Sol-gel SELEX circumventing chemical conjugation of low molecular weight metabolites discovers aptamers selective to xanthine.

TitleSol-gel SELEX circumventing chemical conjugation of low molecular weight metabolites discovers aptamers selective to xanthine.
Publication TypeJournal Article
Year of Publication2013
AuthorsBae H, Ren S, Kang J, Kim M, Jiang Y, Jin MM, Min IM, Kim S
JournalNucleic Acid Ther
Volume23
Issue6
Pagination443-9
Date Published2013 Dec
ISSN2159-3345
KeywordsAptamers, Nucleotide, High-Throughput Nucleotide Sequencing, Molecular Weight, Phase Transition, Purines, SELEX Aptamer Technique, Sequence Analysis, DNA, Xanthine
Abstract

Sensitive detection of the metabolites indicative of a particular disease contributes to improved therapy outcomes. Developing binding reagents for detection of low molecular weight metabolites is hampered by the difficulty with immobilization of targets through appropriate covalent chemical linkage while ensuring that selected reagents retain specificity to unmodified metabolites. To circumvent chemical modification of targets, we employed sol-gel droplets deposited onto a porous silicon chip to entrap a purine metabolite, xanthine, which was found at lower levels in urine samples from patients with non-Hodgkin lymphoma. By sol-gel SELEX (systematic evolution of ligands by exponential enrichment) against xanthine, specific aptamers (KD ∼ 10 μM) with sensitivity of detection at as low as 1 μM were isolated, which bound to other purine metabolites at more than 100-fold lower affinity. In contrast, we failed to isolate xanthine-specific aptamers when SELEX was performed against xanthine covalently linked to polymer resin. This study demonstrates that the sol-gel platform for entrapping low molecular weight metabolites without chemical modifications can be utilized for SELEX to discover aptamers against clinical metabolite markers for diagnosis application.

DOI10.1089/nat.2013.0437
Alternate JournalNucleic Acid Ther
PubMed ID24256293
Related Institute: 
Molecular Imaging Innovations Institute (MI3)

Weill Cornell Medicine
Department of Radiology
525 East 68th Street New York, NY 10065