Aptamer sandwich-based carbon nanotube sensors for single-carbon-atomic-resolution detection ofnon-polar small molecular species

Abstract

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.

Development of Single-Stranded DNA Aptamers for Specific Bisphenol A Detection

“…Using these sensors, we demonstrated the detection limit of 1 pM and single-carbon-atomic resolution (Lee et al, 2011). These results demonstrate that specific aptamers of small molecules can be used in many sensor applications, such as environmental monitorization and food safety.…”

Advances in Aptamer-Based Biosensors for Food Safety

“…As seen in Table 1, several aptamers and aptamer platforms have been developed in response to these concerns. For example, Lee et al developed an aptamer-sandwich based carbon nanotube sensor able to detect BPA at very low concentrations (Lee et al, 2011).…”

Systematic Selection of Modified Aptamer Pairs for Diagnostic Sandwich Assays

“…This feature, combined with the added specificity inherent in two-reagent sandwich-type measurements, may facilitate the development of sandwich assays with greater specificity and potential for higher multiplexing abilities compared with what can be achieved with antibodies. SOMAmer pairs hold promise for the development of specific panels in various areas of medical diagnostics for which a large installed base of instruments is already in place, using traditional sandwich assays or novel ligand proximity assays (19,20), and also for small molecular sensing platforms (21,22). …”