ABSTRACT
It is well known that 1O2 is the main mediator of the photodynamic therapy (PDT) effect.1 For this, numerous eorts have been made to detect 1O2 in vitro as well as in vivo. e detection methods of
4.1 Introduction 67
4.1.1 Singlet oxygen detection methods 68
4.1.1.1Direct singlet oxygen luminescence detection and imaging 68
4.1.1.2 Steady-state imaging 69
4.1.1.3 Time-resolved imaging 70
4.2Discussion of singlet oxygen luminescence imaging in specific systems 70
4.2.1 Evaluation of NIR luminescence kinetics in model systems 71
4.2.2 Skin 73
4.2.2.1 Time-resolved singlet oxygen luminescence and the structure of skin 74
4.2.2.2 Time-resolved singlet oxygen luminescence and the microarchitecture of the skin76
4.2.3 Blood vessels 78
4.2.3.1Dorsal skinfold window chamber model 78
4.2.3.21O2 Luminescence image of blood vessel 79
4.2.3.3 Chicken chorioallantoic membrane model 81
4.2.4 Solid tumor models 81
4.3 Conclusions and outlook 83
Acknowledgments 84
References 84
1O2 range from indirect methods using monitor molecules, other indirect methods that do not require additional drugs, to direct 1O2 detection via its weak near-infrared (NIR) phosphorescence at around 1270 nm.2-9
e registration of this NIR phosphorescence is believed to be a potent PDT dosimetry technique that may be used for improving the treatment eciency. Furthermore, it can be used for quantitative investigations of the mechanism of 1O2 generation and its interaction with the microenvironment of the PS.10,11
Elevating the ability of 1O2 NIR detection to an imaging level will greatly improve knowledge about basic processes. e advantages, problems, and prospects of state-of-the art imaging methods will be discussed in this chapter.
