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PubMed · 16039606

Protease-activated quantum dot probes.

Emmanuel Chang·Jordan S Miller·Jiantang Sun·William W Yu·Vicki L Colvin·Rebekah Drezek·Jennifer L West
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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.

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Coated Materials, BiocompatibleFluorescent DyesGold ColloidLuminescent MeasurementsMaterials TestingPeptide HydrolasesPeptidesProtein Interaction MappingQuantum DotsSpectrometry, FluorescenceStaining and LabelingEvaluation StudyJournal ArticleResearch Support, U.S. Gov't, Non-P.H.S.

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Emmanuel Chang, Jordan S Miller, Jiantang Sun, William W Yu, Vicki L Colvin, Rebekah Drezek, Jennifer L West. 2005-09-09. Protease-activated quantum dot probes.. https://doi.org/10.1016/j.bbrc.2005.07.028

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