Predictions of novel two-photon absorption bands in fluorescent proteins.
By means of time-dependent density functional theory, we calculate the two-photon cross-sections for the lowest relevant excitations in some model chromophores of intrinsically fluorescent proteins. The two-photon strength of the first, one-photon active transition varies among the various chromophores, in line with experimental findings. Interestingly, additional transitions with large two-photon cross-sections are found in the 500-700 nm region arising from near-resonant enhancement, as revealed by few-state model analysis. Multiphoton excitation of fluorescent proteins in this spectral region can lead to relevant application for bioimaging.
Nifosì
Riccardo
R
NEST-CNR INFM, Scuola Normale Superiore, Piazza dei Cavalieri 7, Pisa I-56126, Italy. r.nifosi@sns.it
Luo
Yi
Y
D000838:Anions / Q000737:chemistry; D008164:Luminescent Proteins / Q000737:chemistry*; D008958:Models, Molecular; D015394:Molecular Structure; D017785:Photons; D013053:Spectrophotometry; D013499:Surface Properties
D000838:Anions; D008164:Luminescent Proteins