构建由脂肪乳剂和墨水组成的皮肤组织模型, 定量研究皮肤组织模型的吸收系数μa和散射系数μs对光敏化单线态氧(singlet oxygen, 1O2)发光特性的影响。利用1O2发光检测系统测量含光敏剂四硫磺基酞菁氯化铝的皮肤组织模型分别在中心波长为1 230, 1 270和1 310 nm处的时间分辨发光光谱, 对扣除背景信号后的时间分辨1O2发光光谱进行积分和拟合, 获得1O2发光积分强度以及激发三重态寿命τT和1O2寿命τD。结果表明在皮肤组织模型中, 1O2发光积分强度随着μa和μs的增大而减小, μa对τT和τD没有影响。τT随着μs的增加而增加, τD随μs的增加先骤降而后缓慢上升。当μa>1.5 mm-1和μs>32 cm-1时, 1O2发光积分强度和τT、τD均趋于稳定, 其中τT和τD分别为3.4±0.6 μs和3.3±0.7 μs。

The effects of absorption coefficient and scattering coefficient on singlet oxygen (1O2) luminescence in skin phantoms were quantitatively studied.In this study, Aluminum phthalocyanine disulfonic acid (AlPcS) was utilized as the model photosensitizer, and India ink and 10% Intralipid were chosen as the absorber and scatter for skin phantom, respectively. A custom-built time and spectral-resolved near-infrared (NIR) detection system was used for 1O2 luminescence measurements. Three bandpass-filters centered at 1 230, 1 270 and 1 310 nm were selected to discriminate the1O2 luminescence from background luminescence signal. The integrated intensity of 1O2 luminescence, lifetime of triplet excited-state and 1O2 were then derived from the 1O2 luminescencespectra after background subtraction. The results indicated that the integrated intensity of 1O2 luminescenceis decreased with the increase of μa and μs, and μa alone has no significant influence of on τT and τD is decreased with the increase of μs, while τD is dramatically decreased and then increased slowly.However, the integrated intensity of 1O2 luminescence, as well as τT and τD are quiet stable once μa>1.5 mm-1 and μs>32 cm-1.τT and τD of AlPcS in skin phantoms are 3.4±0.6 μs and 3.3±0.7 μs, respectively.