This dissertation describes several novel aptamer engineering and isolation strategies in order to remedy the problem of limited performance of aptamer-based sensors, which arises from the low target affinity and responsiveness of small-molecule binding aptamers.
This dissertation lays out several novel aptamer engineering and isolation strategies aimed at solving the problem of limited performance of aptamer-based sensors, which arises from the low target affinity and responsiveness of small-molecule binding aptamers. The author seeks to relay generalizable strategies that can be used to develop aptamer-based assays for almost any small-molecule targets, by demonstrating the potential of novel aptamer engineering and isolation strategies in generating functional signal-reporting aptamers for sensitive small molecule detection. The author lays out the process of isolating a single class-specific DNA aptamer that can bind to 12 diverse synthetic cathinones; the aptamer is insensitive to variations at all substituent sites on the core structure and it tolerates many substituents that do not appear in the research team’s selection targets. The research findings expand the capability of aptamers as class-specific biorecognition elements and demonstrate an unprecedented level of control over aptamer binding profiles through the new parallel-and-serial selection strategy which is presented in the dissertation. The author suggests that this approach can be used to isolate class-specific aptamers for other families of small molecules for applications relevant to medical diagnostics, environmental monitoring, food safety, and forensic science.