Photon Cross Correlation Spectroscopy

Project Information

PHOCCS

Grant agreement ID: 664738

DOI

10.3030/664738

Project closed

EC signature date 12 March 2015

Start date 1 May 2015

End date 31 October 2016

Funded under

• EXCELLENT SCIENCE - European Research Council (ERC)

Total cost

€ 149 984,00

EU contribution

€ 149 984,00

Coordinated by

CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE CNRS
France

Periodic Reporting for period 1 - PHOCCS (Photon Cross Correlation Spectroscopy)

Reporting period: 2015-05-01 to 2016-10-31

Summary of the context and overall objectives of the project

Efficiently detecting DNA sequences within a limited time is vital for disease screening and public health monitoring. This calls for a new method that combines high sensitivity, fast read-out time and easy manipulation of the sample, avoiding the extensive steps of DNA amplification, purification or grafting to a surface. Here, we introduce dual-color photon cross correlation spectroscopy as a new method for specific DNA sensing with high sensitivity in a single step homogeneous solution phase. Our approach is based on confocal dual-color illumination and detection of the scattering intensities from individual silver nanoparticles and gold nanorods. In the absence of the target DNA, the nanoparticles move independently and their respective scattering signals are uncorrelated. In the presence of the target DNA, the probe-functionalized gold and silver nanoparticles assemble via DNA hybridization with the target, giving rise to temporal coincidences between the signals scattered by each nanoparticle. The degree of coincidence accurately quantifies the amount of target DNA. To demonstrate the efficiency of our technique, we detect a specific DNA sequence of sesame, an allergenic food ingredient, for a range of concentration from 5 pM to 1.5 nM with a limit of detection of 1 pM. Our method is sensitive and specific enough to detect single nucleotide deletion and mismatch. With the dual-color scattering signals being much brighter than fluorescence-based analogs, the analysis is fast, quantitative, and simple to operate, making it valuable for biosensing applications.