In Vitro Selection of RNA Aptamers to a Small Molecule Target

Abstract

This unit describes the selection of aptamers from a single-stranded RNA pool that bind to small molecule targets. Aptamers generated by this type of selection experiment can potentially function as receptors for small molecules in numerous applications, including medical diagnostics, therapeutics, and environmental monitoring. This unit describes two modes of selection, one by column filtration and one by batch selection.

From SELEX to Cell

“…There are several detailed reviews available which provide a more in-depth coverage of SELEX, and the reader is encouraged to use them (Codrea et al, 2010;Conrad et al, 1995;Klug and Famulok, 1994). There are several detailed reviews available which provide a more in-depth coverage of SELEX, and the reader is encouraged to use them (Codrea et al, 2010;Conrad et al, 1995;Klug and Famulok, 1994).…”

Aptamer-Functionalized Nanoparticles for Drug Delivery

“…70 Compared with their synthetic counterpart, i.e., antibodies, aptamers possess a number of superior attributes. (a) selection against a wide range of target molecules, such as metal ions, toxins, enzymes, proteins, organic dyes, nucleotides, amino acids, viruses, bacteria, or even whole cells; [71][72][73][74][75][76][77][78][79][80][81][82] (b) easy synthesis via phosphoramidite chemistry; (c) easy modification with electrochemical probes, fluorophores and quenchers; 83 (d) high stability, even at elevated temperatures, pH, and organic solvents, indicating that aptamers could be used in a wide range of assay conditions; [84][85][86] (e) ability to interact with other DNA or RNA molecules, such as DNAzymes, and ability to hybridize with their complementary sequences, markedly broadening applications of the corresponding biosensors, with the added functionality of incorporation into one-, two-or even three-dimensional DNA-based nanostructures, 87-92 meaning that they have strong potential to be used for clinical and diagnostic applications; [93][94][95] (f) construction of aptamer-based biosensors facilitated by their conformational variations, including G-quadruplex and hairpin structures; (g) less nonspecific adsorption on aptamer surfaces. 96 However, before some applications are put into clinical practice, some issues remain to be resolved.…”

Analytical potential of gold nanoparticles in functional aptamer-based biosensors

“…Aptamer binding affinity constants can be validated to confirm its specificity and affinity for the target by using techniques such as isocratic elution, equilibrium gel filtration, microdialysis, ultrafiltration, fluorescence, and surface plasmon resonance spectroscopy [29][30][31][32][33][34][35]. For example, the most commonly used aptamers for human α-thrombin were screened out by two groups using SELEX process, respectively [36,37].…”