title: Straightforward FRAP for quantitative diffusion measurements with a laser scanning microscope.
abstract: Confocal or multi-photon laser scanning microscopes are convenient tools to perform FRAP diffusion measurements. Despite its popularity, accurate FRAP remains often challenging since current methods are either limited to relatively large bleach regions or can be complicated for non-specialists. In order to bring reliable quantitative FRAP measurements to the broad community of laser scanning microscopy users, here we have revised FRAP theory and present a new pixel based FRAP method relying on the photo bleaching of rectangular regions of any size and aspect ratio. The method allows for fast and straightforward quantitative diffusion measurements due to a closed-form expression for the recovery process utilizing all available spatial and temporal data. After a detailed validation, its versatility is demonstrated by diffusion studies in heterogeneous biopolymer mixtures.
authors.affiliation: Biophotonic Imaging Group, Lab General Biochemistry and Physical Pharmacy, Ghent University, Harelbekestraat 72, B-9000 Gent, Belgium.
authors.forename: Hendrik
authors.initials: H
authors.lastname: Deschout
authors.forename: Joel
authors.initials: J
authors.lastname: Hagman
authors.forename: Sophia
authors.initials: S
authors.lastname: Fransson
authors.forename: Jenny
authors.initials: J
authors.lastname: Jonasson
authors.forename: Mats
authors.initials: M
authors.lastname: Rudemo
authors.forename: Niklas
authors.initials: N
authors.lastname: Lorén
authors.forename: Kevin
authors.initials: K
authors.lastname: Braeckmans