Thayer School of Engineering, Dartmouth College, 8000 Cummings Hall, Hanover, New Hampshire 03755, USA.
Opt Lett. 2011 Oct 1;36(19):3723-5. doi: 10.1364/OL.36.003723.
We used single-photon counting (SPC) detection for diffuse fluorescence tomography to image nanomolar (nM) concentrations of reporter dyes through a rat. Detailed phantom data are presented to show that every centimeter increase in tissue thickness leads to 1 order of magnitude decrease in the minimum fluorophore concentration detectable for a given detector sensitivity. Specifically, here, detection of Alexa Fluor 647 dyes is shown to be achievable for concentrations as low as 1 nM (<200 fM) through more than 5 cm in tissue phantoms, which indicates that this is feasible in larger rodent models. Because it is possible to detect sub-nM fluorescent inclusions with SPC technology in rats, it follows that it is possible to localize subpicomolar fluorophore concentrations in mice, putting the concentration sensitivity limits on the same order as nuclear medicine methods.
我们使用单光子计数 (SPC) 检测进行漫射荧光层析成像，通过大鼠来对纳摩尔 (nM) 浓度的报告染料进行成像。详细的体模数据表明，组织厚度每增加一厘米，对于给定的探测器灵敏度，可检测到的最小荧光团浓度就会降低一个数量级。具体来说，本文表明，通过组织体模中的超过 5 厘米，可实现对浓度低至 1 nM（<200 fM）的 Alexa Fluor 647 染料的检测，这表明在更大的啮齿动物模型中这是可行的。由于 SPC 技术在大鼠中有可能检测到亚纳摩尔的荧光内含物，因此可以在小鼠中定位亚皮摩尔浓度的荧光团，使浓度灵敏度与核医学方法处于同一水平。
