title: Protease-activated quantum dot probes.
abstract: We have developed a novel nanoparticulate luminescent probe with inherent signal amplification upon interaction with a targeted proteolytic enzyme. This construct may be useful for imaging in cancer detection and diagnosis. In this system, quantum dots (QDs) are bound to gold nanoparticles (AuNPs) via a proteolytically degradable peptide sequence to non-radiatively suppress luminescence. A 71% reduction in luminescence was achieved with conjugation of AuNPs to QDs. Release of AuNPs by peptide cleavage restores radiative QD photoluminescence. Initial studies observed a 52% rise in luminescence over 47 h of exposure to 0.2 mg/mL collagenase. These probes can be customized for targeted degradation simply by changing the sequence of the peptide linker.
authors.affiliation: Rice University, Department of Bioengineering MS-142, P.O. Box 1892, Houston, TX 77251-1892, USA.
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Chang
authors.forename: Jordan S
authors.initials: JS
authors.lastname: Miller
authors.forename: Jiantang
authors.initials: J
authors.lastname: Sun
authors.forename: William W
authors.initials: WW
authors.lastname: Yu
authors.forename: Vicki L
authors.initials: VL
authors.lastname: Colvin
authors.forename: Rebekah
authors.initials: R
authors.lastname: Drezek
authors.forename: Jennifer L
authors.initials: JL
authors.lastname: West
mesh_terms: D020099:Coated Materials, Biocompatible / Q000032:analysis / Q000737:chemistry*; D005456:Fluorescent Dyes / Q000032:analysis / Q000737:chemistry*; D017979:Gold Colloid / Q000737:chemistry*; D008163:Luminescent Measurements / Q000379:methods*; D008422:Materials Testing; D010447:Peptide Hydrolases / Q000032:analysis* / Q000737:chemistry*; D010455:Peptides / Q000737:chemistry; D025941:Protein Interaction Mapping / Q000379:methods; D045663:Quantum Dots; D013050:Spectrometry, Fluorescence / Q000379:methods; D013194:Staining and Labeling / Q000379:methods
chemical_list: D020099:Coated Materials, Biocompatible; D005456:Fluorescent Dyes; D017979:Gold Colloid; D010455:Peptides; D010447:Peptide Hydrolases