皮肤组织模型中吸收和散射系数对单线态氧发光特性的影响

摘要

The effects of absorption coefficient and scattering coefficient on singlet oxygen (1 O2 )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 1 O2 lumines-cence measurements.Three bandpass-filters centered at 1 230,1 270 and 1 310 nm were selected to discriminate the 1 O2 luminescence from background luminescence signal.The integrated intensity of 1 O2 luminescence,lifetime of triplet excited-state and 1 O2 were then derived from the 1 O2 luminescencespectra after background subtraction.The results indi-cated that the integrated intensity of 1 O2 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 in-creased slowly.However,the integrated intensity of 1 O2 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.%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，1 O2）发光特性的影响。利用1 O2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1230，1270和1310 nm 处的时间分辨发光光谱，对扣除背景信号后的时间分辨1 O2发光光谱进行积分和拟合，获得1 O2发光积分强度以及激发三重态寿命τT 和1 O2寿命τD。结果表明在皮肤组织模型中，1 O2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，1 O2发光积分强度和τT、τD 均趋于稳定，其中τT 和τD 分别为3．4±0．6μs 和3．3±0．7μs。