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Fluorescence lifetime biosensing with DNA microarrays and a CMOS-SPAD imager

Research output: Contribution to journalArticle

Original languageEnglish
Pages (from-to)1302-1308
Number of pages7
JournalBiomedical Optics Express
Volume1
Issue number5
DOIs
StatePublished - 1 Dec 2010

Abstract

Fluorescence lifetime of dye molecules is a sensitive reporter on local microenvironment which is generally independent of fluorophores concentration and can be used as a means of discrimination between molecules with spectrally overlapping emission. It is therefore a potentially powerful multiplexed detection modality in biosensing but requires extremely low light level operation typical of biological analyte concentrations, long data acquisition periods and on-chip processing capability to realize these advantages. We report here fluorescence lifetime data obtained using a CMOS-SPAD imager in conjunction with DNA microarrays and TIRF excitation geometry. This enables acquisition of single photon arrival time histograms for a 320 pixel FLIM map within less than 26 seconds exposure time. From this, we resolve distinct lifetime signatures corresponding to dye-labelled HCV and quantum-dot-labelled HCMV nucleic acid targets at concentrations as low as 10 nM.

ID: 4666178