High contrast imaging of reversibly switchable fluorescent proteins via   temporally unmixed Multispectral Optoacoustic Tomography (tuMSOT)
  Photocontrol of reversibly switchable fluorescent proteins (RSFPs) was used to program optoacoustic signal time courses that were temporally unmixed to increase the proteins contrast-to-noise-ratios (CNRs) in optoacoustic imaging. In this way, two variants of the RSFP Dronpa with very similar optoacoustic spectra could be readily discriminated in the presence of highly absorbing blood. Addition of temporal unmixing to multispectral optoacoustic tomography (tuMSOT) in conjunction with synthetic or genetically controlled photochromic contrast agents and customized photoswitching schedules can increase the performance of multiplexed and high contrast molecular optoacoustic imaging. 
Andre C Stiel, X Luis Dean-Ben, Yuanyuan Jiang, Vasilis Ntziachristos,   Daniel Razansky and Gil G Westmeyer
physics.optics