Exponential enrichment

Tuerk, C. Gold, L. Systematic evolution of ligands by exponential enrichment RNA ligands to bacteriophage T4 DNA polymerase. Science 1990, 249, 505-510. 

Although its use in ligand selection for large scale of affinity chromatography is not wide, ribosome display and systematic evolution of ligands by exponential enrichment (SELEX) may... 

SELEX (systematic evolution of ligands by exponential enrichment) is used to generate aptamers, oligonucleotides selected to tightly bind a specific molecular target. The process is generally automated to allow rapid identification of one or more aptamers with the desired binding specificity. 

Aptamers are nucleic acids which exhibit a defined structure due to their nucleotide sequence and therefore, are able to specifically bind selected targets [1] (aptus [lat.] = fitting, sticking to). Aptamers and likewise, ribozymes [2] and deoxyribozymes [3] are selected in vitro by screening nucleic acid libraries. Here we describe in detail the selection of aptamers by a process called SELEX (Systematic Evolution of Ligands by Exponential enrichment) [4]. 

Fig. 2.5 (a) An aptamer-target protein interaction (adapted from Tuerk and Gold 1990, p. 505). (b) Principle of the Systematic Evolution of Ligands by Exponential Enrichment (SELEX) process (adapted from Tombelli et al., 2005, p. 2424)... 

D Irvine, C Tuerk, L Gold. SELEXION. Systematic evolution of ligands by exponential enrichment with integrated optimization by non-linear analysis. J Mol Biol 222 739-761, 1991. 

B.23 SELEX Systematic Evolution of Ligands by Exponential Enrichment 433... 

---