Aptamer-Based Fluorescent Biosensors

Abstract

Selected from random pools of DNA or RNA molecules through systematic evolution of ligands by exponential enrichment (SELEX), aptamers can bind to target molecules with high affinity and specificity, which makes them ideal recognition elements in the development of biosensors. To date, aptamer-based biosensors have used a wide variety of detection techniques, which are briefly summarized in this article. The focus of this review is on the development of aptamer-based fluorescent biosensors, with emphasis on their design as well as properties such as sensitivity and specificity. These biosensors can be broadly divided into two categories: those using fluorescently-labeled aptamers and others that employ label-free aptamers. Within each category, they can be further divided into “signal-on” and “signal-off” sensors. A number of these aptamer-based fluorescent biosensors have shown promising results in biological samples such as urine and serum, suggesting their potential applications in biomedical research and disease diagnostics.

In vitro transport activity of the fully assembled MexAB-OprM efflux pump from Pseudomonas aeruginosa

“…The RNA scaffold has a restriction site in which any nucleic acid material can be inserted 25 . Furthermore, DNA/RNA aptamers specific for an increasing number of targets are now available, and it has been shown that it is possible to rationally convert non-fluorescent aptamers into fluorescent reporters 26 . It has also been shown that fluorescent aptamers can be selected directly from random sequence DNA libraries in vitro 27 .…”

Aptamer-based fluorescence biosensor for chloramphenicol determination using upconversion nanoparticles

“…Owing to their high selectivity, stability, versatile target binding and easy regeneration capabilities over antibodies, aptamers have received considerable research attention as recognition probes in biodetections. Various aptamer-based biodetection schemes for biomolecules including fluorescence (Wang, Zhang, Cai, Cai, & Gao, 2011), electrochemistry (Chen, Yao, Xie, & Liu, 2014), surface plasma resonance (Tang, Su, & Loh, 2007), and chemiluminescence (Shim et al, 2014) have been demonstrated. Among these detection schemes, the fluorescencebased approach has attracted increasing interest due to its advantages in terms of simplicity, high sensitivity and good reproducibility.…”

Fluorescent Biosensors: Design and Application to Motor Proteins

“…They possess a typical stem-loop structure, which is disrupted by target association, resulting in the separation of the fluorophore-quencher pair [25]. A comprehensive description of the various types of aptamer sensors and their applications has been covered by several recent reviews [15,[26][27][28].…”