TY - JOUR
T1 - Azadioxatriangulenium and diazaoxatriangulenium
T2 - quantum yields and fundamental photophysical properties
AU - Bogh, Sidsel Ammitzbøll
AU - Simmermacher, Mats
AU - Westberg, Michael
AU - Bregnhøj, Mikkel
AU - Rosenberg, Martin
AU - De Vico, Luca
AU - Veiga, Manoel
AU - Laursen, Bo Wegge
AU - R. Ogilby, Peter
AU - Sauer, Stephan P. A.
AU - Sørensen, Thomas Just
PY - 2017/1/31
Y1 - 2017/1/31
N2 - Over the last decade, we have investigated and exploited the photophysical properties of triangulenium dyes. Azadioxatriangulenium (ADOTA) and diazaoxatriangulenium (DAOTA), in particular, have features that make them useful in various fluorescence-based technologies (e.g., bioimaging). Through our work with ADOTA and DAOTA, we became aware that the reported fluorescence quantum yields (ϕfl) for these dyes are lower than their actual values. We thus set out to further investigate the fundamental structure–property relationships in these unique conjugated cationic systems. The nonradiative processes in the systems were explored using transient absorption spectroscopy and time-resolved emission spectroscopy in combination with computational chemistry. The influence of molecular oxygen on the fluorescence properties was explored, and the singlet oxygen sensitization efficiencies of ADOTA and DAOTA were determined. We conclude that, for these dyes, the amount of nonradiative deactivation of the first excited singlet state (S1) of the azaoxa-triangulenium fluorophores is low, that the rate of such deactivation is slower than what is observed in common cationic dyes, that there are no observable radiative transitions occurring from the first excited triplet state (T1) of these dyes, and that the efficiency of sensitized singlet oxygen production is low (ϕΔ ≤ 10%). These photophysical results provide a solid base upon which technological applications of these fluorescent dyes can be built.
AB - Over the last decade, we have investigated and exploited the photophysical properties of triangulenium dyes. Azadioxatriangulenium (ADOTA) and diazaoxatriangulenium (DAOTA), in particular, have features that make them useful in various fluorescence-based technologies (e.g., bioimaging). Through our work with ADOTA and DAOTA, we became aware that the reported fluorescence quantum yields (ϕfl) for these dyes are lower than their actual values. We thus set out to further investigate the fundamental structure–property relationships in these unique conjugated cationic systems. The nonradiative processes in the systems were explored using transient absorption spectroscopy and time-resolved emission spectroscopy in combination with computational chemistry. The influence of molecular oxygen on the fluorescence properties was explored, and the singlet oxygen sensitization efficiencies of ADOTA and DAOTA were determined. We conclude that, for these dyes, the amount of nonradiative deactivation of the first excited singlet state (S1) of the azaoxa-triangulenium fluorophores is low, that the rate of such deactivation is slower than what is observed in common cationic dyes, that there are no observable radiative transitions occurring from the first excited triplet state (T1) of these dyes, and that the efficiency of sensitized singlet oxygen production is low (ϕΔ ≤ 10%). These photophysical results provide a solid base upon which technological applications of these fluorescent dyes can be built.
KW - Faculty of Science
U2 - 10.1021/acsomega.6b00211
DO - 10.1021/acsomega.6b00211
M3 - Journal article
SN - 2470-1343
VL - 2
SP - 193
EP - 203
JO - ACS Omega
JF - ACS Omega
IS - 1
ER -