified. Although this method has been successfully applied for aptamer selection, it has several main drawbacks including the needs of linking target molecules to a column and multiple rounds (generally >10) of selection. Currently, only a few high-quality DNA aptamers for small molecules are available. To address these problems, I propose to develop novel aptamer selection methods through DNA library immobilization. Initial targets for selection include disease related hormones, nutrients, and environmental contaminants. A number of highly qualified personnel including graduate and undergraduate students will be trained with this research program. They will be exposed to a highly inter- and multi-disciplinary research environment, learn various molecular biology and analytical chemistry techniques, and develop new nanotechnology-based methods. It is expected that the proposed research will benefit Canada's health care, the environment, and economy.