In vivo resolution of multiexponential decays of multiple near-infrared molecular probes by fluorescence lifetime-gated whole-body time-resolved diffuse optical imaging
In vivo resolution of multiexponential decays of multiple near-infrared molecular probes by fluorescence lifetime-gated whole-body time-resolved diffuse optical imaging
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DOI：
10.2310/7290.2007.00020
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发表时间：
2007-07-01
影响因子：
2.8
通讯作者：
Achilefu, Samuel
中科院分区：
文献类型：
--
作者：
Akers, Walter;Lesage, Frederic;Achilefu, Samuel
采用时间分辨漫射光学成像技术评估两种近红外荧光剂在体内的生物分布。细菌叶绿素a （BC）和cyp -glysine-arginine-天冬氨酸-丝氨酸-脯氨酸-赖氨酸- oh （Cyp-GRD）分别给药或联合给药于皮下移植人乳腺腺癌和缓释雌二醇微丸的小鼠，以改善肿瘤生长。在相同的激发波长（780 nm）和发射波长（830 nm）下，荧光分子探针在小鼠肿瘤模型中具有不同的荧光寿命分布。通过时间相关单光子计数对感兴趣的全身区域进行光栅扫描后重建荧光强度和寿命图。每个捕获的时间点扩展函数（TPSF）使用单指数和多指数衰变模型进行卷积，以最好地确定测量的荧光寿命。每个荧光团的相对信号被估计为扫描区域中任何感兴趣的区域。对来自全身荧光强度扫描的单个TPSFs进行反褶积，提供相应的寿命图像，用于比较单个成分的生物分布。体内荧光寿命分别为0.8 ns （Cyp-GRD）和2 ns （13C）。本研究表明，使用时域荧光寿命门控方法可以划分具有相似光谱特征的单个荧光团的相对生物分布。
The biodistribution of two near-infrared fluorescent agents was assessed in vivo by time-resolved diffuse optical imaging. Bacteriochlorophyll a (BC) and cypate-glysine-arginine-aspartic acid-serine-proline-lysine-OH (Cyp-GRD) were administered separately or combined to mice with subcutaneous xenografts of human breast adenocarcinoma and slow-release estradiol pellets for improved tumor growth. The same excitation (780 nm) and emission (830 nm) wavelengths were used to image the distinct fluorescence lifetime distribution of the fluorescent molecular probes in the mouse cancer model. Fluorescence intensity and lifetime maps were reconstructed after raster-scanning whole-body regions of interest by time-correlated single-photon counting. Each captured temporal point-spread function (TPSF) was cleconvolved using both a single and a multiexponental decay model to best determine the measured fluorescence lifetimes. The relative signal from each fluorophore was estimated for any region of interest included in the scanned area. Deconvolution of the individual TPSFs from whole-body fluorescence intensity scans provided corresponding lifetime images for comparing individual component biodistribution. In vivo fluorescence lifetimes were determined to be 0.8 ns (Cyp-GRD) and 2 ns (13C). This study demonstrates that the relative biodistribution of individual fluorophores with similar spectral characteristics can be compartmentalized by using the time-domain fluorescence lifetime gating method.