Design and synthesis of novel chromophores for aptamer based imaging

Abstract

Fluorescent proteins are an incredibly versatile tool in biological imaging. Unfortunately, fluorescent proteins cannot be used to track small metabolites in vivo. The purpose of the work described herein was to create novel red-shifted RNA aptamer based probes for use in molecular imaging. All potential dyes were prescreened using molecular modeling and only the dyes that absorbed wavelengths longer than 500 nm were synthesized. The first aminothiophene based imidazolinone dyes (ATI-1 and ATI-2) were synthesized and their electronic properties were evaluated. SELEX was performed on ATI-2 to find several random RNA sequences that were capable of binding the chromophore and activating ATI-2 fluorescence. It is proposed that fluorescence activated cell sorting can be used to separate and isolate the sequences that form the brightest complexes with ATI-2.