Protein Quantification Using Resonance Energy Transfer between Donor Nanoparticles and Acceptor Quantum Dots

Citations Over TimeTop 15% of 2013 papers

Abstract

A homogeneous time-resolved luminescence resonance energy transfer (TR-LRET) assay has been developed to quantify proteins. The competitive assay is based on resonance energy transfer (RET) between two luminescent nanosized particles. Polystyrene nanoparticles loaded with Eu(3+) chelates (EuNPs) act as donors, while protein-coated quantum dots (QDs), either CdSe/ZnS emitting at 655 nm (QD655-strep) or CdSeTe/ZnS with emission wavelength at 705 nm (QD705-strep), are acceptors. In the absence of analyte protein, in our case bovine serum albumin (BSA), the protein-coated QDs bind nonspecifically to the EuNPs, leading to RET. In the presence of analyte proteins, the binding of the QDs to the EuNPs is prevented and the RET signal decreases. RET from the EuNPs to the QDs was confirmed and characterized with steady-state and time-resolved luminescence spectroscopy. In accordance with the Förster theory, the approximate average donor-acceptor distance is around 15 nm at RET efficiencies, equal to 15% for QD655 and 13% for QD705 acceptor, respectively. The limits of detection are below 10 ng of BSA with less than a 10% average coefficient of variation. The assay sensitivity is improved, when compared to the most sensitive commercial methods. The presented mix-and-measure method has potential to be implemented into routine protein quantification in biological laboratories.

Related Papers

• → [13] Fluorescence resonance energy transfer(1995)516 cited
• → Fluorescence Resonance Energy Transfer-Based Stoichiometry in Living Cells(2002)357 cited
• → Global analysis of Förster resonance energy transfer in live cells measured by fluorescence lifetime imaging microscopy exploiting the rise time of acceptor fluorescence(2010)84 cited
• → Förster resonant energy transfer in quantum dot layers(2009)26 cited
• → Effect of plasmonic nanostructures and nanofilms on fluorescence resonance energy transfer(2009)29 cited