Pump Probe & Flash Photolysis

Pump-Probe & flash photolysis are extensions of absorption spectroscopy. The absorbance at a particular wavelength or range of wavelengths of a sample is measured as a function of time after excitation by a flash of light. In a typical experiment, the light excitation is generated by a pulsed laser or LED.  Absorbance, fluorescence and circular dichroism are useful tools for monitoring kinetic changes of chemical and biological systems.  Flash photolysis measurements are initiated with an intense short light pump pulse from a laser, flash lamp, or LED.   The excited electronic state caused by the pump pulse induces a physical or chemical change observed by absorbance or fluorescence.  OLIS systems target changes in the microsecond to second range.

Examples of processes that can be studied:

Protein conformational changes induced by light

Photosynthesis of algae or photosynthetic bacteria

Rapid chemical kinetics using caged compounds

Models which support Pump-Probe & Flash Photolysis


DB 620 UV/Vis [NIR] Spectrophotometer

DB 620 UV/Vis [NIR] Spectrophotometer

Olis RSM 1000 UV/Vis[NIR] Rapid-scanning Spectrophotometer

Olis RSM 1000 UV/Vis[NIR] rapid-scanning spectrophotometer


Today, flash photolysis and pump-probe are extensively used by researchers to study:

  • light-induced processes in organic molecules
  • polymers
  • nanoparticles
  • semiconductors
  • photosynthesis in plants
  • signaling
  • light induced conformation changes in biological systems
Client Publications
AL Odom, AF Heyduk, DG Nocera Photochemistry of dirhodium(II,II) diphosphazane tetrachloride complexes 2000 InorganicaChimicaActa 297, 330-337 Cary 17
MZ Cabail, PJ Lace, J Uselding, AA Pacheco Kinetic studies of the photoinitiated NO-releasing reactions of N,N′-bis-(carboxymethyl)-N,N′-dinitroso-1,4-phenylenediamine 2002 J Photochemistry and Photobiology: Chemistry 152, 109-121 RSM 1000
MZ Cabail, V Mona, E Bae, A Meyor, AA Pacheco Quantifying the Photoinduced Release of Nitric Oxide from N,N‘-Bis(carboxymethyl)-N,N‘-dinitroso-1,4-phenylenediamine. Effect of Reducing Agents on the Mechanism of the Photoinduced Reactions 2007 J Phys. Chem. A. 111, 1207-1213 RSM 1000
A Ali, M Forbes, A Woolley Optimizing photo-control of bZIP coiled-coils by azobenzene cross-linkers: Role of the cross-linking site. 2015 ChemBioChem DOI: 10.1002/cbic.201500191 RSM 1000
JP Zayner and TR Sosnick Factors That Control the Chemistry of the LOV Domain Photocycle 2014 PLoS ONE 9(1): e87074 HPDA 8452
DK Yadav, A Prasad, J Kruk, P Pospisil Evidence for the Involvement of Loosely Bound Plastosemiquinones in Superoxide Anion Radical Production in Photosystem II 2014 PLoS ONE 9(12): e115466 RSM 1000