title: Aptamer-based folding fluorescent sensor for cocaine.
abstract: We adapted in two steps a deoxyribonucleotide-based aptamer to signal the recognition of cocaine: an instability was engineered in one stem of a three-way junction that forms the cocaine-binding pocket and the resulting short stem was end labeled with a fluorophore and a quencher. In the absence of cocaine, two stems are open, but in its presence they close and the three-way junction forms. This major structural change brings fluorophore and quencher together thereby signaling the presence and concentration of ligand. The sensor is selective for cocaine over its metabolites, can operate in serum, and is useful for the screening of cocaine hydrolases.
authors.affiliation: Division of Clinical Pharmacology and Experimental Therapeutics, Department of Medicine, Columbia University, 630 West and 168th Street, New York, New York 10032, USA.
authors.forename: M N
authors.initials: MN
authors.lastname: Stojanovic
authors.forename: P
authors.initials: P
authors.lastname: de Prada
authors.forename: D W
authors.initials: DW
authors.lastname: Landry
mesh_terms: D003042:Cocaine / Q000032:analysis*; D003854:Deoxyribonucleotides / Q000737:chemistry*; D005456:Fluorescent Dyes / Q000737:chemistry*
chemical_list: D003854:Deoxyribonucleotides; D005456:Fluorescent Dyes; D003042:Cocaine